How to Kill Plants

How to kill plants is something I get asked all the time in the context of “This plant is eating my garden”, or “How do I kill grass in my garden.” So without further ado, here’s the current scoop on killing plants you don’t want in your garden.

1) You can dig them out. Yes, I know it is a lot of work but this is the single best way to clean out a garden. The problem with this is that you have to be quite thorough to get the job done. With many plants, all that is required is a tiny segment of root left in the ground and it will regrow again. So, double digging is a good thing and sorting through every shovel of soil is almost a necessity. How to kill plants? Use patience and perserverance.

This is called garden renovation and if you’re looking at a badly infested garden, then this is what you’ll have to do to eliminate all the weeds (let’s call any plant you don’t want a weed). There is no magic wand you can raise and simply eliminate a bunch of plants without disturbing others. It is slow and it is work but it is effective.

2) You can mulch them out. If you are talking about a large section of ground, then 10 to 15 layers of newspaper laid down on top of the grass or plants will smother them. Wet the newspaper as you lay it down and lay it overlapping so there are no cracks for the plants or grass to escape through. After you have the newspaper laid down, you can put an attractive mulch over top of this.

How to kill plants such as grass? This technique works very effectively to kill grass or large lawn patches so you can plant shrub borders.

This is particularly effective under trees where nothing will grow and you don’t want to water. The newspaper stops the weed and the bark mulch gives you a decorative look.

When you do this, you can grow shrubs and evergreens in this garden space and you might even grow a plant that doesn’t spread or expand (like a vegetable or annual flower) but you wont’ grow too many perennials in this newspaper mulch because they expand from year to year and will have difficulty pushing the newspaper aside as well.

3) How to kill plants with organic sprays. You can use an organic spray such as industrial strength vinegar (acetic acid).This burns off the tops of plants such as dandelions. But it kills anything it touches so do not spray it on good plants. If you spray it on lawn weeds, it will burn off the nearby grass as well.

You will have to vigilant using these organic sprays. The weeds, particularly perennial ones, will have lots of strength in their roots and will throw new top growth within a few short weeks. You have to go after them three or more times in a single season to knock them back to the point where they give up.

How to kill plants with growing conditions. There is a body of research out there that points to some kinds of weeds or plants growing in different conditions and if you change those conditions, you’ll eliminate the weeds. Moss in lawns is a perfect example. Moss thrives in conditions of low fertility. Once you start feeding your lawn and laying down extra grass seed, the moss tends to disappear under the pressure of too much food and competition. (But the complexity arrives at this point when you understand that low fertility is only one of several conditions that encourages moss growth.) Thistles grow in this kind of soil condition, clover in this one. The reality is that it isn’t quite that simple in a mixed garden situation to eliminate one weed and leave another plant thrive. The best we can do for our gardens in a general way is to continue to add compost and compost tea and try to create the best soils we can.

How to kill plants with sprays? You can succumb to the fantasy of chemical sprays Let’s be honest here, there is a fantasy of being able to come onto a bit of ground and “just this once” spray something that will magically remove all weeds and problems. There is a sweet temptation to use it because … well, because it is a lot easier than digging. It is a lot easier than sweating out there.

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I’m not even going to repeat all the data on the Net right now about how the increased rates of Parkinson’s disease in middle aged and seniors is directly related to using chemicals in the house and garden. I’m not going to tell you about the rising rates of ADD, childhood cancers and deformities related to chemical use.

I will simply say that it is wrong to use garden chemicals to save yourself a few steps and a little work when it contributes to the negative health of yourself, your neighbours, your pets and your children. Wreck your environment, your air and your water to kill a small yellow flower on your lawn. Where’s the priorities in life?

End of soapbox – but that's how to kill plants in your garden.

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