Weeds are a very real part of gardening. Preparing your garden before the seasons starts is one of the easiest ways to remove weeds from large areas.
After all, a weed is just a plant that is growing in a space you don’t want. Mother nature has a wonderful gift for filling in any bare dirt with a new plant.
Weeds can very quickly get out of hand. Especially if you have had a bad weed problem in past seasons. Anytime a weed is allowed to flower and go to seed it further exacerbates the problem.
So how to win the battle? Or at least keep it in the manageable range.
In this article I will discuss powerful organic methods of pre-season weed suppression as well as the tools & materials used.
Learn how to prepare a weed free garden before you start planting and how to help keep the weeds down during the season.
Step 1: Solarization
A powerful method for tackling even the weediest spaces on a large scale. You can use this to prep a space that has never had a garden in it or a bed that is overrun and totally unusable.
This will help you prepare even the weediest gardening spaces for planting for the upcoming gardening season. The effect is dramatic. You will want to use this as more of a long game approach as it takes time for it to be really effective.
Let me explain why it is a must! I have used this to recover a portion of my garden from a severe chickweed infestation.
So how does it work?
You will cover the entire space you are preparing for growing with a thick black plastic that does not have holes. Silaging tarps are quite commonly used by gardeners as they are huge and do not breathe. The key to this process is the greenhouse effect created under the tarp. The plastic maintains a warm, moist environment that stimulates weed germination but blocks out light, and subsequently kills the weeds. In some cases if it gets hot enough you can even sterilize the seeds without having them germinate. This can also work to sterilize pathogens in the upper layers of soil.
Soak the entire area you want to cover with water beforehand. The humidity is needed for full effect and to germinate seeds. Cover with the area fully with the tarp. Use either anchors or big rocks to secure it well. Leave on the soil for a minimum of 6 weeks in the winter or very early spring.
During the growing season when the sun is much more intense this can be successful in as little as 3 weeks.
Depending on the season, if the snow has melted early enough before planting (or you don’t get snow) you can start the process of solarization before you want to start planting. Be sure you can allow for the 6 weeks to ensure maximum effectiveness.
Does it have to be a black tarp?
In truth, no. However, the black is a key part of speeding up the process. Blocking out the light inhibits growth in plants. I have actually never used a black tarp. The first few years I did this I just used what I had around which was a roll of vapour barrier (used in home building in between the insolation and the drywall). Vapour barrier is a thick clear plastic. I layed the plastic over the wet soil and then covered it thickly with tree mulch. This allowed the heat and moisture to germinate the seeds and the darkness was achieved with the tree mulch. This worked well for me because we have easy access to free tree mulch.
I do, however, recommend purchasing a black tarp as opposed to doing it the way I did. Hauling mulch and shovelling it into place is extra work, even if it is free. If you have a super large area to cover it would not be feasible. I was doing just small raised garden beds, about 100 sq ft each.
Don’t have time for solarization this year?
No worries. On to plan B! Now that you know what solarization is and how to use it, you can prepare to action it in the fall or next spring.
This year to get ahead of the weeds… you are going to water them.
That’s right. You are going to water your dirt for a few weeks before you plan to start direct sowing or transplanting. It doesn’t have to be super deep watering. Weeds are pretty tenacious and can make do with a lot less.
By doing this you are going to intentionally invite the weeds to germinate. Once they have sprouted you can remove them easily without having to work around your precious vegetable and herb seedlings.
This might sound crazy but think about what happens when you start to water the seeds you have direct sown. You will inadvertently also be watering weed seeds. Then the weed seeds will happily sprout at the exact same time our seedlings sprout.
There is nothing worse than trying to weed around your tiny little carrot or lettuce seedlings. I don’t know how many times I have pulled the wrong thing by doing this. Half the time you’re just trying to discern what is a weed and what is your vegetable.
Step 2: Weed Suppression between rows or garden beds.
If your garden is large enough that you can walk in between the rows this works well for keeping the weeds down in between the rows. This is also a great way to suppress weeds in between raised garden beds. Both of these methods suppress weeds and help to prevent new ones from growing.
These 2 methods work equally as well. Each with their own unique benefits.
Option A: Covering the in between space with landscape fabric.
This option is great because you can move the row cover fabric from season to season to different spaces. You can even use it to cover an area you want to plant next season.
By covering either the rows or a future growing space you are not allowing weed seeds to sprout and grow. It also prevents new weed seeds from landing and sprouting during the season. The downside is that this is not as aesthetically pleasing to have black landscape fabric covering everything.
Option B: Using cardboard covered in tree mulch in between the rows.
The advantage to this method is both aesthetic and function. The mulched in between spaces looks quite nice from a landscaping stand point.
The second major advantage is that using cardboard with tree mulch on top will also compost down over time. If your soil is poor to start with this can be a huge benefit as you are slowly introducing more organic humus material to your soil which in turn is building you considerably better soil for your plants.
This will suppress weeds and grass amazingly well when put down. It will however, slowly start to get new weed seeds sprouting in it as they blow in from neighbouring plants and spaces. Mulch does not allow weeds to root really deeply though and often and quickly back and forth with a push pull hoe and they pop right out.
Keep Grass & Neighbouring Weeds Out
If you have neighbouring grass and weeds that are forever creeping into your garden then use this method to build a border around the garden to stop the weeds and grass from finding their way into your garden.
Winning the battle with weeds without dumping chemicals on them requires a little more diligence but can be very effective.
If you repeat these processes each season wherever you can you will notice a significant reduction in the weeds that want to sprout. My arch nemesis chickweed has seeds that can hang out in the soil and germinate up to 7 years later! Some weeds are very tenacious. I can say that I am winning the battle with chickweed though using these methods!
What type of garden does this work best in?
This works well on smaller urban raised garden bed type spaces and large open plots. I highly recommend using both solarization at both the start and end of the season if you have the time before the snow starts to fall or after it has melted in the spring. The more times you can apply this the more dramatic results you will see in just a few seasons. It will significantly reduce the potential weeds that will sprout on you. Follow this with using the mulching or landscape fabric weed suppress in between your garden beds, down the rows in the garden or on the edges of your garden.
Phase 3: Water Your Weeds
You will notice I have this under the Solarization section above as the alternative option if you don’t have time for that process. I do also recommend watering your soil for 2 weeks AFTER solarization as well. Refer back to “Don’t have time for solarization this year?” for the full process.
This is your triple threat. It will have massive impact on the overall weeds that will sprout during the growing season. Do this for a few years in a row and it will be like growing in a whole new space filled with deep breaths and easy maintenance.
The catch is you need quite a bit of time to do both solarization (min. 6 weeks) and watering the soil (min. 2 weeks) prior to direct sowing or transplanting. That is approx. 2 full months of prep prior to starting your garden. So do both if you can or choose the one that fits your time frame the best.
You can also start this mid to late summer and into the fall to get a jump on next year.
Optional Phase 4: Keeping Tree Seeds Out Of Your Garden
This is for those of you who have trees in your yard or neighbouring yard that drop a boat load of seeds on your garden, and in your yard in general. In my case, it is the abundance of elm trees in my yard and neighbouring lots.
This presents one of the biggest weeding challenges in my space but can be overcome.
You are going to want to purchase yourself a leaf blower / vac. This is my best friend for yard cleanup for both seeds in the spring and leaves in the fall no matter the size of yard.
When the seeds start to fall, keep your leaf blower handy. Every chance you get for those couple weeks that the seeds fall use your leaf blower to gently blow the leaves out of your garden and from around your plants, hedges, trees, etc. Blow them into little piles on your lawn and use the lawn mower to pick them up. You can also blow them into little piles and use the vacuum attached to suck them up.
This not only works to blow seeds from your garden but you can remove the seeds from rocks you have in landscaping, from corners around buildings. You name it, you can blast the seeds out of the crevices where they will sprout into a nice pile and then scoop them up.
This works the best when the seeds are dry. So try to blow the seeds out of your garden before a rain or after a few days of heat.
If you have days where it is too windy to use the leaf blower part (which is often my case), the vacuum attachment is amazing. I often use the two in tandem. Blow the seeds and leaves into a pile and then vacuum them up. The vacuum attachment also maserates it into small pieces.
Weeding During The Growing Season
If you are in the middle of your growing season and need help getting weeds under control so your vegetable and herb babies don’t get drowned out then head over to my “How To Weed Your Garden: Winning The Battle During The Growing Season” blog post. You can use both this large scale method combined with my mid-season techniques to keep the weeds at bay and reduce your corresponding stress levels significantly!
Weed Suppression Supplies
Remove Weeds From Large Areas
Silaging Tarp https://duboisag.com/ca_en/polyethylene-silage-tarp-against-weeds.html?gclid=CjwKCAjwzruGBhBAEiwAUqMR8JOiMbgS4TFnjF6fyJO-1kbiuZgUYyxfxvrzbLKEahm03MfIriemXhoCmDwQAvD_BwE
Be sure to get UV treated argriculutre grade so it does not deteriorate and leach plastic into the soil.
Landscape Fabric https://amzn.to/3iUEiO1
Choose the most heavy duty landscape fabric you can afford. Both so you don’t have weeds coming through and so it lasts you a long time.
Landscape Fabric Pins / Garden Pegs https://amzn.to/3cXlZE5
Secure your landscape fabric properly with these pins.
Leaf Blower / Vac https://amzn.to/3wEhSod
This is a MUST have tool for every homeowner. Makes very quick work of large areas. Allows you to blast the seeds, leaves and other crud out of corners, and most importantly out of your garden. I use the blower and the vac portions equally.
Do not use a dyed tree mulch as it will release dye and chemicals into your soil. Choose a composted tree mulch from your local arborist or landscape supply company. Composted (it will not be fully broken down) is key as you do not want to introduce more weed seeds into your garden.
Use this as the base before adding dirt or mulch to an area to suppression grass and weeds. Put the word out to friends and family that you will be needing cardboard and/or newspaper. Alternately, reach out to a local appliance store and ask for extra boxes they have.
Follow this with my powerful mid-season weeding method “How To Weed Your Garden: Winning The Battle During The Growing Season” and what the weeds will no longer cause you overwhelm and stress. In fact, the more you apply these methods on repeat the less weeds will have the opportunity to re-root or to flower and drop their seeds in your garden to sprout in future seasons.