Search

Winning the War on Weeds

Updated: Jul 7

We’ve fought our share of weed battles over the years having grown on 10 different plots, most of which started with serious weed problems. We’ve used a variety of strategies to combat weed pressure over the years and have finally arrived at a place of comfort with our current level of weeds. They pop up here and there, but the days of overwhelm are long gone.



Today, I regularly get comments from people walking by our gardens about how amazing it is that we don’t have any weeds. This is actually a misconception, because there are still weeds and there always will be. People just don’t see the weeds since I pull them out long before they are capable of competing with our vegetables. They also catch me in the act of weeding much anymore because that work is pretty quick these days.


The essentials of our weed management strategy can be narrowed down to 3 principles. Let’s call them the 3R’s of weed management. When you’re faced with weeding overwhelm these principles will help get you back on track.


REDUCE Weed Pressure


The principle of weed reduction has to come first because other strategies will be futile if we don't take steps to reduce the pressure. To do this we need to understand where weeds are coming from. They all begin by either blowing in on the wind, spreading by root from nearby weed populations, or as seeds already within your soil. Once you know the main source(s) of your weed problem, you can take appropriate steps to reduce the pressure.


Weed reduction begins by purging your own soil of weed sources. We need to treat our soil like it contains an endless supply of weed seeds already, because it probably does! These weed seeds have an incredible ability to lay dormant for years and germinate only when conditions are right. The way we handle your soil will dramatically impact the number of weeds that pop up in our space. If we churn it up with a rototiller and add water, we inadvertently create the perfect scenario for weeds to grow. Every time we disturb the soil we bring dormant seeds to the surface and give them a chance to grow. This is why one of our primary strategies to reduce weed pressure is to avoid tilling. Our soil still contains countless weed seeds I'm sure, but as long as we don't till, the vast majority of those seeds will remain dormant inches below the surface and the weed population near the surface will eventually become exhausted.


If weeds are spreading from nearby sources by air or through roots in the soil, you can also take steps to reduce this type of pressure. Roots can be stopped by burying edging in the soil and covers can be used in a timely fashion to reduce the impact of unwanted seeds blowing in on the wind. For example, one of the weed pressures we face in the city are the seeds of elm and maple trees. Fortunately, these trees release their seeds during a limited window of time so we can cover beds temporarily to force the seeds to land to the side and not mix into our garden soil.


These two beds are covered with a flood of white Elm seeds in early June. Netting can be used to prevent the seeds from landing on the bed space and save weeding labour in the long run..

REMOVE Weeds Frequently and Thoroughly


When you approach a weed in your garden ask yourself whether you would like to remove it once a week or once and for all. Whenever I have been a part of garden work bees and the task of weeding is a part of the session, I can always spot people "removing" weeds by grabbing the leaves by hand and ripping them out. This practice might seem initially gratifying and effective, but it leaves many weeds in a position to quickly rebound. Weeds like Canadian Thistle, Dandelion, or Quackgrass can easily regrow from their roots or even fragments of their roots. In fact, a new Quackgrass plant can sprout from a single node anywhere along its long tenuous roots, so when you till up a patch of invasive grass to start a garden, you're really slicing up the roots into fragments and spreading them around your garden so they can multiply even faster. The lessons here are to avoid tilling (again) and to always remove the entire weed when the plant has the capability of regrowing from its roots. If you don't do it right the first time, you'll be doing it again next week.


The taproot of a Dandelion extends deep below the soil and if it is not removed fully, the plant can easily regrow.

On that note, you should probably spend a little time weeding again next week anyway. The task of weeding worsens with time: the more time you give the weeds to become established, the longer it will take you to thoroughly remove each one of them. However, if you take the time to weed frequently, the task is quick and much more enjoyable because you always feel like you're ahead of the game. How much is a "little time" weeding? Well, we're now spending around just 10 minutes a week per 1000 square feet of garden space. This work entails a quick walk through our pathways with a stirrup hoe and pausing to pull out any weeds in the beds whenever they pop up.


When you fail to remove weeds regularly and give them the upper hand, the season doesn't usually end well. The story usually goes something like this. You begin to dread the inevitable task of removing weeds as they become bigger and bigger. You know you won't be able to catch up in one work session, so the thought of doing all that work scares you and you end up putting it off even longer. Before you know it, the dream of a vegetable harvest is overshadowed by the immense task of weeding so you just give up on the season and have the garden tilled again the next spring. Sadly, this path only leads to even more weed pressure next season because all those weeds you didn't remove will have gone to seed and added to the bank of weed seeds already in your soil.


Writing a different weed story for yourself takes discipline, not time. If you can't spend just 10 minutes a week keeping your garden weed free, gardening might not be for you. If weeding is taking you more than 10 minutes a week, then you need to make a change in one of the other R's of weed management.


RECLAIM Bare Soil


Plants are all like superheroes in a way. They each have an ability to do something really really well to fill a niche, and the plants we consider weeds are really well adapted for the task of populating empty spaces. Therefore, a big part of weed management is minimizing the amount of bare soil.


Vegetable gardeners are especially challenged with weeds because our soil is usually bare for at least portion of the year, but we can still take steps to reclaim this space quickly before the weeds take it back from us. Whenever we create bare soil in our garden, our objective is to cover it as soon as possible.


The first form of ground cover that is always working for us is our compost. Whenever we add compost to our garden beds, we only spread it on the surface. We don't mix it in. This way a blanket of weed free compost serves as a buffer zone between the sunlight above and the bank of weed seeds in the soil below. The seeds that do manage to germinate below the compost are much less likely to actually make it to the surface.


The most productive way to cover the soil is with vegetables of course. We do our best to have a crop growing in all of our garden space throughout the whole season because a thick cover of healthy vegetable plants can go a long way to keeping weeds at bay too. Starting beds with transplants, as opposed to seeds, makes it possible for us to cover spaces even faster.


The use of wide 30 inch beds creates a continuous ground cover of vegetables.

Lastly, we can use a range of mulch options to cover any bare soil surface. Despite our best planning efforts, there are still times when some of our beds are open during the growing season. For these instances, we have a stash of tarps and landscape fabric at our disposal to cover the soil temporarily. It only takes a minute or two to lay down a tarp, and I'm always glad I did it because I can pull up that tarp weeks or months later and reveal a weed free space that is ready to plant. In the video below, landscape fabric is used to temporarily cover beds while a thick layer of wood chips is used to suppress weeds in the pathways.



The use of tarp covers in our garden can also extend to areas that never grow vegetables like walkways or storage areas. An organic mulch like leaves, straw, or wood chips can work in these areas too, but I still find it most effective to include an impenetrable plastic layer of some kind, whether or not an organic material is added on the surface. Once a weed free surface is established over a couple of years, the plastic is less necessary and a thick layer of organic material will suffice. Wood chips are our top choice because they last a long time and we can access them pretty easily in our city.


Landscape fabric is used to smother grass and weeds on our boulevard plot, and a light layer of wood chips is added for aesthetics and to prolong the life of the landscape fabric.

I know weeds can seem invincible at times, but the truth is that they are still just plants, and plants need light to survive. By covering the soil, you make it really hard or even impossible for the tiny weed seedlings to reach the surface, and this ultimately allows you to win the war.


I hope you'll take these three principles of weed management and put them into practice in your own vegetable plots. If you consistently reduce your weed pressure, remove existing weeds frequently, and always reclaim any permanent or temporary bare soil around your vegetables, the act of gardening will shift from a labour of weeds to a labour of love.


For more information about the various covers we use in our vegetable gardens see the Classroom post “The 7 Types of Covers We Use in the Garden”. Just type "covers" in the Classroom search bar and the post will pop right up for you.


Are you ready to put your hands where your heart is?

Join over 1000 other growers in our private online Classroom where we share specific information on the tools, methods, and resources you need to grow our own food.

Feel free to contact us with any ideas or questions you may have about growing vegetables!

© 2019 Vegetable Academy