Last month I wrote about preparing your lawn for a new garden. In that article I discussed some of the strategies I’ve tried (and a few I haven’t) for removing the sod. This month I’m going to look at a few techniques for making your garden edges look more formal so that your lawn doesn’t look like it’s simply being neglected. This is partly because on social media there have been a number of postings recently about “tidy” gardens (and the issues that arise when neighbours think your garden isn’t tidy enough). I have used most of these techniques or have friends who have used them. Hopefully this month’s article will give you some useful ideas to try. 

In the Beginning 

In my early gardening days with native plants, I had a couple of relatively small flower beds. Using plastic garden edging was both affordable and easy. The nice thing about the plastic edging is that it provides a nice, clean edge with virtually no maintenance after it’s installed.  

But all plastic edging is not created equal. The small (usually 3-4”) lightweight stuff is, in my opinion, a waste of money as it will work out of the soil with frost heave in only a couple of years. Go for the heavy duty stuff – 5” or more – and you should be good for years to come.  

But even the heavy stuff has issues. I find that on sharp curves the plastic will work up out of the soil. And it doesn’t take much to catch it with the lawnmower and then you have a shredded piece of edging. It also doesn’t work that well if you have any kind of topographic variation to your lawn. It may snake around curves nicely, but it definitely doesn’t handle the up and down curves of the ground.  

Dig a Trench 

Almost all my flowerbeds over the last 10 years have had no hard edging at all. Instead, I dig a V-shaped trench (about 3-4” deep) around the perimeter of the garden. In my sandy loam soil, this is a pretty easy trench to dig. 

One of the big advantages of this is that as your garden expands (as mine invariably do), I simply dig the perimeter trench a little further out. Another advantage is that topography makes little difference – your trench simply follows the lay of the land. 

Unlike plastic edging, however, the v-trench requires annual maintenance (at best). Grass grows in, seeds fall into the trench and sprout, soil gets trampled, and before you know it there is little evidence of a clean edge. To me, though, the little time it takes to re-dig the trench is worth it for the flexibility it offers.  

Another drawback to the v-trench edge is that you can’t really get the lawnmower close enough to trim the grass – unless there is room in the bed itself to run the lawnmower wheels (usually ok for the first year or two, but eventually my flowers push right to the edge of the garden). As a consequence, I have to take the grass trimmer to all my beds that are trenched. This is just one more chore to add to the gardening tasks. 

Fill in the Trench 

A technique I was introduced to this year definitely warrants some further investigation by me as it seems to provide the best of both methods.  

A good friend digs a U shaped trench about 4-6” wide and just as deep along the edge of her gardens then proceeds to fill the trench with limestone screenings. She then packs the screenings in with a tamper.  

Not only does this make a clean edge to the flower bed, but it also provides a smooth surface to run the lawnmower wheel along.  Weeds like Creeping Charlie will grow over it, but very few roots will actually penetrate the stone screenings – which is great for things like twitch (quack) grass. If you want to keep plants IN the bed, too, you can always dig the trench a little deeper and even your goldenrods won’t escape. 

Another advantage is that, like the v-trench, topography of your lawn won’t matter.  

The only drawbacks that I’ve noticed so far is that some weed seeds will grow (mostly lawn grasses) in the stone dust, but these do pull out easily if tackled early. Another challenge is that the edge is semi-permanent – it will be a bit of a job if you need to move the border, though a sharp shovel after a good rain would do the job easily enough. 

Make it Permanent 

A couple of other options would be to make the edging out of poured cement instead of stone screenings. NOTHING will grow through it and there will be no maintenance for many years. Of course, don’t expect to move the border any time soon. 

Rather than pouring concrete, you could also dig your trench and lay in concrete blocks or bricks. These can make a clean edge while being a lot easier to move if needed.  

The friend who uses the limestone screenings plans to try using “universal curb” blocks for the straight-line edge of a couple of her beds this fall. These concrete blocks are 3” wide X 8” deep X 39” long and apparently weigh just over 85 lbs each. And they aren’t cheap. We’ll see if they work as expected. 

Make it for Show 

Of course, your garden edging can be mostly for show. In other words, you can install some low cost, low profile fencing along the edge to make your garden “deliberate”, even if the bed is a tad messy. I’m a huge proponent of the lazy gardening method and prefer not to clean up stalks and leaves till late spring when most of the insects are out of their winter homes. For that reason, anything that helps to give the appearance that the garden mess is purposeful (and not just neglect) is worth a try. 

Fences come in all sizes, colours and configurations and there’s probably one for every budget. But if this is for a front yard, make sure that your fence doesn’t obstruct sightlines or violate any municipal bylaws. 

Happy native plant gardening. 

Most people reading this article will have, at one time or another, faced the prospect of removing a section of lawn in order to create a new garden – whether that be specifically for a native flower bed, for a vegetable patch, or for some other good reason. Today I want to discuss some of the pros and cons of the various methods of getting rid of the grass that I have experienced in my quest to grow something besides lawn. In particular I will look at the following 5 methods… 

1. Herbicides 

2. The “Lasagna” Method 

3. Tarp 

4. Solarization 

5. Removing the Sod (with shovel or mechanical sod lifter) 

Herbicide (Glyphosate) 

Let me start this section with the confession that, in the early days of gardening, I DID use RoundUp (i.e. Glyphosate) to kill off the sod, but I no longer use this method (see *Note at the end of this article on my feelings about Glyphosate).  

Roundup is very effective at killing sod. It is also very easy. The best part of it is that it is relatively quick – spray your patch of grass this weekend, and next weekend start lifting the dead sod (it can take up to 2 weeks for some of the plants to turn brown, but they will be dead. Glyphosate is drawn down into the roots of the plant via the sap stream in the leaves, where it prevents the roots from absorbing nutrients from the soil. The big advantage is that if you don’t dig out all the roots, it won’t matter.) 

However, RoundUp is expensive, hard to get (in some cases), and carries a huge stigma. It also has the distinct disadvantage of potentially killing off good plants through spray drift. Another drawback is that if you accidentally step on a sprayed patch, you leave footprints of dead grass across your lawn as you walk back to the house. (Ask me how I know this – d’oh!) That makes it pretty obvious that you have used Glyphosate to anyone who visits (at least until the dead spots fill back in). 

And, although the sod is now dead, you still have to rototill it up or dig it out before you can plant your new garden. I would only recommend this method if your patch of lawn is heavily infested with bindweed or some other equally deep-rooted invasive species that you won’t be able to easily remove with the other techniques. 

The Lasagna Method 

The lasagna method of gardening is often used in the preparation of vegetable gardens. This is because the materials used will create a rich, moisture retentive garden soil that may be too rich for native plants. However, if you are developing a garden in a new subdivision where all the topsoil has been removed, or on land that was once a gravel pit, this method might work for you. 

The trick with the lasagna method is to lay down a layer of cardboard or newspaper first. This helps to smother the grass (these materials will decompose in a year or less and become part of the soil). You then cover it with layers (like a lasagna) of mulch, lawn clippings, compost, etc. to make a rich, fluffy soil to plant into. The process can take a year for the layers to break down enough to become soil, so it is a long term process. 

A great advantage to this method is that you don’t have to physically remove the sod. And you can plant right into the decaying mulch. (Don’t do this if the mulch is actively working and is hot – you could burn off the sensitive plant roots.) 

The big disadvantage is that it can take the better part of the year to decompose enough to safely plant into – depending on weather, depth of mulch, etc. 

Tarps, Old Carpet or Cardboard 

Similar to the lasagna method, in that this method starves the sod (and weeds) of light and moisture, a tried and true way to kill grass is to cover it with some form of dark barrier. The main drawback to this method, if you’re an impatient gardener, is that it can take months to ensure the grass and weeds are all killed.  

Cardboard will work, though it might be a tad of a challenge to keep it from blowing around or getting shifted from foot traffic. Adding some mulch to weigh it down brings you back to the lasagna method but, if your land is stony, you could use rocks to keep it in place. Cardboard will eventually deteriorate, and if you don’t plan to leave it in place and plant through it (cutting holes for each plant), then it can be pretty messy to lift for disposal. 

I have used old carpet – someone had put rolls of it out for garbage pick up and I just scooped it up and took it home. If there is a carpet store near you, they will likely be glad to give you carpet they’ve ripped out of someone’s house – it will save them from taking it to the dump. The carpet was quite effective at killing off the grass under a large maple tree and it did not have to be weighed down with anything as it was quite heavy enough to resist any unwanted movement – especially after it had been rained on. The hard part was cutting up the old, smelly, rotting carpet to dispose of it – small chunks at a time – with my household garbage once it had done its job.  

Tarps work well. They have the advantage of being lightweight and easy to handle, and they come in various sizes (and colours). They do need to be weighted down (with stones or bricks) or pegged. The drawback is that they are pricey and UV rays will eventually break down the plastic if it is left in full sun for the better part of a year.  

A much more frugal option is to go to your local lumber yard and ask for the plastic tarps that cover the lumber piles. These are normally just thrown in the garbage when a new shipment of lumber comes in. My local lumber yard chuckled when I asked if I could have a couple, but they gave them to me for free. If you’re lucky, you may get some that don’t even have rips or holes in them. And the bonus: you can cut them to fit any shape garden without worrying about ruining a perfectly good tarp. 

Like other methods of smothering the grass, you will probably have to leave the covering on the lawn for several months to effectively kill unwanted weeds. Some of the very persistent plants (like bindweed, etc) may even survive tarping – especially if they are well established in your lawn. 

Solarizing 

Solarizing is similar to the tarp method, but with the use of clear plastic sheets that magnify the sun’s rays to kill the grass. Proponents claim this can effectively kill off the sod in a couple of months. It is a method I have NOT tried, so I only have their word for it. Nor do I know how effective it is on those deep rooted weeds like bindweed. But if your future garden area is small, you can buy clear plastic (sold as vapour barrier in the hardware store) at a relatively reasonable price. 

Shovel, Mechanical Sod Lifter 

My preferred method of sod removal these days is a flat-bladed shovel. This is because I enjoy the physical aspect of digging, I have a flat-blade shovel (so it doesn’t cost me anything), and my soil is a nice sandy loam that is easy to dig.  

With my shovel, I simply dig a small v-shaped trench around the perimeter of the new garden bed, then shove the blade under the grass and flip it up. I then toss the sod clump into the wheelbarrow to be dumped (grass side down) in a back corner of the yard where the grass then dies – leaving a pile of topsoil for use when and where I need it. The drawback is that this is a slow process and can be very hard on the back. The good part is that you can dig out any deep roots as you come across them.  

I’ve never tried an actual sod lifter, either a manual one a powered one, but really these are just more sophisticated versions of the flat shovel.  You can usually rent manual lifters or powered sod lifters, depending on your budget and the size of the garden area, at most of your typical tool rental places. 

The End Results 

Ideally your efforts will result in a garden that is free of grass and weeds, ready to plant into. You may have to rototill if you are in heavy clay soil or you may do like I did and simply add a layer of woodchip mulch to keep moisture and soil organisms in place, thereby letting nature loosen the soil for you. In the end, you should have a wonderful new garden bed that is ready to go. 

Happy Native Plant Gardening. 

PS – My Thoughts on Herbicide Use (this may be controversial for some!) 

*Note – I do not have a problem with the judicious use of Glyphosate, in small amounts, for very specific plants – especially for invasive, poisonous or extremely deeply rooted plants (like bindweed). Round up is broken down in the soil by soil bacteria within a few days. The bacteria use it as a food source (Kanissary, et al., 2019). “Glyphosate’s half-life in surface waters after forestry spraying in Manitoba was less than 24 hours. In soils, glyphosate undergoes microbial degradation to the metabolite aminomethylphosphonic acid (AMPA), which is slowly degraded to carbon dioxide and simple inorganic compounds” (Gov’t of Canada, 2015). 

For those who believe salt, vinegar and dish soap are a better option, I suggest you do some unbiased research. That home remedy will kill off the above-ground part of the vegetation only (it is a contact herbicide and works by killing whatever it comes in contact with), but not the roots, so most perennials will just re-grow. In the meantime, you will have poisoned the soil for microbes, earthworms, etc., killing off those important soil fauna (Enroth, 2020). If you believe that this is a chemical free way to kill plants, remember that salt is the chemical sodium chloride and vinegar is acetic acid, and in sufficient quantities to burn off plants, these chemicals will also kill soil micro- and macrofauna. Research has also shown that acetic acid in great enough concentration to effectively kill plants (5-10%) is “incredibly harmful to humans. Any contact with the skin and eyes causes irreversible corrosion and damage, meaning gloves and goggles are a must when using vinegar herbicides” (Enroth, 2020). In fact, even at these high concentrations of acetic acid it is really only effective at killing very young (less than 2 week old) seedlings and some young annual species (Smitth-Feola & Gill, 2022). 

Equally as problematic, it will kill any frogs or toads it happens to land on (Enroth, 2020). For herbicides to be approved in the first place, they have to be shown to target only plants, usually by attacking specific plant parts at the cellular level, like the chloroplast which animals and other organisms lack. Neither salt nor vinegar are approved as herbicides because they impact both plants and animals that they come into contact with (Pelliccia, 2024). A good friend accidentally spritzed a toad while using the concoction. She noticed right away and washed the toad off, but it died anyway.  

I am not condoning the wholesale use of herbicides to remove lawn. Quite the contrary. But if it is used carefully and in small quantities, it can be a very safe and effective solution for problematic weeds. 

References 

Enroth, C. 2020. Home Horticultural Remedies. University of Illinois Urbana-Champaign, Illinois Extension. https://extension.illinois.edu/blogs/good-growing/2020-05-22-home-horticultural-remedies  

Government of Canada. 2015. Guidelines for Canadian Drinking Water Quality: Guideline Technical Document – Glyphosate. https://www.canada.ca/en/health-canada/services/publications/healthy-living/guidelines-canadian-drinking-water-quality-guideline-technical-document-glyphosate.html  

Kanissery, R, Gairhe, B, Kadyampakeni, D, Batuman, O and Alferez, F. 2019. Glyphosate: Its Environmental Persistence and Impact on Crop Health and Nutrition. Plants. doi: 10.3390/plants8110499 

Pellicia, S. 2024. Salt & Vinegar on Weeds? Save it for the Chips! Washington State University/Washington Dept of Natural Resources. https://foreststewardshipnotes.wordpress.com/2024/06/12/salt-vinegar-on-weeds-save-it-for-the-chips/  

Smith-Feola, D. and Gill, S. 2022. Vinegar: An Alternative to Glyphosate? University of Maryland Extension, https://extension.umd.edu/resource/vinegar-alternative-glyphosate/