This article is NOT about invasive species, but is about the strategies I use to deal with aggressive species in the garden. But first, a note about invasive species. 

Common Reed or Phrag (Phragmites australis), Lily of the Valley (Convallaria majalis), Japanese Knotweed (Reynoutria japonica), Garlic Mustard (Alliaria petiolata), European Buckthorn (Rhamnus cathartica) – these names tend to strike fear (or at least dread) into hearts of native plant gardeners.  They are all invasive species. 

What makes them so bad? All were introduced into gardens from which they then escaped into the wild. There, their ability to spread was so powerful that they soon started to exclude the local plants (and sometime even animals).  

Invasive species may spread by seed (e.g. Garlic Mustard, Phragmites, Buckthorn) or by rhizome (Japanese Knotweed, Lily of the Valley) or both. Control of the spread is difficult, at best.  

Definitions 

In the US, the USDA National Invasive Species Information Center (https://www.invasivespeciesinfo.gov/what-are-invasive-species) defines an invasive species as a species that is: 

1) non-native (or alien) to the ecosystem under consideration and, 

2) whose introduction causes or is likely to cause economic or environmental harm or harm to human health. 

This harm often arises because the plant (in this case) either spreads so prolifically as to exclude all or most other plants, or it uses chemical warfare to eliminate any competition. 

In Canada, the Invasive Species Centre (https://www.invasivespeciescentre.ca/learn/) states that invasive species “kill, crowd out, and devastate native species and their ecosystems”. It goes on to state that  

“A species in considered invasive when: 

1. It is introduced to an ecosystem outside of its native range, and 

2. It has potential impacts on the ecology, the economy, or society in its introduced range.” 

They also point out that in order for a species to become invasive, it must “possess the ability to outcompete and overwhelm native species in its introduced range.” 

Thus, an invasive species is one that is an aggressive spreader. And though we have many native species that are aggressive spreaders – Canada Goldenrod (Solidago canadensis) comes to mind – these plants are not considered invasive because they fail to meet the first criterion of an invasive species – they are not introduced to the ecosystem. They belong here. 

The analogy I like to use is that if a foreign military power attacked one of our cities and did a lot of damage – we would say they had invaded us. But if our own military did the same damage, we wouldn’t say they had invaded (because they belonged here) but that they were, instead, being very aggressive.   

Aggressive Native Plants in the Garden 

Seed Spreaders 

In my southwestern Ontario garden, with its soft, loamy soil, a number of plants behave rather aggressively. Some of these, such as Silphium perfoliatum (Cup Plant) and Rudbeckia laciniata (Green Headed Coneflower), self-seed prolifically. These garden bullies provide great shows in the summer, but tend to outcompete everything else. The only thing I might do to control them is cut off the seed heads before the seeds ripen. Except I don’t do this because I want the seeds to provide winter nourishment for the birds. So instead, I spend a fair bit of energy and time each spring thinning out the excess plants. (These get potted up and planted elsewhere, or are sold to others so I can buy more plants.) 

I have a number of other plants that also self seed prolifically, but they are welcome in the garden because they tend to play nice with others. These include the lovely little Pale Corydalis (Capnoides sempervires), Joe Pye Weed (Eutrochium maculatum), and a couple of milkweeds – Butterfly Milkweed (Asclepias tuberosa) and Swamp Milkweed (A. incarnata). Although they pop up all over the yard, they are not aggressive like Cup Plant so I generally welcome their spread. 

Rhizome Spreaders 

The other way plants spread aggressively in my yard is by rhizome – underground “roots” that pop up plants where you least expect them.  These tend to be the more troublesome group. Some of these plants, like Canada Goldenrod (Solidago canadensis) and Star Flowered Solomon’s Seal (Maianthemum stellatum) can produce such a dense mat of roots that they eventually begin to exclude many of the other plants. These are the real trouble makers. But I have found a way to keep these aggressive spreaders in check. 

Vines and Vine-like Plants 

Not all aggressive plants spread by seed or rhizome. A couple spread by above ground runners, too. Wild Grape (Vitis spp) and Virginia Creeper (Parthenocissus quinquefolia) are two fairly aggressive woody vines that can quickly cover fences or trees if allowed to spread. Fortunately, an quick annual pruning is all that’s needed to keep them in check. 

A perennial, vine-like plant that likes to take over garden spaces is the lovely Virgin’s Bower Clematis (Clematis virginiana). It seems that every leaf-node that touches the ground on this rapid growing and sprawling plant wants to set down roots and sprout a new plant, which then sends out its own runners (stolons) which do the same. My Clematis grows along the fence that bounds one of my flower beds. Each spring I have to follow the runners throughout the flowerbed and pull up dozens and dozens of plants. Fortunately, these are readily potted up for resale so I can buy even more plants (or to give away if you’re not as mercenary about it as I am).  

Controlling the clematis is a challenge in my garden because I like the look of it sprawling along the fence. If I wanted to keep it under better control, I would simply plant it in front of a trellis and prune it to stay there. 

Controlling the Spread of Rhizomes – Root Barriers 

My first root barrier was for Purple Flowering Raspberry (Rubus odorata). I was warned that these shallow rooted shrubs send out a lot of rhizomes, so I purchased a length of aluminum from a company that makes eavestrough. (They were installing new eavestrough on the house across the street so I just went over and asked if I could buy some.) This allowed me to “fence off” a large area.  

It took many years before the leaf litter and wood chips got deep enough to allow the roots to go over the barrier. A little maintenance once every few years would have prevented this, but where it was growing I wasn’t too worried about it. And it’s definitely an easy fix if I decide to bring it back under control. 

In order to keep plants more contained, I now grow all my aggressive spreaders in a large pot in the ground – in my case I use half of a plastic 45 gallon barrel, sunk into the garden. The barrels are cheap – you can usually pick up one for $10-20 (which gives you two pots). Sometimes you can even find them for free as I did when I volunteered to help clean up the river bank with our local conservation authority.  

After cutting the barrel in two, I then drill some 1” holes in the bottom for drainage. I dig out a hole deep enough so that only about 1” of the barrel is above the ground, set the barrel in, then put the soil back in. (This is a great opportunity to amend your garden soil if, for instance, you are putting in an acid soil loving shrub, of if your soil is heavy clay and your plant wants a sandy loam, etc.) 

I planted my Jerusalem artichokes in a half barrel 5 years ago. It has never escaped. And each fall I simply harvest as many of the tubers as I find – I always miss a few tiny ones – and the next year these missed pieces become a new crop. 

If digging a 3’ by 3’ hole in your yard is more than you can handle, I have successfully grown Common Milkweed and Grass-leaved Goldenrod in a large plastic pot – the kind small trees often come in. They’re only about 12-16” tall and a foot across. The plants grew in them for years. 

A List of Troublemakers 

The list below is by no means comprehensive, but it includes those that are the worst offenders in my garden for spreading by rhizomes. These are plants that need a lot of room to spread and may not be suitable for smaller garden spaces unless their control is kept in check with some form of root barrier.  (Listed in alphabetical order by scientific name.) 

Canada Anemone (Anemonastrum canadense) 

Common Milkweed (Asclepias syriaca) 

Virgin’s Bower Clematis (Clematis virginiana) 

Grass-leaved Goldenrod (Eurybia divaricata) 

Jerusalem Artichoke (Helianthus tuberosus) 

Star Flowered Solomon’s Seal (Maianthemum stellatum) 

Obedient Plant (Physostegia virginiana) 

Prickly Gooseberry (Ribes cynosbati) 

Smooth Wild Rose (Rosa alba) 

Purple Flowering Raspberry (Rubus odorata) 

Canada Goldenrod (Solidago Canadensis)  

Prickly Ash (Zanthoxylum americanum) 

You CAN grow many of these aggressive plants in a small space without them getting out of hand. I hope these suggestions help you grow some of the lovely native plants we have that you haven’t grown before because of their aggressive nature. 

Happy Native Plant Gardening. 

March 1, 2024 is an exciting date for me. This is the release date of my book The Gardener’s Guide to Native Plants of the Southern Great Lakes Region. I thought that for this month’s article I would share a bit of what it took to get this book to publication. 

The Original Idea 

I started growing native plants in my yard around 2006. As with many native plant gardeners I’ve met, the process got off to a slow start. I knew nothing about our native species and, as many do, I soon learned that “wildflower” was not the same as “native” and that many of our wildflowers were actually garden escapes of European origin. What I really needed was a book to help me figure it all out.  

One of my first books was Lorraine Johnson’s fabulous 100 Easy to Grow Native Plants for Canadian Gardens (Whitecap Books, 2005). With lovely photos and vital statistics about each plant, it was a fantastic jumping off point on my journey. I soon found, though, that many of the plants in my little book weren’t actually native to where I live, so I started buying more books on the subject. (I now have over 20 feet of bookshelf space dedicated to nature – most of which are directly or indirectly related to native plants and native plant gardening!) 

The more I read, the more frustrated I became that I couldn’t find everything I needed in a single volume. Some books provided great growing information, some had wonderful photos of flowers, some had images of the seedhead and leaf, others had great anecdotal information about the ecology of the plants, but none seemed to have it all. And only one (Gisèle Lamoureux’s Flore printanièr [Spring Flora] – published by Fleurbec in Quebec and written in French) provided any kind of native range maps. I wanted to know if the plants I was about to add to my garden were actually NATIVE to my area, not just somewhere in my province.  

The Inspiration 

Then, around 2015, I bought a copy of Manitoba Butterflies: A Field Guide (I was living in Manitoba at the time) by Simone Hebert Allard and published by Turnstone Press (you can read my review of the book at https://www.amazon.ca/gp/customer-reviews/R39JQA3T4VPF1Y?ref=pf_ov_at_pdctrvw_srp). That’s when the lightbulb came on. This was the format that a book for native plant gardeners needed to have. A two-page spread for each plant, photos of the plants showing the leaf, the seedhead, the flower, and of the whole plant (ideally in a garden setting). But, critically, it also should have a detailed map of WHERE the plant was native. After all, native plant gardeners want to know if the plant they are growing is actually native to where they live.  

Research, Research, Research 

When I started putting together the book, I started by simply using the spreadsheet I had created that listed all the plants I was growing in my own garden. By that time, I had over 200 species of native and near-native plants. I created a file folder for each plant and then systematically began putting everything I could find into each plant’s respective folder. This included photos, maps, scientific journal articles, and a page of links to various websites.  

I then created a template of the information I thought was needed in such a book. I started to sift through the thousands of documents I had and fill in the blanks in each plant’s template page. This template grew as I added more sections, then shrunk again as I removed some which, for various reasons, we decided to leave out (edibility and medicinal uses, for example, were two we eventually removed). 

Collaboration 

I spent about 3-4 years working on this project in my spare time. By this point, I had a mostly complete template page for about 230 species. I had no problem filling in the blanks for each plant from my research – information like plant height and width; flower colour; soil, sun and moisture needs; propagation; and so on. I realized that the book also needed a description of the plant to help people with more detail than you might see in a photo, and a description of the plant in the garden. But by this time I was running out of enthusiasm. It had been a solo effort that consumed almost all of my free time, often working late into the nights. 

That’s when I was inspired by an article I read by Shaun Booth. Shaun ran In Our Nature, a native plant nursery and ecological garden design and construction business in southern Ontario. He also launched the Ontario Native Plant Gardening group on Facebook (which now has close to 25,000 followers). I asked Shaun if he would be interested in writing up the plant description parts and he said yes.  

Bringing Shaun into the project launched a 2 year partnership that rekindled my enthusiasm for the project. It gave me someone knowledgeable to bounce ideas off of and, like me, Shaun believed the book was necessary. 

Getting the Picture 

Both Shaun and I have been photographing flowers in our gardens and in the wild for many years. But it soon became apparent that if we were going to use our own imagery in the book, we were going to need a lot more pictures than what we had (and, believe me, we had LOTS!).  

We quickly realized that we both photographed primarily the flowers. We were missing examples of the leaf and seedheads and of the whole plant in the garden for many species, and that meant we had to go back to the start and make a list of what we were missing then try to get those shots.  

While we pursued a publishing contract, we spent a lot of time getting those images. But just in case we couldn’t get good photos, we also started to approach folks who had posted the images we needed on iNaturalist and other sites. And almost every single person we approached agreed to let us use their image. Many didn’t even want the photo credit (but if we used their photo, we certainly gave credit). In the end, we managed to take most of our own pictures, and I want to acknowledge our heartfelt gratitude to all those who offered up their images. 

Making the Maps 

Mapping the native ranges for the plants was a whole other adventure. Fortunately, my background is in Geographic Information Systems (GIS) and making maps is what I did for many years. However, as I say in the introduction in the book: 

“The maps in this book have been generated using all the information we could find online and through scientific journals and other publications. Some species, such as the goldenrods and asters, have been studied extensively in Ontario and elsewhere, and their native range is reasonably well documented. For many plants, however, there is little information available at an appropriate scale. In some cases, multiple sources provided similar ranges, which made mapping easy. However, in a few cases the range maps were so different that I wondered if they were even talking about the same species.” 

Fortunately, we also had the fantastic support of ecologists and state botanists who graciously looked over the maps and pointed out any egregious misinterpretations we might have made. The result is that the book contains a map for each plant that shows its approximate native range in the southern Great Lakes region. 

Finding a Publisher 

Finally, we were ready to publish. That process was a long and challenging one. In Canada, the process for getting a non-fiction book published is very different than for publishing a novel. The industry standard is to produce a multi-page proposal that outlines what the book is about, provides examples of the content, compares it to books already on the market (the competition) and explains why your new book is needed. It requires references, ideally from other authors (which means they must read it first), and then you must show the publisher how you are going to help them promote and get sales for your book.  

In our case, we sent proposals to half a dozen publishers over the period of a year (in North America, publishers, more often than not, don’t even respond if they’re not interested, and if they do it can be months later before you hear from them).  

Finally, in frustration, I put together a mock up of what I envisioned the plant pages would look like and posted to various native plant gardening groups on Facebook, asking if something like this would be of interest. I was overwhelmed with the response. In 3 days, over 600 people got back to me saying they would definitely buy the book – in some cases saying they wanted multiple copies.  

One person who saw my post, Carol Pasternak, already had a book published by Firefly Books and asked if I wanted her to show the concept to her publisher. I did, so she did, and the publisher liked what they saw, and within a week we had a contract offer. 

Once the contract gets signed, you work with an editor to polish the book. The editor I worked with at Firefly was amazing. I found the process informative, extremely helpful, and working with Julie (my editor) was a wonderful experience. We had a couple of “creative differences” during the process, but were able to quickly come to a satisfactory compromise. The result is a book that looks great and that I hope gardeners will find to be extremely useful.  

Some images from the book:

Next Steps 

By the time you read this, the book should be available at bookstores and through online sellers. The book covers 150 plants but, if you remember, at the beginning I said I had about 230 species on my list. I was informed, and rightly so, that 230 plants (at 2 pages per plant) would make a volume that was large and unwieldy and very costly to produce (and therefore expensive to buy).  That means that I’ve already got close to 100 plants ready to go for a volume 2, if demand warrants.  Hopefully you’ll find this book to be a valuable addition to your library.  

I will soon be on the road promoting the book at speaking engagements and doing book signings throughout the region – my calendar is already beginning to fill up. But I am proud of the new book. It’s the book I wish I had when I started gardening with native plants. 

Happy Native Plant Gardening! 

They don’t have big showy flowers (or even tiny inconspicuous flowers), they don’t feed pollinators or even rabbits (usually), and only a few seem to be host to some moth caterpillars, but it is my firm belief that every native plant garden should have ferns.  

There are native ferns for just about every garden condition in the Southern Great Lakes region. After all, according to the Peterson Field Guide to Ferns of Northeastern and Central North America, “some 11,000 different species of ferns and fern relatives… occupy every corner of Earth, from mountaintops to deserts to coastal swamps.” That book covers over 100 species that are mostly native to our region. There WILL be a fern that will grow in your garden. 

In this month’s article I will take a look at some of the ferns I have in my own garden in southwestern Ontario (as well as a couple I don’t have) and I will discuss why I like them. I have at least 18 species of ferns in my gardens – I have had more in the past, but lost a few over the last couple of years due to changing conditions in my yard. 

My Top 10 Ferns 

The following ferns are ones that just about anyone can grow in their gardens. They tolerate a wide range of soil moisture and/or light requirements and are long lived. (The plants are listed alphabetically by scientific name.) 

Maidenhair Fern (Adiantum pedatum) – If you have a moist, humusy, full-shade garden, there are few ferns that add as much delicate beauty as the clump forming Maidenhair Fern. Also known as the Northern Maidenhair Fern, the Five Fingered Maidenhair Fern or simply the Five Fingered Fern, these ferns will tolerate some sun, providing they are kept moist. 

This deciduous fern has black, shiny stems that reach up from a creeping rootstock to form a horseshoe-shaped semi-circle of horizontal bright green fronds. Maidenhair Ferns can get up to 3’ tall, but more commonly tops out around 18-24”. This is, apparently, one of the most sought-after native ferns at garden centres, and for good reason. An excellent choice for a full shade rain garden or bog garden, it regularly gets oohs and aahs from visitors to my yard. My only wish is that it would spread a little more aggressively – it seems to take forever. 

Lady Fern (Athyrium filix-femina) – A gorgeous 2-3’ tall fern that gets as wide as it is tall, Lady ferns provide a delicate lacy look to the flower bed. This fern prefers dappled shade and moist to mesic conditions in any loose loamy soil, but will tolerate a fair amount of morning sun and I have seen it growing in full shade in forests.  

I have a robust specimen that anchors the corner in a shady garden. Small offsets form at the base, allowing this fern to spread – albeit VERY slowly. My specimen is close to 15 years old and is less than 2’ across at the base, but its full bushy nature makes it look much larger.  

Bulblet Fern (Crystopteris bulbifera) – If I had to pick just one fern to grow in my garden, it would be this one.  In early spring, the bright red stalks are very showy. The fronds will get quite long (up to 30”), but they tend to flop over and, in my garden at least, seldom get higher than 12-18”. They do work well in planters, though, providing a lovely cascading effect.  

The plant gets its name from the tiny “bulblets” that grow on the underside of the fronds (in addition to the typical sori – groups of spores – that are found in ferns). These bulblets fall to the ground where, if the conditions are suitable, a new fern will spring up. 

Bulblet Ferns – which have a number of common names including Bulblet Bladder Fern, Bulblet Fragile Fern, and Berry Bladder Fern – are a garden winner in many regards. In a low, moist area of my yard, these tiny ferns grow in full sun and maintain a reddish brown tinge throughout the summer. But I also have them growing in full shade in an old claw-foot bathtub, where I never water them and even in the driest years they have stayed green and fresh looking all summer long.   

Crested Wood Fern (Dryopteris cristata) – New in my garden this past year, I’m loving the delicate look of this little (1-2’) clumping fern. It prefers part to full shade, but will even grow in full sun if sufficiently moist. It spreads slowly by short creeping rhizomes and, given sufficient time, can produce a nice, dense groundcover. 

This fern is considered semi-evergreen as the fertile fronds tend to collapse during the winter, but the sterile fronds remain green all winter long. Also known as Buckler Fern, Crested Shield Fern, or Narrow Swamp Fern, this is a good choice for loam to clay soils.  

Ostrich Fern (Matteuccia struthiopteris) – At up to 4’ tall when mature, this fern is super easy to grow in clay to sandy loam, full shade to mostly sun (with sufficient moisture) – though dappled shade is best – and dry to seasonally wet soil. In very dry soils, such as under a Sugar Maple tree, it may go dormant partway through the summer. It tolerates flooding in the spring so is ideal for that low spot where the snow meltwater collects.   

It is a slow but persistent spreader and may not be suitable for small gardens. Ideal companion plants are Virginia Bluebells (Mertensia virginica), Trilliums, and Bloodroot (Sanguinaria canadensis), all of which bloom then begin to fade away just as the Ostrich Fern begins to fill out. Oh, and the unopened fronds are the edible fiddleheads you can find in specialty grocers in the spring. 

For me, a key identifying feature is the badminton shuttlecock (“birdie”) form of the plant.  

Sensitive Fern (Onoclea sensibilis) – Sensitive Ferns are not particularly drought tolerant but they will do OK in average garden soils as long as they aren’t allowed to get too dry. They do prefer consistent moisture. Their strength, though, is that they tolerate full shade to full sun, though they may turn yellow without a bit of protection from the afternoon sun. In my garden, these ferns rarely get taller than 2-3’, though the literature suggests they will get up to 4’ tall. They tolerate most soil types, from sandy loam to clay. 

They will form dense colonies but don’t spread as quickly as Ostrich Ferns and make a great ground cover in moist, partly shaded areas. Their woody-like fertile fronds persist through the winter and provide interest in the garden year-round. They get the moniker “Sensitive” because they are very sensitive to frost. 

Royal Fern (Osmunda spectabilis formerly O. regalis, the latter name now reserved for the European species) – Royal fern is one of the tallest ferns we have, reaching up to 6’ in rich, moist to wet soils in full to part shade. It can even take periods of standing water.  It very wet conditions, it will even tolerate full sun.  

I’ve been growing this in less than ideal conditions for the past 5 years and my plants rarely get over 3’ tall, but this past summer I built a mini artificial wetland and moved some to that area. I’m hoping it will take off next year in its new home. 

The leaflets of Royal Fern look a bit like a locust tree or a vetch, and its size makes it more shrub-like than what we typically think of a fern. Fronds typically turn yellow to brown in autumn. Spores are located in brown, tassel-like, fertile clusters at the tips of the fronds, thus giving rise to the additional common name of flowering fern for this plant. Osmunda fiber used in the potting of orchids comes from the fibrous roots of these ferns. 

Smooth Cliffbrake (Pellaea glabella) – Difficult to find, and very fussy about its growing conditions, but if you have large limestone rocks in a lightly shaded area (or full sun, if moist), these tough little ferns are worth seeking out. They are a very small fern, only getting from 1” to 15” tall, but they will grow out of seemingly soil-less rock so they don’t have to worry about competition.  

They are found on limestone cliffs in full sun to part shade. In appropriate conditions, this hardy little fern is evergreen, but here in my southwestern Ontario garden, growing on a dry “escarpment”, it turns brown and looks completely dead in the winter – though the fronds remain. With the first mild wet weather, the fern perks right back up and turns green again. The same thing happens during a summer drought. More than once I was sure the fern was dead, and then a nice rainy day brings it right back to life. It is an extremely slow grower. 

A close cousin, Purple Cliffbrake (Pellaea atropurpurea), can be differentiated as it has a hairy stem instead of a smooth one. It is also much rarer (considered vulnerable in Ontario and imperiled in Michigan). 

Christmas Fern (Polystichum acrostichoides) – This long-lived (15 years, or more), medium sized fern (18-24”) is one of only a handful of native ferns that is evergreen – retaining its shiny green leaves right through to the spring. They do flatten down in the winter, but still provide shelter for small birds and mammals, and nesting materials in the spring.  

A forest floor inhabitant, it prefers moist, full shade, but will tolerate dappled sunlight if kept moist. They don’t do well in heavy clay soils, but they don’t mind pretty much any other soils, including average garden soil where a weekly watering will keep them green and healthy. Once established, they will tolerate periods of drought and would make a good filler plant in a shady rain garden. 

Easily recognizable in the winter (because it’s evergreen), a simple way to recognize Christmas Fern in the summer is the “thumb” on the individual leaflet (see image below). 

Marsh Fern (Thelypteris palustris) – This low growing (6-12”), sun loving fern is great in a bog garden, a rain garden, or any other place where it can be kept moist (though it doesn’t like standing water). The delicate leaves can form dense mats, which help to provide necessary cool shade for the roots of things like Showy Lady’s Slipper orchids (Cypripedium reginae). This fern prefers rich, acidic, sandy loam but will survive in just about any garden soil, as long as it is moist. For a fern that is so delicate looking, it really is a tough plant. Other names for this fern are Marsh Shield Fern, Northern Marsh Fern and Eastern Marsh Fern.  

It is very similar to New York Fern (formerly Thelypteris noveboracensis, now known as Amauropelta noveboracensis), which can tolerate a bit drier conditions and would make a good substitute. Keep in mind, though, that New York Fern can become a dominant understory species and may out-compete the seedlings of certain tree species. The seedlings of Wild Black Cherry (Prunus serotina) are especially vulnerable, as the fern releases an allelopathic phenol which can kill them. 

Honorable Mention 

Cinnamon Fern (Osmunda cinnamomea) – Cinnamon Fern has gorgeous fall colour, prefers part to full shade and will tolerate full sun if it is in standing water. It will grow in most soil types, including muck, and can get almost as tall as its cousin, the Royal Fern. This is a great pond or bog plant. 

I don’t include it in my top ten ferns simply because I have not had great success keeping it alive. I’m on my third attempt to grow Cinnamon Fern and I may have to move it to a wetter area than where I have it now. But it is quite gorgeous – especially in the fall.  

Ferns for More Experienced Gardeners 

The ferns in this section really aren’t for beginners. That’s because they are a little fussier on their growing conditions, and/or they are very aggressive spreaders. But if you have the space and/or the appropriate conditions and/or the experience and want to try something interesting, these are, in my opinion, some lovely ferns to add.  

Hay Scented Fern (Sitobolium punctilobulum) – A beautiful fern for large areas, it is an aggressive spreader that gets 1-3’ tall and gives off a scent of crushed hay in late summer.. Prefers light shade and moist to mesic soils but will grow in a wide range of conditions. 

Bracken Fern (Pteridium aquilinum) – Full to part sun, drought tolerant once established, this very aggressive spreader is not suitable for small spaces. However, it is so tough that I have read that it will actually thrive in the dry shade under sugar maples (but I haven’t tried it – yet). As I’ve seen it growing along roadsides in sandy soils, it might make a good plant for a Hell Strip (boulevard) garden. It gets up to 4’ tall. 

Hart’s Tongue Fern (Asplenium scolopendrium) – I’ve tried to grow this rare (it is classified as “vulnerable” in Ontario), very unusual looking fern twice, in two different locations, but couldn’t keep it alive past the first year. A friend, however, has it growing beautifully in his yard. It wants part to full shade in rich, moist but well drained soil.  

Maidenhair Spleenwort (Asplenium trichomanes) – This extremely delicate looking fern grows in full to part shade in rich, moist, well drained soils, and rocky terrain. I’ve seen it growing in crevices in limestone alvars with virtually no soil at all. It is small, about 6” tall, and is evergreen.