Must-Know Tips to Control and Prevent Weeds in the Garden

Sharing is caring!

When you first start gardening, you might expect weeds to be a minor annoyance. But you’ll find they can turn into an overwhelming and discouraging problem, if they get out of control. Left to their own devices, aggressive weeds like buttonweed and spreading grasses can take the place over in a matter of days in the spring and summer, stealing important resources from your crops.

Honestly, I don’t think there’s any such thing as a garden you don’t have to weed. Even with the deep mulch no-till methods we use, the weeds find a way. With a little work and a good prevention strategy, though, you can take your garden back and keep them down to a level that’s much easier to manage.

Short on time? Pin this for later.

What Happens When Your Garden is Full of Weeds?

A few weeds here and there won’t hurt anything. If your garden is totally choked with them, though, they’ll cause more than just an aesthetic issue.

Weeds that grow wild in your yard thrive because they’re well-adapted to the conditions there. Meanwhile, many annual veggies and flowers are more sensitive to things like high heat, drought, and big temperature swings. When the going gets tough, vigorous weeds can easily out-compete your crops for water and essential nutrients. They’ll flourish and spread while your veggie plants suffer from slowed growth and nutrient deficiency.   

Weeds can harbor pests and disease, too. Horse nettle (aka Jimsonweed), a wild cousin of nightshade crops like peppers and tomatoes, often carries Alternaria, the fungus that causes early blight in your tomato patch.

Various weeds can host other viral and fungal diseases that’ll infect your crops through insect feeding and blowing rain, if there’s a lot of them close by. On top of that, dense weed growth limits air flow around your plants, creating ideal conditions for disease-causing fungi to take hold.

Weed thickets also make a nice habitat for pests you don’t want near your garden, such as thrips, flea beetles, aphids, and leaf hoppers. They’ll provide a daytime hiding spot for slugs so they can make themselves at home near their favorite food source: your tender seedlings, flowers, and brassica crops.

How to Reclaim the Garden From Weeds

Preventative measures are a must to keep weeds under control without spending hours fighting them. If you decided to read this, though, there’s a good chance it’s already happened. You got busy with life and didn’t have time to pull weeds. Now, your garden is a weed jungle. They’ve spread and established deep roots, and cleaning it up at this point seems impossible. We’ve all been there.

Once weeds have invaded and occupied your garden, getting them all out is a marathon, not a sprint. It’s completely do-able, though, and there are a few methods you can use to make your job easier.    

Hand remove.

Pulling weeds the old-fashioned way is a pretty daunting task, if they’ve gotten bad. Don’t approach it with plans to get it all done in one afternoon, or you’ll end up feeling defeated. Instead, work on it a little at a time. Pick one small area to focus on each time you get a chance to pull weeds, and commit to finishing just that spot. Maybe it’s one row, one garden bed, or just three square feet.  

When you’re hand-pulling weeds, be thorough and make sure you get as much of the roots as possible. Perennial weeds will come back stronger if roots are left behind. Weeds pull much more easily if you wait until right after a good rain.

Note: If lots of weeds have established themselves and grown large close to your plants, aggressive weeding can damage their roots. Don’t pull during dry weather, since hard ground makes damage more likely.

Sometimes, it’s best to wait until your harvest is done to deal with those deep-rooted weeds that take a lot of dirt with them when yanked. Pull the shallow weeds that come out easily, and cut the embedded ones back to slow them down until your crops finish up.

Smother the weeds with a tarp.

Once your crops are harvested, you can smother a lot of the weeds using silage tarps or any other material that’s opaque and thick enough to block out ALL sunlight. Like any plant, weeds need sun to produce chlorophyll. They’ll eventually die back after some time in the dark.

Cut the weeds down short with a mower or weed eater before covering them. Once your tarp is in place, weight it down well on all sides so light can’t get in. Weeds are a lot less finicky than your garden plants, so any light that seeps through will keep them alive and well.

Tarping works best during warm weather, while weeds are actively growing. If it’s hot out, the tarp will smother most annual weeds within a month or two, but it’ll take longer when the weather is cooler. Some types of perennial weeds with tough root systems are hard to kill off completely with any amount of tarping; you may have to go in and pull some that re-sprout later.

Solarize your soil.

Solarization kills weeds by cranking up the soil temperature instead of blocking the light. This can be done by using thick, clear plastic sheeting (such as plastic painter’s drop cloth) to trap the sun’s heat. Get the soil hot enough, and it’ll kill both weeds and weed seeds. For solarization to work, you’ll need to do it in the summer, preferably when daytime highs are reaching at least 80 F.

First, cut the weeds back short enough your plastic sheeting can lay close to the soil surface. Soak the area to be treated with a hose (or wait until after a rain), since moist soil absorbs heat more readily. Once the ground is prepared, cover it with the plastic and pin it down along the edges so heat can’t escape. It should be completely “sealed,” with no gaps. Heavy t-posts work really well for this purpose.

If the weather is nice and hot, solarization takes a month or so to kill most annual weeds. While it’s unlikely this method will completely eliminate perennial weeds, I’ve found it slows them down considerably more than tarping does. The longer you can leave the plastic in place, the less re-sprouting you’ll have. 

If you’re wondering whether solarization will kill worms and other soil dwellers, the answer is largely no. Earthworms can easily tunnel away from the area when they don’t like the temperatures. Other soil organisms can burrow deeper. Solarization can, however, affect beneficial fungi like mycorrhizae. Fortunately, fungal populations can rebound quickly. After solarizing, you can apply compost and other organic amendments to help them re-establish.

How to Prevent a Weed Takeover

This sounds dramatic, but managing weeds proactively will change your life, y’all. Take some measures to slow down the weeds when you first start a new garden (or after a weed cleanout operation), and you’ll save yourself hours of work later.

Here are some ways to keep your weeds in check before they have a chance to take off:

Remove grass by the roots when you prepare a new garden spot.

Lawn grass is one of the most stubborn, invasive weeds you can have. So, it’s well worth the (considerable) time and effort it takes to remove it as thoroughly as you can. Some types of lawn grasses, such as Bermuda grass, will come back from just about any kind of abuse you subject them to. That’s where the term “zombie grass” comes from! 

We used a sturdy claw cultivator to twist the grass out one clump at a time when we started our current garden. You could also use solarization to kill off the lawn in your planned garden area, if you’re okay with waiting. For getting rid of grass, I wouldn’t trust solarization unless you can dedicate a whole year to letting that soil bake.

Use mulch.

Bare soil is a magnet for weeds! Mulch will reduce the amount of weeds that pop up, and any weed seeds that drift in will be loosely rooted and easy to pull when they sprout. Make sure your mulch is at least several inches thick, and keep it from touching your plants’ stems so they have some airflow.

Put down weed barrier in the fall.

To slow down weed growth even more, lay down a weed barrier like plain cardboard, newspaper, or contractor paper.  Some folks prefer to use the black weed fabric specifically meant for this purpose (personally, I don’t like the mess that stuff makes when it starts to degrade and fall apart). You can use weed barrier in your in-ground garden beds, beneath raised beds to stop grass from invading, and to help keep your walkways tidy.

Weed barrier over growing spaces needs to be laid down in the fall (or winter) so it has time to soften up and break down some before you plant in the spring. Make sure your barrier extends at least 6-plus inches beyond the edges of the garden, or you’ll have weedy borders.

In our no-till garden, we’ve found it’s not strictly necessary to cover entire beds with weed barrier. If we remove existing weeds first AND add a deep mulch layer, we can get by with just laying the barrier along the borders. That’s where weeds can most easily sprout around mulch and, once established, spread inward.  

You don’t need to spend money on weed barrier supplies. Find out when your nearby grocery stores do their stocking, and you can score a bunch of free plain boxes that are already broken down for you. The employees at my local Ingles probably know me as the crazy box lady, at this point!

Note: Weed barrier won’t kill turf grass or perennial weeds that are already well-established. They’ll just pop back up like nothing happened as soon as the barrier breaks down. You’ll need to remove or kill perennial weeds the best you can, first, then use the barrier so they can’t re-establish as easily from surviving roots.

Plant cover crops to suppress weeds.

Garden spaces that sit unused during warmer months provide an opportunity for weeds. Maybe you have a lull between summer and fall crops in your hot climate. Or, maybe you didn’t get around to planting anything else after you harvested your spring cool-season crops. Weeds will quickly overtake that space. Then, you’ll have a big job of pulling them all when you want to plant there again.

Instead of leaving parts of your garden empty, sow cover crops as a weed buffer. Fast-growing annual cover crops will quickly outgrow and suppress weeds. Cover crops benefit your soil in a number of other ways, too.

Read this post to learn more about growing cover crops: How to Plan and Plant Cover Crops to Improve Your Garden Soil.

Weed lightly and frequently.

Take a few minutes several times per week to go through and yank any weeds that turn up when they’re still small and easy to pull. At the least, make sure to grab them before they drop seeds! 

Making the Most of Your Weeds

Weeds aren’t actually out to get you, despite how annoying they are in the garden. They’re just nature’s way of repairing disturbed soil, preventing erosion, and remedying other soil problems.

Sometimes, weeds can provide a clue that your soil needs some attention. Dandelions are notorious for thriving in pavement; seeing a bunch of them might indicate the soil is too compacted and/or low in nutrients. Sorrel tends to take over where soil is lacking calcium, while an abundance of plantain, horsetail, or nettles might mean your soil is too acidic.

In addition to being good soil quality indicators, some weeds are also edible and/or medicinal. Dandelion greens are rich in nutrients, and their roots can be used to make an herbal tea to support digestion and liver function. Common plantain is a powerhouse for herbal wound care. We gather it every year to make plantain salve, which works wonders for promoting healing and preventing infection in cuts, scrapes, and burns.

Next time you go to pull weeds, take a closer look at them during the process. Try to identify what’s growing, what it could mean about your soil, and how you might can use it. That’s a good way to get a little knowledge and appreciation from one of the less enjoyable parts of tending the garden.