Fall Garden Prep for the Native Plant Garden 

The leaves are starting to turn colour, the air is getting cooler, and there are lots of gardening articles being written about what to do with your Canna Lilies and rose bushes and dahlias for the winter. But what about those of us who grow native plants? Do we have to do anything to prepare our plants and flower beds for winter? After all, Mother Nature has been looking after herself for millennia. 

How much fall prep you do will depend primarily on WHY you grow native plants.  

Leave the Plant Stalks 

When I started growing natives, I came from a background of conventional gardening, and the easiest way to put my native plant gardens to bed for the winter was to simply set my mulching mower as high as it would go and mow everything down. The result was a tidy looking flower bed that was ready to emerge in the spring.  

In the spring, after an extensive fall clean up, the flowerbeds looked tidy, but there was no shelter for overwintering insects.

Unfortunately, I also removed important habitat for bees and other insects. 

As my understanding grew of the importance of leaving stems for leaf cutter and wool carder bees and for small carpenter bees and others, I had to change my mind set. I started to leave a few of the pithy stems of Monarda (Bee Balm and Wild Bergamot) but I still “cleaned up” the rest of the flower beds by cutting down the asters, Joe Pye weed, coneflowers, etc. and hauling the debris to the municipal yard for composting.  

Leaving those stems was really hard to do – at first. It offended my sensibilities as to what a neat and tidy garden should look like for the winter. But whether it was my imagination or reality, I thought I detected more bees the next year, and more species of bees as well. So when fall rolled around again I compromised – I cut down most of the plants to about 18”, and rather than hauling the debris away, I cut it into 1-2’ lengths and left it on the ground.

Because my gardens are very densely planted, and some with very tall plants, I would have had a foot of cuttings if I dropped them all in the garden, so I kept it to a minimum by leaving one thin layer in the flowerbed, and placing the remaining stems in an out of the way corner of the yard. 

Surprisingly, it was my mindset that had the greatest change as a result of this new strategy. I no longer saw a “mess” in the flowerbed in the fall. Instead, I saw potential habitat. I saw that I was giving Mother Nature a helping hand. It’s one thing to provide native plants for bees, butterflies and caterpillars to feed on during the summer, but if you don’t provide them with a place to overwinter, then you are really only helping those species that migrate. 

Leaving the flower stalks has, in addition to the wildlife benefit, the added beauty of great structure in the winter garden. 

But is leaving the stems the only thing we can do?  

Leave the Leaves 

Leaving the leaves on our lawns is just about as difficult to do as leaving plant stems in the gardens for the winter for most of us. But it is just as important. I do rake my lawn in the fall, but I have much less area of lawn than I do of flowerbeds, so the leaves get raked onto the beds. They provide mulch to keep annual weeds down in the spring, and fertilizer as the leaves decay. And depending on the bed, I may put just a thin layer (on the beds of prairie species, for example) or a layer at least 6” thick under the sugar maples where Trilliums, Jack in the Pulpit, and other spring ephemerals need the organic matter and moisture retaining quality of the decaying leaves.  

Most of our spring forest wildflowers require deep, humus-rich soils to flourish. Decaying leaves provide this.

I actually have so many trees in my yard now that I now create piles of the excess leaves in the fall to be spread over the shade garden in mid-May when most of the leaves there have been consumed by insects, worms and microbes.  

But why is it important to leave the leaves, other than for mulch and natural fertilizer? 

For starters, many of our butterflies and some of our more spectacular moths overwinter in the leafy debris. 

According to the Royal Ontario Museum’s book Butterflies of Ontario, of the 127 species of butterflies in this province, 110 overwinter here.  

  • 6 overwinter as adults 
  • 12 overwinter as eggs 
  • 30 overwinter as a chrysalis 
  • 60 overwinter as a caterpillar, and  
  • 2 overwinter as either a caterpillar or a chrysalis. 

Many of these hide either in the leaf litter or in the ground (where the leaf litter helps to keep them warm). 

Many of our moths do the same. The ones we tend to get excited about – the large, showy ones – are no different. For instance, the beautiful green Luna Moth overwinters by using its silk to bind dead leaves around its cocoon. The Virgin Tiger Moth overwinters as a caterpillar, hiding in the leaf litter. And as for everyone’s favourite – the Hummingbird Clearwing Moth – the fully-grown caterpillars burrow in the leaf litter to pupate, emerging soon after and overwintering as an adult, or waiting in the cocoon until the following spring to emerge.  

So the less we can disturb the leaf litter, the better, as far as I am concerned.  

Do it for the Bees, Too 

We also have a number of ground nesting bees that greatly benefit from a quilt of leaves to help maintain a comfortable temperature all winter long. The leaves have the added benefit of slowing down the heating of the soil in a January thaw that might cause the bees to emerge too early before any food sources are available. 

The American Sand Wasp (Bembix americana) is just one of many ground nesting bees and wasps. These wasps are solitary predators that primarily target flies – including the annoying horse and deer flies – for their developing larvae. When the larvae mature, the tunnel is sealed for the winter. They pupate in spring and come out from their tunnels in summer.

As you start thinking about preparing your garden for its long winter rest, think of the insects that need the stems and leaves to survive till spring. Leave some stems, and leave the leaves. 

Got Shade? Part 2 – Summer in the Shade 

This spring, I wrote an article about spring ephemerals – those woodland species that flower early in the spring and then, for the most part, disappear till the following year. Summer has arrived and we have a number of shade tolerant plants for your woodland gardens that bloom through the summer and into the fall. In today’s article, I’ll talk about some of these and share some images from my shadier gardens. 

Plants that grow under the tree canopy of a forest have to be tough. Not only do they need to compete with tree roots for moisture, they need to be able to collect light that filters through often dense canopies of leaves. Many of these plants collect as much energy from the sun as possible before the trees leaf out, then “coast” on that stored energy for the rest of the summer. But a few plants buck the trend and manage to grow, produce flowers and set seed under shady conditions that few others could tolerate.   

One thing I have observed that almost all these plants have in common is large leaves. They require maximum leaf area to absorb the few photons of light that filter through the trees, with their leaves designed to work at maximum efficiency. (Compare, for instance, the leaf of shade tolerant Asclepias exaltata – Poke Milkweed – to those of the sunny, open prairie species Asclepias verticillata – Whorled Milkweed or of the shade tolerant Lobelia inflata – Indian Tobacco – with the sun-loving Lobelia spicata – Pale Spiked Lobelia). 

Another thing I have noticed these plants tend to have in common is that their flowers are mostly white, green, pale blue or pale yellow (at least until the fall, when a few brighter colours – mostly yellows – appear). Whether this has to do with the plants requiring more energy to produce colourful flowers (speculation on my part) or because in shady areas these colours show up more for the pollinators to find, I have no idea. Two exceptions are the brilliant reds of Monarda didyma (Beebalm) – not normally associated with shade gardens, but it thrives in moist dappled shade in my garden – and Lobelia cardinalis (Cardinal Flower). 

It is the end of July as I write this, and a few late-spring/early-summer shade tolerant plants have now finished blooming and are setting seed. These include Thalictrum pubescens (Tall Meadowrue), T. dasycarpum (Purple Meadowrue), T. revolutum (Waxy Meadowrue) and Asclepias exaltata (Poke Milkweed). 

Monarda didyma (Beebalm) and Lobelia cardinalis (Cardinal Flower) are both in full flower right now in full light shade where they brighten dark corners with a brilliant flash of colour, and attract hummingbirds and butterflies. And new to my shade garden this year, but doing nicely, is the porcelain blue Campanulastrum americanum (American Bellflower). Lobelia inflata (Indian Tobacco, aka Puke Weed) is also flowering now in full (but relatively light), moist shade with delicate, pale bluish flowers. 

Just starting to bloom in my shade gardens are Eurybia macrophylla (Large-leaf Aster), Eurybia schreberi (Schreber’s Aster), Aralia racemosa (American Spikenard), Ageratina altissima (White Snakeroot), Actaea racemosa (Black Cohosh), Scrophularia marilandica (Late Figwort) and Circaea lutetiana (Enchanter’s Nightshade). These are joined by a large patch of Impatiens pallida (Yellow Jewelweed). Even some Veronicastrum virginicum (Culver’s Root), another plant like Beebalm that isn’t normally thought of as a shade tolerant plant, is doing great under the dappled shade of Gymnocladus dioicus (Kentucky Coffeetree). 

We also have some lovely plants suitable for part shade. These would normally be found at the edges of forests, and can tolerate quite a bit of shade. However, many of them tend to flower more prolifically with the benefit of more sunlight. Most books suggest that Solidago juncea (Early Goldenrod) requires full sun, but it is doing well under a large sugar maple in my yard where it gets only a half hour or so of direct, late afternoon sun. As its common name suggests, it is one of the earliest goldenrods to flower and starts flowering in my southwestern Ontario garden around the third week of July.  

A number of other shade plants – mostly asters and goldenrods, but also some interesting woodland species – will start to bloom in the next few weeks but I’ll leave those for a later article. We also have lots of shade-loving ferns, grasses and sedges, and a few great shrubs for shade, but those, too, will have to wait. 

Note that none of the plants listed above will thrive in deep shade such as that often found under Norway Maple, evergreens (like spruce or cedar) or close to the north side of a building, but they will all do very well in dappled shade (from less dense canopies such as under Kentucky Coffeetree) or if planted near the edge of the shade where they can get sun for at least part of the day.  If you do have deep shade, you may want to consider some of our spring ephemerals mixed with ferns, for now. 

Happy native plant gardening. 

Pollinator Gardens and Bee Stings 

A growing gardening trend is to plant pollinator gardens, often using native plants, to attract and feed bees and butterflies. This is occurring as a response to the news that our bees and butterflies are quickly disappearing. This realization likely started because honey bee farmers were faced with major financial losses as a result of Colony Collapse Disorder (CCD) starting in the early 2000s. Around the same time, folks began noticing that Monarch butterflies were in trouble. It wasn’t long till we also began to realize that our native bees were disappearing, too.  

Honey bees are native to Europe and are really just another form of agricultural livestock, like cattle or hogs or poultry. Their loss, though economically difficult for honey producers, would not have the same ecological impact as the loss of our native bee species. After all, we likely have as many as 4,000 species of bees native to North America and these insects are critical for the successful pollination of most of our flowering plants – including much of our food. Many of our native bees are specialists, relying on one or a very few different kinds of plants. (Honey bees, on the other hand, are generalists – they will collect pollen from just about any plant.)  

So to “save the bees” people have started growing native flowers, and creating pollinator gardens. These can be small backyard oases, restored farm fields, or educational gardens in parks, commercial areas or in school yards. However, a concern that often pops up – especially in school yards – is that with all those flowers, children are going to get stung. 

People have a natural aversion to bee stings. And for good reason – they hurt. Some folks are severely allergic and must carry an epi-pen when they go outdoors.  

When I was about 4 years old, my parents rented a farmhouse out in the country. At the end of a very long laneway (exceptionally long for a four-year-old) were two old, old apple trees. I saw what I thought were yellow “manure-flies” (at four I wasn’t very discerning). They were swarming between the two trees and I thought it would be fund to run through them and scatter them. My little four-year-old legs could not carry me up the long hill to the house fast enough and I got many nasty stings. Fortunately I don’t seem to be overly allergic. 

Fast forward 15 years, and I am a counselor at a summer camp and am tasked with removing the bumble bee nest under the front step of one of the cabins. As I bent over to observe the results of my destruction, a bumble bee found my backside. I literally could not sit on that cheek for a week.  

Fast forward another 50 years and I had to remove a homemade compost bin (made from old pallets) so an arborist could take down a couple of large mulberry trees. Halfway through the pile I discovered that 3 different species of flying insect had taken up residence in the pile – one looked like some form of bee, but the other two were obviously wasps (I didn’t stick around long enough to make a proper ID). My old 65-year-old legs could not carry me up the hill in my yard to the house fast enough to avoid getting a number of stings.  

These three incidents are probably the most memorable of my encounters with bees and wasps, but by no means are they the only times I’ve been stung. And yet I plant lots of pollinator gardens in my yard and even though I get up very close and personal while I’m photographing the bees, I have never been stung or even threatened while around the flowers. (The one exception was when I inadvertently rested my weight on my hand on top of a ground nesting bee trying to exit its home – however, the sting was no worse than a fly bite and never even swelled up. I took it as simply a warning to “get off me”.) 

So what is the real risk of getting stung around a pollinator garden? I would contend that it is exceedingly low. You are probably more likely to get stung walking down the sidewalk or opening your garden shed door. This is for a number of reasons.  

First of all, most of our native bees are solitary. Many don’t even have stingers. And when they’re busy foraging amongst the flowers, they are not paying any mind to the large mammal (the human) that is nearby. This holds true even for the bees with stingers, such as honey bees and bumble bees (only the females of these species sting, by the way). Bees normally only sting if they feel threatened or if they are accidentally (or deliberately) molested or provoked. 

Several wasps and hornets, on the other hand, live in colonies and are very territorial. They will sometimes sting if you simply get too close to their nest. (The yellow “manure flies” and the insects in my compost pile that stung me were all almost certainly wasps of some type and were simply protecting their colony.) Paper wasps, mud wasps, etc. like to build their nests in human-made structures – like your garden shed, or your garden-hose hanger, or even on your garage eaves. This is where you’ll most likely encounter these territorial insects, and where you’re most likely to get stung. 

Another reason you’re unlikely to be stung around pollinator gardens is that bees and most wasps have very different diets. Many wasps are carnivores, filling their need for protein from insects (or in the fall, your picnic dinner). So the critters that are apt to sting you just for getting too close are not the ones that are going to be busy around your pollinator garden. (Some wasps DO hang around flowerbeds, drinking the nectar, but I have never found any of these to be the least bit aggressive.) 

So, if your child’s school, or your employer, or your neighbour, decides to put in a pollinator garden to help stem the decline of these extremely important insects, you needn’t worry about getting stung. A little bit of care and some education can make this a win-win scenario. And if you or your child is highly allergic – just remember to carry your epi-pen. And keep in mind that the pollinator garden is a very unlikely source of bee stings. 

Happy Native Plant Gardening. 

Why I Grow Native Plants 

This month’s article is going to get personal. It won’t be a “how-to” or a “what to grow where” blog. Instead, I’ll share a bit of my personal journey into native plant gardening – a journey that has gone from curiosity to complete addiction. 

I was lucky as a kid in that we often lived in rural areas and, when we didn’t, I had my uncle’s farm to visit for the entire summer holidays. We also camped a lot. Because we moved around a lot, I didn’t develop many long-lasting friendships and so I became a bit of a loner. But I had Mother Nature around me as a friend so I was quite content.  

My brother (left) and I (right) during one of our many childhood camping experiences that gave us a great appreciation of the natural world (photo likely taken somewhere around 1960, give or take a year or two).

Fast forward a few decades and I went off to university (in my 40s) and enrolled in a BSc in Environmental Sciences degree program where I took a major in Natural Resources Management and a minor in Landscape Ecology. This was followed by a master’s degree in Environmental Biology. After graduating from there, I took a year of Advanced GIS Applications (computer mapping) and at the sweet young age of 50 I was ready to start life over with a new job, a new mortgage – and a pile of student loans to pay off. I managed to get a job in Ridgetown, Ontario at a satellite campus of the University of Guelph that allowed me to teach part time, eventually becoming a full-time teaching gig.  

After a couple of years of getting my life in order, it was time to start gardening again. I had been an avid gardener – veggies, mostly – most of my life. I started, as many do, by planting the things I knew – hostas, tea roses, tulips, and (I shudder to remember it) periwinkle, goutweed, and some other nasties.  

Then, one day, I saw a packet called “Wildflower Mix” and thought these might be nice. After all, I grew up with lots of wildflowers around me on the farm and when camping. At this point I still didn’t realize that wildflowers and native plants weren’t necessarily the same thing. 

The next year when things started popping up in the garden that I knew were European in origin, I started doing my homework. To my surprise (and, in some cases, disappointment) I found out that many of my favourite flowers in the fields of my childhood were also of European or other origins – garden escapees like chicory, mullein, teasel, and so on. And that packet of wildflower seeds? Of about 12 species, only one was native to where I live and a second one was a ‘near native’. 

I decided to remove the non-natives from that new flowerbed and plant some true natives – goldenrods, beebalm, black-eyed Susan – and it wasn’t long before I started seeing that these new flowers had WAY MORE bees and other insects on them than the non-native ones did. And I started buying books about growing Native Plants – like Lorraine Johnson’s “100 Easy to Grow Native Plants” and “Grow Wild”. 

In the beginning, I still gardened with my old gardening aesthetic – I bought plants that looked exotic (including a few cultivars like “Hello Yellow” butterfly milkweed, an almost purple cardinal flower, etc.) But the more I read, the more I began to appreciate that true species often provide more benefit to wildlife than their cultivars do.  

Soon I had a second bed of natives, then a third, and eventually all the non-native plants and cultivars had been removed from my half acre back yard and replaced with natives or “near natives”. There are few thrills as satisfying as standing in front of a bed of flowering wild bergamot watching at least a dozen different species of bees, some wasps, butterflies and the fabulous clearwing hummingbird moth all busy collecting pollen and/or nectar. Or witnessing the perfect relationship between the giant black digger wasp and dotted horsemint (Monarda punctata) – check out my blog on that plant to learn more about these two. 

The more I learned, the more I planted. The more I planted, the more I wanted to share my discoveries and newly-gained knowledge. Pretty soon my focus was no longer on what I found particularly pretty, but what provided the most benefit to insects and birds.  

By the time I hit about 250 species of natives and near natives in my yard, I started to look for some of the rarer plants for which I might be able to provide a healthy seed bank. Whenever possible, I buy almost exclusively from reputable native plant nurseries.  

At last count (I am a spreadsheet guy, after all), even after I had over 20 species that didn’t make it through this past winter, I still have well over 320 species of native flowers, grasses, sedges, shrubs, vines and trees in my gardens – which have now expanded to the front yard as well. And I have a wish list of plants that is way bigger than what I can possibly find room for in my yard (well, perhaps I can squeeze them in somewhere).  

And because I like to share what I’ve learned (as any good teacher does), I open my gardens to organized garden tours a few times a year and I talk to groups and anyone else who will listen about the benefits of growing native plants. 

I’ve often joked that it’s an addiction – but what better addiction than growing beautiful native plants that feed the insects that feed the birds, or that provide seeds directly to the birds. It’s my little payback to Mother Nature for all she taught me when I was young.  

Happy Native Plant Gardening 

Rick 

Boulevard Gardens

A Note on Boulevard Gardens 

Most suburban, and some urban, yards have a narrow grass strip between the sidewalk and the street. Invariably the municipality requires you to maintain this strip despite it being their property. And because it is their property, they often have restrictions as to what you can or can’t do with it (always check with your municipality before creating a boulevard garden). Some of these restrictions make total sense – like the ones that say don’t plant tall things that will block driver and pedestrian visibility, don’t plant tall shrubs or trees that may interfere with overhead wires, or don’t place large boulders that could interfere with maintenance (including snow removal) equipment. In addition, because it is municipal property, municipal work crews have a legal right to access it any time for maintenance of overhead or underground infrastructure, or when repairs to sidewalks, curbs and streets are necessary. As a result, your nicely tended flower bed could be unavoidably trampled. 

A couple of blocks from me, someone planted a tiny blue spruce in the median a few years ago. It is directly under the power lines, and pretty soon the branches will be blocking the sidewalk and extending into the street. I can’t imagine the municipality will be letting it go much longer. I’m surprised it has stayed this long.

So, what CAN you do with this area – an area that I have often seen referred to as a “hell strip”. These strips get this reputation because they are often comprised of compacted fill from when the street and/or sidewalk was put in. They get salt deposited when snowplows push snow onto them. Melting snow and contaminated street water get splashed onto them when cars drive by. And they’re very handy spots for pets to “do their business” when being walked. It’s a wonder anything grows there at all. 

However, if properly planned, these otherwise boring grass strips can provide year-round natural beauty, excellent pollinator habitat, an opportunity to educate your neighbours, and can even reduce maintenance – no weekly lawn cutting is necessary.  

But you need to choose your plants wisely. Boulevards require plants that not only tolerate the shade/sun/moisture conditions that may be present, but also a certain amount of salt accumulation, dog urine and even some trampling by pets and neighbourhood kids, all while meeting stringent height restrictions. These plants have to be extra tough. But we have lots of native plants to choose from (a very abbreviated list at the end of this article provides just a few examples). 

Creating the Boulevard Garden 

Call before you dig. Often utilities are buried in, or very near to, boulevards. Telephone (now usually used for your internet) and cable lines, in particular, are often buried in very shallow trenches – more often than not by simply inserting a spade into the ground and dropping the line in. Pushing your shovel into the ground can easily sever these wires (I speak from experience!).  

Some municipalities require you to apply for a permit and there may or may not be a cost associated with this. Depending on where you live, the municipality has the right to rip out unauthorized plantings on their property and even bill you for the labour involved. So check very carefully – you can usually find the information on the municipality’s website. 

Once you get permission and know your municipality’s rules on boulevard gardens, and your utilities have been located, you can start to plan the garden.  

What do You Have to Work With? 

Let there be light! 

First of all, determine the general conditions of your hell strip. Is it full shade, part shade or full sun? One way to figure this out is put a couple of stakes in the ground where you want to plant, then check it mid-morning, noon, and late afternoon so see how much light the plants will get. This will greatly narrow the selection process for picking your plants. Although it is not a hard and fast rule, most sources will say that anything greater than 6 hours of direct sun is considered full sun. Part sun (or part shade) is usually considered as 4-6 hours of sun. Full shade does not mean NO sun as most plants require some sunlight, even if it is diffused or dappled. Full shade usually means 4 hours of sunlight or less. 

All the Dirt 

Is the underlying soil clay, sandy, or construction rubble? This will likely depend on a LOT of things – how old your neighbourhood is, how recently the streets and sidewalks had a major repair (such as sewers being dug up), and what the parent soils are.  

It might take a bit of research, but you can find out your soil type by Googling ‘Soil Maps’ and your province/state (sometimes even municipalities will be able to provide this info).   

You can also dig a hole and do a percolation test – these are regularly done for septic beds to determine the size of bed needed – and use the results to determine soil type. To do the perc test, dig a hole 15 to 30cm deep, fill the hole with water a few times and let it drain out to saturate the soil (this could take a several hours – especially if you have heavy clay). Put a ruler in the hole that extends to the top and fill the hole with water again and monitor how long it takes for the hole to empty (be patient, this is a slow process). 

If the water infiltrates 20-30 mm/hr, the soil is sandy loam. If it only goes down 10-20 mm/hr, you have loam soil, 5-10 mm/hr is clay loam, and if the water only drops 1 mm/hr then you know you have clay soil. (I did say it was a slow process.) 

Another way to determine soil type is by doing a ribbon test. A soil expert can do this with confidence, but I always find the ribbon test to be quite subjective. There are great videos online on how to do a soil ribbon test and how to interpret it if you want to try that. 

My boulevard is extremely wide, which gives me a lot of planting room. (I took this photo many years ago, before I discovered native plant gardening – all the non-natives in this boulevard garden are now long gone!)

Wet or Dry? 

Are you on the top of a hill where all the water will run away? Are you at the bottom where it will collect? I’m at the top of a knoll and have a very wide boulevard, but it was contoured as a shallow ditch to take water away. Unfortunately (or maybe fortunately) my neighbour’s drive is raised enough that in very heavy downpours water can accumulate. In my case it doesn’t last long as I have very sandy soil, but if this was clay soil, I’d have a mini lake every time it rained and would need to find plants that could stand having their feet wet for extended periods. If you are on sandy soil, with full sun, you are going to be limited to prairie species that can tolerate drought. If your boulevard is well shaded, especially if you have heavy clay soil as well, you won’t be able to grow typical prairie plants at all. 

What Grows Well in a Hell Strip? 

As promised, here are a few plants that are tough enough for the most common boulevard conditions, are typically 3’ (1m) tall or less, sorted by growing conditions. This list is by no means exhaustive but is meant just to get you started.  

Dry, well drained soils, full sun 

Full sun garden requires drought tolerant, tough plants. Photo courtesy of Donna Slater.
  • Achillea millefolium (Yarrow) 
  • Aquilegia canadensis (Wild Columbine) 
  • Asclepias tuberosa (Butterfly Milkweed) 
  • Bouteloua curtipendula (Side-oats Grama) – grass  
  • Ceanothus americanus (New Jersey Tea) – shrub 
  • Coreopsis lanceolata (Lance-leaf Coreopsis) 
  • Eragrostis pectinacean (Purple Lovegrass) – grass 
  • Fragaria virginiana (Wild Strawberry) 
  • Geranium maculatum (Wild Geranium) 
  • Geum fragarioides (Barren Strawberry) 
  • Geum triflorum (Prairie Smoke) 
  • Penstemon digitalis (Foxglove Beardtongue) 
  • Penstemon hirsutus (Hairy Beardtongue) 
  • Pycnanthemum virgianum (Virginia Mountain Mint) 
  • Rudbeckia fulgida (Orange coneflower) 
  • Rudbeckia hirta (Black-eyed Susan) 
  • Schizachyrium scoparium (Little Bluestem) – grass 
  • Solidago nemoralis (Gray Goldenrod) 
  • Solidago rigida (Stiff Goldenrod) 
  • Sporobolus heterolepis (Prairie Dropseed) – grass 
  • Symphyotrichum oolentangiense (Sky-blue Aster) 

Dry, Shade to Part Shade 

Part sun/Part shade usually means 4-6 hours of direct sun each day. Photo courtesy of Donna Slater.
A narrow, part shade garden that will eventually become full shade as the trees mature. Photo courtesy of Victoria Hunter Williams.
  • Antennaria parlinii (Parlin’s or Smooth Pussytoes) 
  • Asarum canadense (Wild Ginger) 
  • Asclepias exaltata (Poke Milkweed) 
  • Campanula rotundifolia (Harebell) 
  • Elymus hystrix (Bottlebrush Grass) – grass 
  • Eurybia macrophylla (Largeleaf Aster) 
  • Geranium maculatum (Wild Geranium) 
  • Geum fragarioides (Barren Strawberry) 
  • Oenothera biennis (Evening Primrose) 
  • Penstemon hirsuta (Hairy Beardtongue) 
  • Phlox divaricata (Wild Blue Phlox) 
  • Polygonatum biflorum (Solomon’s Seal) 
  • Tiarella stolonifera (Foamflower) 
  • Solidago flexicaulis (Zigzag Goldenrod) 
  • Solidago ptarmicoides (Upland White Goldenrod) 
  • Viola pubescens (Downy Yellow Violet) 

Heavy Clay Soils, Full Sun Part Shade 

  • Achillea millefolium (Yarrow) 
  • Allium cernuum (Nodding Wild Onion) 
  • Asarum canadense (Wild Ginger) 
  • Asclepias incarnata (Swamp Milkweed) 
  • Carex blanda (Common Wood Sedge) – sedge 
  • Carex glaucodea (Blue Wood Sedge) – sedge  
  • Coreopsis lanceolata (Lanceleaf Coreopsis) 
  • Elymus hystrix (Bottlebrush Grass) – grass 
  • Fragaria virginiana (Wild Strawberry) 
  • Geranium maculatum (Wild Geranium) 
  • Geum fragarioides (Barren Strawberry) 
  • Monarda didyma (Beebalm) 
  • Monarda fistulosa (Wild Bergamot) 
  • Pycnanthemum virginianum (Virginia Mountain Mint) 
  • Rudbeckia fulgida (Orange coneflower) 
  • Rudbeckia hirta (Black-eyed Susan) 
  • Solidago flexicaulis (Zig-zag Goldnerod) 
  • Symphyotrichum lateriflorum (Calico Aster) 
A full shade garden gets less than 4 hours of sun a day. This full shade garden is thriving with the right mix of shade plants. Photo courtesy of Pete Ewins.

A special thank-you to all the folks that offered up photos of their boulevard gardens to make this article possible.

Happy Native Plant Gardening 

Got Shade? The Spring Ephemeral Garden 

It is April. Finally, depending on where you live, the snow is mostly gone, the days are getting wonderfully warmer, and the first flowers of spring are braving the cold nights and providing a source of nectar and pollen for the earliest of pollinators. Many of these early flowers bloom for a very short time and, surprisingly, many are found in shady forested areas. This is likely because in the forest they need to grab pollinator attention before the tree canopy fills with the leaves of summer, before the forest floor becomes dark and photosynthesis there slows.  

Once the canopy fills in, many of the forest floor flowers simply become dormant, disappearing beneath the soil, waiting till spring comes again. Ephemeral means “lasting for a very short time” and perfectly describes these forest dwelling plants. But though they only bloom for a short time, they are no less valuable in the garden if for no other reason than they are often the first signs that summer is coming. 

Because of the short growing season on forest floors, and thus the brief period they have in which to store energy in their roots or corms, many spring ephemerals take a long time to mature. Some, like Trilliums or Jack-in-the-pulpit, can take two or more years before the seeds send up their first leaf, then another 5-8 years (or more) to produce their first flower.  

Another thing I find fascinating about these plants is that many of them produce seeds with a fleshy, high protein attachment called an elaiosome. These nutritious little bundles are a favourite of ants, who cart them back to their dens, eat the elaiosome and discard the seed. This is an effective form of seed dispersal. I haven’t quite figured out why this strategy seems more common with woodland spring ephemerals than with other plants, but that, at least, has been my experience.  

Some of these plants are truly ephemeral in that they pop up, bloom, and disappear completely till next spring. These are plants like the Spring Beauties (Claytonia spp.), Dutchman’s Breeches and Squirrel Corn (Dicentra cucullaria and D. canadensis), the Toothworts (Cardamine concatenata and C. diphyllum), Virginia Bluebells (Mertensia virginica) and Wild Leeks – aka Ramps (Allium tricocuum). The plants are not dead, though, they are simply hibernating belowground till the sun reaches them in the spring. If adding these to your garden, planting ferns amongst them will help to fill up the space once the flowering plant disappears for the summer. 

The Wild Leeks are a bit unusual in that the leaves come out first, collect as much energy as they can while the sun can reach them, then all disappear. A month or so later they will then send up a stalk with a small white globe of flowers that attracts early summer pollinators. By late summer these stalks will hold a head of black seeds and, if you know what to look for, you can collect a few of these seeds for your garden. But, like Trilliums and Jack-in-the-pulpit, the seeds can take up to 2 years to break dormancy, and several more years before they flower. And they are very slow growers so patience is required. (It is also the reason you should not dig them up in the wild as it can take many years to replace each plant.) 

Another group of plants usually lumped in with spring ephemerals are the ones I think of as “pseudo-ephemeral” because they flower early, produce seed, then fade into the background as just leaves and stems. These include Trout Lily (Erythronium americanum), May Apple (Podophyllum peltatum), Foamflower (Tiarella stolonifera) or the Hepaticas (Hepatica acutiloba and H. americana). For some of these, like the May Apple and Trout Lily, the leaves may persist through mid-summer, but are usually gone by the end of the summer – depending on how hot and dry the summer is. Others, like the hepaticas, hold on to their leaves right through to the following spring – giving them an early start at photosynthesizing as soon as the snow disappears. 

There are many more of these lovely spring flowering plants for your shade garden, of course, as well as others that flower through the summer and into the fall – violets, Wood Poppy, Zig-zag and Blue-stemmed Goldenrods (for the fall) and even Blue Woodland Phlox – but I’ll leave the summer and fall shade plants for another article. For some other spring-flowering woodland species, check out Blood Root (Sanguinaria canadensis), Early Meadowrue (Thalictrum dioicum), Large-flowered Bellwort (Uvularia grandiflora) or, if you have a wet enough shade garden, the exotic EXTREMELY early flowering Skunk Cabbage (Symplocarpus foetidus) – which often starts blooming as early as February or March in my part of the country, generating its own heat and melting the snow around it. 

If you have a shady spot that gets early spring sunshine, you can brighten it up, even for a short while, with some of these lovely spring ephemerals. 

Happy Native Plant Gardening. 

On Native Plant Range Maps 

Have you ever thought about the fact that almost all books on native plants define their ranges as “Native in the Northeastern US and Southern Canada”, or “Native in the Midwest States and Southern Prairies”? Very few plants are native throughout those rather large areas of geography. Soil type, microclimates, even underlying geology can have a great influence on which plants would be found naturally in any given location. Wouldn’t a map be much more accurate and useful? After all, native plant gardeners, more so than any other, want to know if a plant is actually native to where they live. In this month’s article I will try to explain why range maps are not very common, why they are a challenge to create, and why they can be a challenge to interpret.  

There are at least 3 reasons why range maps are rarely found in the guides. The first of these is that, with the exception of a few plants that have been studied extensively (e.g. Goldenrods in the Astereae Lab at the University of Waterloo), a lot of the native plants we want to grow in our gardens have historically garnered very little interest from a geographical perspective. We may have studied the ecology of the plant (how it interacts with its environment), its physiology, and in some cases we may even have brought it into the greenhouse to produce cultivars. But, for the most part, we’ve been more concerned with the plant itself than with knowing where to find it (beyond what kind of soil/light regime it can be found in – prairie, forest, etc.). This means that we just don’t have readily available data to create reliable range maps. 

The second problem is that the collection of locational data to determine native ranges is, by necessity, a historical one. In the past 150-200 years we have moved plants all over the place, well beyond their native ranges. This means that it is a lot trickier now to determine if that plant has always been here, or if it has just escaped from someone’s garden. We rely on early botanists’ recordings of what they saw, and where they saw it.  

However, even though the historical records are extensive, they aren’t always 100% accurate. Modern botanists often debate whether so-and-so’s sighting of this plant or that accurately represent where the plant was found before Europeans arrived. Echinacea purpurea, for instance, is usually considered native in parts of Michigan, but some argue that the historical records indicate it was only found in areas not far from railway corridors. Does this mean those plants were simply the result of seeds brought in inadvertently by rail? Or maybe that their mapped location is a case of the botanists recording those sites, but not venturing further afield to see that the plant existed elsewhere. Keep in mind that at the time many of these botanists were working, there were few roads and lots of wilderness. 

The third, and perhaps biggest challenge, is determining what scale to use to map the ranges. Some maps are created at a small scale (i.e. they cover a large area). By necessity, details get obscured at these scales. If we map, say, the range of Agastache scrophulariifolia (Purple Giant Hyssop) at the North American scale, as shown in the 1945 map from The American Midland Naturalist journal (Vol 33, No. 1), we can see that the mapping is very generalized and doesn’t take into account variations in local landscapes or microclimates. 

At the other end of the spectrum (large-scale mapping), we are zoomed in close (so everything looks larger – hence its name), but these maps have their own issues. Perhaps the biggest of these is that many people looking at such a map believe that the boundary shown is a hard boundary – that the plant is definitely found on one side of the line and not found on the other side of it. Therefore the map-maker runs the risk of using vague data to create the illusion of clear and precise knowledge. As a former map-maker, I know only too well the challenges.  

It is extremely difficult to generate a map showing where a plant was native over a large area and yet still capture small isolated pockets. In the map I created (below) for Green Milkweed (Asclepias viridiflora), you can see that it covers a large contiguous area in a band from southern Lake Michigan, crossing southern Ontario, into Ohio, Pennsylvania and beyond (shown with striped shading). Yet if you look closely, you’ll see a couple of small pockets of stripes – one further north along the Lake Michigan shoreline, and another just north of Manitoulin Island in Ontario. The second of these locations, in particular, is extremely exaggerated in area. In fact, the plants were only found in a small, isolated area that would not even have shown up at the scale of this map. The dilemma is, then, whether to exaggerate the area, or to leave the impression that the plant was never found that far north.  

When you combine all of these reasons, you get a better feel for the amount of work involved to 1. verify the native ranges, and 2. determine what scale to map them at, and what information to include or leave out. All such maps, by necessity, are generalizations because you can’t easily account for small, localized variations. As a result, few people have tried to do it.  

Then, of course, there is the whole business of interpreting the range maps once they ARE made. The authority I use to determine if a plant is native to Ontario is the Database of Vascular Plants of Canada (VASCAN). However, all the maps on their website show nothing more than IF the plant is native SOMEWHERE in Ontario. For instance, Pulse Milk-Vetch (Astragalis tenellus, aka Astragalis multiflorus) is shown as native to Ontario. However, that is based on one, small, localized occurrence in northern Ontario, as shown in this map from the Atlas of Rare Vascular Plants of Ontario

South of the border, plant species have been mapped to the county level, in most states. However, it is often unclear if these maps represent current locations or historical (i.e. native) ranges. In the map of the same plant (identified as Astralagus multiflorus) from the Biota of North America Program (BONAP) website, the bright green indicates the counties where the plant is known (in the US) but in Canada that level of mapping has not been done, so the entire province of Ontario is shown in dark green.  This could lead some people to think that it is found throughout the province.  

Before you can decide that a plant is native to where you live, you need to check multiple sources and put together a picture. For those in southwestern Ontario, at least, an excellent resource is Michael Oldham’s 2017 “List of the Vascular Plants of Ontario’s Carolinian Zone (Ecoregion 7E)” that you can download here. It gives a county-by-county breakdown of where the plants are considered to be native. 

Shaun Booth (from In Our Nature) and I have been working on a reference book for native plant gardeners and we have taken on the task of mapping the native ranges for over 200 species of plants in the southern Great Lakes region. Over the past 4 years or so, we have compiled historical records as well as on-line data, and then worked with expert ecologists in the province and adjoining states to verify our maps. We are currently working on finding a publisher so that you, too, can have access to this information. Wish us luck. 

Are My Plant Seeds Native Enough? 

There’s a lot of activity on the various native plant gardening Facebook groups these days about winter sowing.  I’ve never tried it, but it makes total sense to do what Mother Nature does – set your trays of soil with seeds outside and let the natural refrigeration of winter do the cold moist stratification for you. 

In my research for native plants sources, I have come across a handful of companies that specialize in native plant seeds. In fact, some ONLY sell seeds and not plants. 

Have you ever asked yourself where they get the seeds? Does it even matter? A milkweed is a milkweed, regardless of where it is growing, is it not? Well, that depends. 

Rare Native Plants 

In southwestern Ontario, where I live, we are in what is often referred to as the Carolinian Life Zone. Here our climate and soils are similar to places far south of us – as far as the Carolinas in the US. That means that many plants are native here that aren’t found naturally anywhere else in Canada.  It also means we’re at the northern limit for many of these plants, and occasionally the populations of these plants are found only in isolated pockets here and there.  

Take, for example, Stylophorum diphyllum, or Wood Poppy, known to be found naturally only in a few isolated locations around London, Ontario before we started spreading it through our gardens.  

Or what about Cercis canadensis, the Eastern Redbud, a beautiful small tree originally known only from Pelee Island in Lake Erie (Canada’s most southerly point – at the same latitude as northern California). However, because of it’s size and spectacular spring colour it now adorns many yards throughout southwestern Ontario and even points north and east of here. 

Two Sides to the Argument 

There are two sides to the argument about whether this is a good idea or not, and I still haven’t entirely made up my mind which side I’m on. Both sides have much merit. 

The first argument is that these isolated pockets may hold unique genetic traits that could disappear though cross-breeding with plants that evolved elsewhere. And until we have done genetic testing to show otherwise, we should not introduce these other plants. To loosely paraphrase Joni Mitchell, “We won’t know what we’ve lost if it’s gone”. 

At the other end of the spectrum, there is the argument that rare, isolated pockets of such plants are in danger of being lost due to habitat destruction, climate change, pollution, etc. and that in order to keep seeing them, we need to plant more. After all, humans are the main reason many have disappeared over the last 200 years, or are on the brink of disappearing now. And since there are so few left in the wild here, we need to source the seeds elsewhere.  

The other argument for bringing seeds or plants in from other areas is that very small, isolated pockets of plants may reach a genetic bottleneck where inbreeding can lead to weakened plants that are more susceptible to the stressors that are placed on them. Only by bringing in outside plants can we bolster the genetic diversity and, hopefully, stave off extinction.  

Native Plant Sources – Choices 

I recently placed an order for some seeds from a company in Ontario because they were the only company offering the plant I have been looking for for some time. I was told the seeds for my plant were ethically sourced in Ontario.  

However, for another plant I was curious about, I was informed the seeds were from the US. They ignored my question about WHERE in the US, but my guess is that it was likely Prairie Moon Nursery in Minnesota as that is one of the larger sources of native plants seeds and many nurseries here in Ontario use seeds from there.  

The latitude of Minnesota is roughly the same as southern Ontario so those plants should be hardy here. However, the original stock from which those seeds were sourced may be genetically quite different than the ones that actually evolved here. It has been reported that Asclepias tuberosa – butterfly milkweed – plants tend to be a lighter yellow in the west and a darker orange in the east. By the same token, Ratibida columnifera (not actually native in Ontario) – sometimes called Mexican Hat – is mostly pure yellow in Canada but mostly a burnt red in the southern end of its range. By bringing in different genetics, we may lose the plants that have evolved here, and any uniqueness they offer. 

Another native Ontario plant from my wish list that this company offered for sale was out of stock. I was shocked, though, when they said they were just waiting on their shipment from England. What? A native Ontario plant and it is being sourced from across the ocean?  

A few years ago, someone told me that seeds for a plant I was looking for was available on Amazon. After doing a bit of digging, I discovered that these seeds were “shipped from China”. I didn’t buy them.  

All of this is to say, whether you’re winter sowing or spring sowing, ASK where your seeds came from. If there just AREN’T any seeds or plants available for that one plant you really MUST have, only you can decide what limits you’ll set on the acceptable distance from where you live to where they are sourced from. As the demand for native plants continues to grow, local sources will continue to pop up. If they know that the provenance of the seeds is important to native plant gardeners, they will look closer to home to source their seeds. And eventually (I hope) more local farm operations will start to grow native plants to supply the market with seeds. 

In the photo below, the Irvine Ranch Conservancy in California is one of many commercial native-plant producers in the US (photo courtesy of Irvine Ranch Conservancy). I was unable to get a photo from a local commercial producer in time for posting. This level of production is possible here, too, and will happen if we demand local seeds.

Happy native plant gardening. 

Gateway Plants

Gateway Plants, or How to get your neighbours addicted to growing native plants 

A couple of native (and one “near native”) gateway plants in my southwestern Ontario garden.

Most people have heard the term “gateway drug”, referring to habit forming drugs like marijuana or alcohol whose use is thought to lead, in some people, to the use of other more addictive drugs. Well, in the native plant gardening world we’re always searching for the “gateway plants”, those plants we can convince our neighbours to grow that, we hope, will lead them to become addicted to growing native species in their gardens. 

At the suggestion of a close friend (and fellow native plant gardening addict), I thought I’d use this month’s article to discuss what I think makes a good gateway plant that you can grow and share so that your neighbours, too, will be hooked on growing natives. 

What Makes a Good Gateway Plant? 

In my opinion there are 3 things a native plant must have to get non-native gardeners hooked on growing them. 

  1. They must be showy, colourful or otherwise attractive (foliage, structure, etc.) and not too tall 
  1. They must be easy to grow and not overly fussy about soil conditions 
  1. They must attract lots of insects and other pollinators so that the new “recruit” receives the reward of seeing the good the plant is doing. 

Creating a Convert 

You probably know someone, a neighbour or family member, that is into gardening but still thinks petunias, bleeding hearts and hostas and other non-natives are the only things to grow in their flower beds. So how do you convince them to try some native species in their garden? For some, it will be an easy sell – show them the beauty, easy maintenance and wildlife value and they will become converts. For the others, it may take a little longer. But the easiest way will be to share some of your best gateway plants and let the plants do the persuading. 

One day, a few years ago, a friend who had beautiful gardens of Crocosmia, Bearded and Siberian Iris, Tulips, Asiatic Lilies, and dozens, if not hundreds, of other non-native species, stood in awe of the swarms of bees, wasps, butterflies, moths and dragonflies that congregated on my Wild Bergamot, Cylindrical Blazing Star and other native plants and, later, on Goldenrods, Pearly Everlasting and Asters. I offered her a couple of my plants, assuring her that they would not take over her garden. The next year I gave her a couple more, and then some more again the year after that. A few years later, and now I am being gifted native plants from her garden – ones I didn’t have.  

A beautiful garden, but with very few – if any – native plants.

My TOP  5 favourite Gateway plants 

There are many native plants (in southern Ontario) that meet my 3 criteria of a good gateway plant – showy, easy to grow, and pollinator magnet – too many to list here. But there are a few outstanding ones, in my opinion, and I will share the reasons for my choices with you. 

1. Scarlet Beebalm 

My absolute favourite gateway plant is Mondarda didyma – Bee Balm (sometimes referred to as Scarlett Beebalm). This plant is not only a bold, brilliant red that brings lots of oohs and aahs from passersby, but it is one of the easiest plants to share. Its shallow roots form a mat right at the surface, and all you have to do is grab a handful, dump them in a plastic bag, and hand them over. They take extremely well to sandier soils, but also do well in clay. They thrive in full sun, but also handle part shade, and even do well in full shade in my garden where they brighten an otherwise dark corner. (The added bonus is that in full shade they bloom later thus extending the blooming period.) They are extremely drought tolerant once established and I have successfully transplanted them in early spring, in the heat of July and August, and even in late fall after they’ve gone to seed. In my opinion, there is no easier plant to share.  They are host plant for the caterpillars of the orange mint moth, the raspberry pyrausta moth and the hermit sphinx moth, among others, and a nectar source for butterflies, bees and even hummingbirds. 

After Monarda didyma, it gets a little tougher for me to pick a second, then third, etc. favourite, so the following are really so close to being equal in my mind that I list them here as much by ease of finding them as anything. 

 2. Swamp Milkweed 

Asclepias incarnata, or Swamp Milkweed, is a very easy to grow, and very well behaved milkweed. Its beautiful pink and white flowers attract lots of pollinators and, despite the “swamp” in its name, it tolerates a wide range of soil types and moisture regimes. It prefers moister soil, and grows very well in my constantly wet bog garden, but it also thrives nearby in dry, sandy soil. And it grows beautifully in a friend’s heavy clay soils as well. Like the Bee Balm, it also prefers full sun, but it does just fine in part shade, too. This is an awesome plant to share with someone who might be thinking about creating a rain garden. It is easily started from seed or by dividing an existing plant. And, of course, they are the host plant for our beloved Monarch butterfly. 

3. Orange Coneflower 

I’ve written about Rudbeckia fulgida (Orange Coneflower) and its lookalikes – R. hirta and R. triloba – in a previous article (see the article “Time for a Black Eye”) and you can learn all about its characteristics and how to grow it there. It is really only native in the very southwest of Ontario in the Windsor/Essex area, but a good substitute in the rest of southern Ontario is R. hirta, the common Black-eyed Susan. What I like most about Orange Coneflower is that it is readily available at nurseries (though often as the cultivar “Goldsturm”), it produces a mass of long lasting, bright yellow flowers, and tolerates a wide range of growing conditions. And it is a perennial (though R. hirta, being an annual/biennial, readily self seeds and maintains itself quite nicely). This plant can be divided in the early spring, though I have also done this successfully in the fall, too. Growing them with Scarlet Beebalm makes a particularly showy display. 

4. Stiff Goldenrod 

Solidago rigida is not your average goldenrod. For starters, it’s not very common in Ontario being native to the Carolinian zone with a known pocket in the Ottawa valley area. But it is quite hardy, has unusual leaves for a goldenrod, and is very well behaved in the garden (unlike some of its goldenrod cousins). It prefers full sun and well drained sandy/gravelly soil but I’ve seen it growing happily in clay-loam and in part shade, though it doesn’t like a lot of tall competition. It’s a great pollinator magnet in the fall, too. It’s rounded, stiff leaves (one of it common names is stiff-leaved goldenrod) and upright form show off the flat-topped cluster of bright yellow flowers in the fall. We hear a lot about the importance of goldenrod for fall pollinators, but folks often think of the very aggressive Canada goldenrod (S. canadensis) when they think of goldenrods. This unusual looking goldenrod is a far cry from that. Plants can be divided in spring or fall for sharing with your neighbours.  

5. Pearly Everlasting 

Last, but definitely not least, on my top 5 list is the drought tolerant Anaphalis margaritacea or Pearly Everlasting. The blue-grey foliage makes this an attractive addition to a flowerbed all season long, but what I really love about it is the constant activity of pollinators while it is in bloom – from June right through till October in my southwestern Ontario garden (I recently posted several photos of pollinators on it on my Native Plant Gardener Facebook page – https://www.facebook.com/RidgetownRick  – all taken in just one photo session). This plant is host for Painted Lady and American Lady butterflies, too, which lay their eggs in late spring/early summer. The caterpillars then make shelters amongst the leaves till they change into butterflies and fly off. A week or two later, the flowers emerge. This plant likes full sun to part shade and dry to medium, sandy-loam soils. This award winning native plant (it received the Award of Garden Merit by the Royal Horticultural Society) will even do well in nutrient-poor soils. It is deer and rabbit resistant and, as the name suggests, is excellent in dried flower arrangements. 

Honourable Mentions 

Some of the many plants that got inched out of the competition for top 5 gateway plants include:

Cylindrical or Ontario Blazing Star (Liatris cylindracea) – a favourite nectar source for Monarch butterflies in particular;

Rough-stemmed Goldenrod (Solidago rugosa) – long sprays of yellow in the fall make this an excellent specimen plant (a cultivar – “Fireworks” – is especially showy). All of these meet the 3 criteria of showy, easy to grow, and excellent for wildlife;

Sky Blue Aster (Symphyotrichum oolentangiense) – a lacy, delicate, soft blue aster with a profusion of blossoms in the fall;

Dotted Horsemint/Spotted Beebalm (Monarda punctata) – an unusual looking plant with showy pink whorls of leaf-like bracts underlying the dotted, yellowish flowers that are a favourite of the black digger wasp; and

Golden Alexander (Zizea aurea) – this early summer flower is a host plant for Black Swallowtail butterfly caterpillars.

Next Steps 

If you aren’t growing some/most/all of these in your gardens now, I suggest you add them this spring. Then you can share some of these ideal gateway plants with your neighbours, and share the addiction. Because, let’s face it, native plant gardening is definitely addictive. 

Happy gardening, 

The Native Plant Gardener 

PS – if you have a special Gateway Plant that I haven’t listed that you’ve had success converting non-native-plant gardeners to native-plant gardeners with, let me know.  

The Boggy, Boggy Dew

Creating a Bog Garden

I am fortunate, as a native plant gardener, to have a ½ acre property with dry shade, dry sun, moist shade, moist sun, and everything in between. Combine this with rich, sandy-loam soil and, for the most part, if I accidentally drop a plant on the ground, it will take root and grow (at least that’s what my friends claim).  This has allowed me to create gardens of deep-shade forest perennials and tall grass prairie, of moisture loving ferns and drought tolerant grasses.  

Escarpment and Waterfall 

In 2012, I decided to take advantage of a slope in my yard to build my “escarpment”, complete with a small pond and a disappearing waterfall. This has provided even more habitat choices where I can now grow things like smooth cliffbrake (Pellaea glabella) – a fern that lives on limestone cliff faces. The pond and waterfalls provide the moisture needed for things like the semiaquatic blue flag iris (Iris versicolor), bog bean (Menyanthes trifoliata) and large leaved arrowhead (Sagittaria latifolia). I even planted some Green Dragon (Arisaema dracontium) this past spring in a pocket of moist soil at the edge of the falls.  

Despite all this variety, I still felt there was something missing so in October of 2019 I decided to build a bog garden where I could grow things like orchids, pitcher plants, sundews and other acidic-moisture loving species that grow in the bogs and wet areas of Ontario. Today’s article is about how I built it and some of the lessons I learned along the way. 

What is a Bog? 

But first, what is a bog (and thus a bog garden). A bog is one of four main types of wetland – bog, fen, marsh, and swamp. Of these, bogs and fens consist of saturated nutrient-poor acidic bodies primarily made up of sphagnum (peat) mosses and peaty soils and very little flow of water. Marshes and swamps, on the other hand, tend to be alkaline with a constant change of water through the system. The main difference between a bog and a fen is that bogs are fed solely by rainfall, whereas a fen receives water through groundwater and surface water, resulting in a slightly less acidic environment (by this definition, my “bog” garden is actually more akin to a fen as there is a constant exchange of “groundwater” because of the way it is built.) As a consequence, fens typically have a greater diversity of vegetation, which may include more in the way of shrubs and trees.  

In addition to sphagnum moss, the vegetation in a bog consists of heaths (Erica spp.), sedges (Carex spp.) and grasses such as cotton grass (Eriphorum spp.). Bogs also are the home of carnivorous plants such as pitcher plant (Sarracenia purpurea in our region) and sundews (Drosera spp.). These plants have resorted to capturing and dissolving insects for the nitrogen and other nutrients the acidic soils lack. Bogs are also a place where you can find a variety of orchids (Platanthera spp., Spiranthes spp., Cypripedium spp. and several others). Most of these plants are low growing, exotic looking, and can add a beautiful splash of colour to your yard. 

Locating the Bog 

The first steps to building my bog garden, as with all my projects, was to find the most suitable location. I needed an area that I could keep constantly wet. At first I thought I might be able to build it at the outflow from the downspout of my house, similar to a rain garden. But a rain garden is usually designed with plants that can tolerate drying out between rainfall events but won’t easily drown if submerged for short periods. Ideally, a bog garden will stay continuously wet – in fact some bog plants will quickly die if they dry out. I then wondered whether I could use my existing water feature by building a bog at the base of the waterfalls.  

Waterfall Reservoir 

At the base of the falls is a pit approximately 3’ deep and 10’ across, lined with a rubber pond liner and filled with rocks (large ones at the bottom, smaller near the top). A large diameter pipe holds the circulating pump that takes the water up to a small pond at the top where it tumbles back down to the pit. Originally, I had to top up the reservoir at least once a month in the summer because of splash and evaporation, but I have since tied in the downspouts from the house and I now only top it up in prolonged periods of drought. Since this reservoir is almost always full of water, it seemed the perfect spot to put my bog.  

Building the Bog – STAGE 1 

The first thing I needed to do was excavate a hole. Given the substrate consisted of pure river rock, this was not as easy digging as it would have been in soil. But I soon discovered (after a heavy rain brought the water level in the reservoir up to the top) that digging rocks in a flooded area was actually easier than digging them when it was dry. It was just harder to tell how far down I was going.  I just kept digging till the water in the hole seemed to be at least 18” deep throughout. Once I had the hole deep enough, I then placed a rubber pond liner into the new pit and proceeded to poke a number of holes in it with a garden fork. The idea was to allow some exchange of water through the liner rather than rely entirely on rainfall and splash from the falls. (If I were to do it over, I would likely have eliminated the holes in the liner and had a truer “bog”, but I didn’t know if I could keep the soil moist enough with just splash from the waterfalls.) 

Creating the Bog “Soil” 

When you Google bog gardens, you’ll get a wide range of recipes for the soil – anywhere from 75% peat moss/25% sand to an equal mixture of peat moss, sand and local soil. The reason you don’t want a lot of the local soil is that bog plants don’t like a lot of nutrients. I decided on a mix of 50% peat moss (to keep it reasonably acidic), 25% sand and 25% soil (keep in mind that my soil is fairly sandy – if I had clay soils I might have gone with 2/3 peat moss and 1/3 sand – and I had lots of it available). I mixed all this in a wheelbarrow and filled the hole up. I then left it to settle over the winter, figuring I might have to top it up in the spring. In the spring I added another 2” or so of my peatmoss, sand and soil mixture. 

Below are my video record of the construction of the bog garden, and what it looked like the first spring after it was built.

Then Came the Plants 

Deciding which plants to plant was a lot easier than actually finding those plants. In addition to the Purple Pitcher Plant (Sarracenia purpurea) that a friend gave me, I also managed to locate some Showy Lady’s Slipper Orchids (Cypripedium reginae) from an orchid breeder near Toronto, and I purchased and sowed the fine, powder-like seeds of several other orchid species (unfortunately, none of these grew).  

Marsh Fern (Thelypteris palustris) planted around the Showy Lady’s Slippers (Cypripedium reginae) help to keep the orchid roots cool in the full sun bog garden.

But since, like nature and a vacuum, gardeners abhor an empty garden space, I started adding some interesting non-bog plants that liked lots of moisture while I searched for the real things. These included Southern Blue Flag Iris (Iris virginica), Bog Goldenrod (Solidago uliginosa), Ohio Goldenrod (S. ohioensis), Blue Vervain (Verbina hastata), Monkey Flower (Mimulus ringens) and several others. Before I knew it, the bog garden was not only full, but full of large plants that overwhelmed the short bog plants that the garden was built for.  

Next Steps 

Now that the garden has been growing for 3 seasons and proven it works, I now have to do something about all the large plants that are taking over – including a number of volunteers that have seeded in from other gardens, including Joe Pye Weed (Eutrochium spp.), Boneset (Eupatorium perfoliatum), and a couple of asters. To that end, this fall I have started to prepare the ground for a 15’ X 15’ “wetland” that will have its own pond and be home to all these taller wetland species. Then I can get back to growing just my bog plants in the bog garden.  

Conclusions 

Building a bog garden is easy, providing you have a way to keep it moist all year long, and opens up the opportunity to grow some very interesting and unusual plants. Just don’t make my mistake of filling it up with non-bog plants – save those for a wetland or a rain garden.  

From experience, I can tell you that trees and other plants readily seed into the constantly moist soil so you’ll want to make sure you remove them when they are little as they can very quickly develop expansive root systems, making them a challenge to dig out without disturbing the bog plants you want.   

Below are a couple of videos I made in the first summer and in the following spring (if you’re interested in the progress). In the first video, the bog garden tours ends at about the 6 min 36 sec mark – the rest is about my pond and waterfall. The second video shows how things have very quickly started to fill in by the second year.