Safe, Effective Solutions to Prevent Weeds From Growing in Your Garden

The first weed sighting of the season is a feeling all gardeners know well. But if you think back-breaking work or pesticides are in your future, think again. You won’t need to reach for toxic chemicals when you learn about these organic, eco-friendly techniques for safe and effective weed prevention.

What is a Weed?

“A weed is a plant that has mastered every survival skill except for learning how to grow in rows.” –Doug Larson

It’s good to know what a weed is before you try to deal with them. Weeds are plants growing in an undesirable or unintended place. They typically grow easily with little maintenance or care, often sprouting up and taking over. The situation can get out of control quickly if you don’t address it.

Not all weeds are bad though! From an integrated pest management (IPM) lens, any growing plant is better than bare soil. Plus, some people intentionally grow dandelions and stinging nettle for food.

 Weeds:

Your tolerance as a gardener is important to think about here. If you’re ready to understand the relationship between weed prevention and garden health, let’s dig in.

Identification Tips 

Not all weeds are the same. Annual weeds sprout only from seeds. Biennial weeds sprout from seeds and live for 2 years. Perennial weeds grow from seeds and their roots, living longer than 2 years.

During California’s cool, rainy season, we often see oxalis, chickweed, and other grasses. In the warm, summer months, annual purslane, mallow, crabgrass, and perennial bindweed are common. 

When you know when to expect weeds, you can better prevent them.

Prevention Strategies to Reduce Weeds

My go-to strategy for preventing weeds in my garden is using cultural controls. This IPM approach involves adjusting the environment to make it less desirable for weeds and pests to grow. For problems in your garden, it’s smart to begin with the foundation.

Start in the soil

Did you know you can understand the pH of your soil by assessing the different weeds growing in your garden? 

For example, dandelion and stinging nettle prefer acidic soil whereas queen anne’s lace is often found in alkaline soil. You can change the pH by adding garden lime or sulfur – just make sure you don’t disrupt the plants you want to stay! 

If you have nutrient-poor soil, sheep sorrel and yarrow will thrive. Your nutrient-rich soil will produce chickweed and purple deadnettle. If you make any changes to the soil, be sure to do it with care. 

Look at irrigation and drainage

Another strategy is to amend your soil by adding organic materials or minerals to improve its drainage or water-holding capacity. This prevents dock, chickweed, and purple loosestrife from popping up. I recommend a drip irrigation system to allow for efficient, localized, deep watering of just what needs it – leading to fewer weeds.

You can also aerate your soil to reduce compaction. This decreases the chance of field mustard and thistle growing since they thrive in hard, compact soil. Just remember that the less disturbance to your soil, the better!

Beware of hitchhikers

No matter how careful you are, weed seeds can enter your garden by chance. They may end up in your garden from:

  • Hiking clothes

  • Lawn mower equipment from hired gardeners

  • The wind

  • Potted plants from the store

  • Pet’s fur

  • Birds

Knowing this, you can take precautions – like building a weed barrier – to limit your garden’s exposure.

Crowd weeds out

Another way to get ahead of the weeds is to grow more of your desired plants. Don’t forget to select the right plants for the area though. Consider the water needs, soil type, and ideal sun exposure before you plant.

When you plant densely and your garden is healthy, you prevent weeds from finding room to grow. 

Plant cover crops

Soil does not like to be bare. So, instead of waiting for weeds to take over your vegetable garden after a harvest, consider planting cover crops. 

A few of my favorite options for this (besides perennials or shrubs) are:

  • Crimson clover

  • Fava beans

  • Oats

  • Rye

  • Vetch

Add mulch

Mulch is anything covering the soil surface such as wood chips or straw. Apply a 2-3 inch layer of organic mulch to provide the most benefits for your garden when it comes to keeping it healthy and free of weeds.

Learn the what, why, and how of sheet mulching with this helpful guide I prepared for you!

Mulch keeps weeds from sprouting and growing. It also adds nutrients to the soil, feeds soil organisms, saves water by reducing evaporation, reduces soil compaction and erosion, and keeps soil cool in summer and warm in the winter.

Effective Weed Management 

Try as you might, sometimes prevention isn’t possible. If weeds are actively growing in your garden, there are tips I have to safely and effectively manage them.

The best approach is using mechanical controls, which involve removing pests and weeds from your garden with physical devices or barriers. You might not like to hear this but… the safest way to get rid of weeds is to hand pull them early and often when the soil is dry.

Don’t get overwhelmed though! Focus on key areas of your garden that you want to clean up, start small, or buddy up and host a weeding party.

Weeding tools 

If you have weeds in your garden, there are a variety of options for tools to remove them depending on the type of weeds you have.

There is a tool specifically for dandelions. Some tools pull, dig out the root, or slice the tops off. Hand tools of all shapes and sizes exist or you can get tools that you use from a standing position like a Hula-Ho. 

There are also heavy-duty tools for tough weeds like weed pullers, line trimers, and mowers. Or you can get weed steamers and torches during the rainy season to burn off the weeds between cracks or in gravel walkways. I have the Weed Dragon weed torch – it's super easy to use and lightweight. 

When you use a weed torch, only do it during the rainy season and when there is little to no breeze. Do your part to prevent a fire!

You don’t need them all. Find a few that work for the weeds you see in your garden.

Weeding hacks

Sheet mulching is a popular, inexpensive method for controlling weeds (especially perennial weeds). How do you do it? Layer cardboard over the problem area and top with 3-4 inches of mulch. Be sure the cardboard overlaps to block the sun from the weeds and prevent growth. This is a great garden hack to keep weeds like buttercup oxalis at bay.

However, if the idea of manual weeding makes you squirm, consider renting grazing animals like goats to manage it. Not only does this benefit your garden, but it’s also cute!

Weeding tips

Start weeding at first sight to prevent it from getting out of hand. Early and often is the goal! Also, avoid adding weeds you pulled into your compost pile to stop it from spreading.

Weeds in turf areas might look like a nice lawn at first glance. However, it is not because it is full of weeds and lacks deep root systems or healthy plants. Feeding the lawn organically and watering deeper will help its health and keep weeds in check.

If you want to get rid of weeds, you need to know what you’re dealing with. So don’t be fooled! Crabgrass is often misidentified as other look-a-like such as:

  • Dallisgrass

  • Goosegrass

  • Large crabgrass

  • Smooth crabgrass

  • Witchgrass

  • Bermudagrass

Cultural controls like hand pulling at first sight and protecting the soil with mulch to prevent weed seeds from growing are the easiest ways to manage the spread of crabgrass in your garden.

Using Herbicides AKA Weed Killer 

We’ve discussed mechanical and cultural controls for managing weeds, now let’s talk about chemical controls. 

Herbicides are designed to kill plants. Weeds are plants, but so are your favorite patch of wildflowers. If you’re going to use a pesticide or herbicide, please read the label well. Here’s what to look out for:

  • What the active ingredient is

  • How it’s meant to be used

  • Directions for use

  • What pests it manages

  • The precautionary statement

A note about herbicides: Timing is important. Some kill weeds quickly, others take weeks to work. Some can stay in plants or soil for a long time while others have active ingredients that move through the soil, contaminating the groundwater.

There are a few effective active ingredients to look for in herbicides. 

  • Ammonium Nonanoate: Broad spectrum, non-selective contact herbicide ammoniated pelargonic salts. Used to manage weeds, grasses, mosses, and lichens. Fast acting and OMRI listed. The brand name for this is Ortho Ground Clear (look for the green banner on the black label).

  • Ammoniated Soap of Fatty Acids: Fast-acting herbicidal soap. Use when warm and dry. This is a non-selective top kill for grasses and broadleaf weeds that can also be used on algae and moss. Many brands bottle this active as a weed and grass killer.

  • Horticultural vinegar: Fast-acting, top kill, and OMRI listed. Use with caution as it can burn skin, eyes, and lungs. Recommended brands are Harris Weed & Grass Killer.

No pesticide is risk-free, so get curious about the products you’re using. Even eco-friendly or DIY pesticides produce unintended consequences for the environment and ecosystem beyond your garden. So think before you spray! When it comes to weed management, the goal should always be prevention.

Ways We Can Grow Together

Yes, weeds in your garden are frustrating. But with proper care and prevention strategies, you can keep them at bay. 

And as your resilience grows as a gardener, you won’t need to reach for herbicides as soon as weeds appear. The best way to manage the problem is to be proactive and use eco-friendly methods that don’t harm the environment. 

Have more questions about how to prevent weeds from growing in your garden? Send me an email and I’d be happy to answer them.

Suzanne Bontempo