Cover Crops for Home Gardens: A Beginner's Guide to Soil Health

Are you looking for a way to improve the health and productivity of your home garden? Consider planting cover crops! Cover crops are a simple yet powerful tool for nourishing the soil, suppressing weeds, and slow erosion.

Field peas, oat grass, and vetch cover crop.

With so many different types of cover crops to choose from, it can be overwhelming to know where to start. That’s why we’ve put together this quick guide to help you become familiar with cover crops and how to choose one that is right for you.

Using cover crops in your backyard garden reduces your reliance on synthetic chemicals and methods for pest control, fertilization, and weed control. This can help create a healthier and more sustainable garden ecosystem for both you and the environment.

In this article, we’ll share our top tips for planting cover crops in home gardens so that you can reap the benefits of healthy soil and abundant harvests.

What are Cover Crops?

Cover crops are crops that are planted specifically to benefit the soil and the environment in the garden rather than for harvest. They are planted in addition to the crops you are growing to harvest. Common types of cover crops include grasses and grains, legumes, and brassicas.

Cover crops help protect the soil from erosion, maintain soil moisture, discourage weed growth, assist with pest management, add organic matter and mulch to the soil, and can even be used to break up hard, compacted soil. Cover crops can also help distribute nutrients throughout the soil, increase or decrease the amount of nitrogen, and attract precious pollinators.

What are Green Manures?

The term “green manure” has been used interchangeably with the term “cover crop,” but it is actually a type of cover crop planted specifically for its soil-building properties. It is intended to be worked into the soil as a form of organic fertilizer.

Green manures are a fast-growing cover crop planted when your garden is fallow, turned over, and incorporated into the soil while it’s still green. As it decomposes, it adds nutrients and organic matter to your soil. Green manures are often planted in the fall or winter and worked into the garden soil in the spring before planting the next crop.

Green manures are used as a soil amendment to help improve the overall soil structure and nutrients. While growing, their dense roots will outgrow weeds and help aerate the soil. After they are cut and incorporated into the soil, they can increase the fertility and moisture retention of the soil.

Green manures are very beneficial to your home garden’s soil. They will help amend the soil, add nitrogen and other nutrients, add organic matter, aid in water retention, and help deter weeds and protect the soil from erosion.

Benefits of Cover Crops and Green Manures

There are many types of cover crops to choose from that can help the soil in different ways. Using a cover crop or green manure in your home garden can be beneficial in many ways. But first, decide what you want most from a cover crop. Some common goals for cover crops are to:

Reduce Soil Erosion

Cover crops can help aid in soil erosion control in your home garden by holding soil in place with their roots, reducing the impact of rain and wind on the soil surface. It will also help the soil retain moisture when it’s hot and dry. This is especially important on sloping sites or areas with bare ground that are prone to erosion. Once the crop is terminated, it can be worked into the soil, adding organic matter, which further helps slow erosion.

Add Organic Matter

Cover crops or green manures can be planted to help add organic matter to the soil, which is important for maintaining healthy soil structure and fertility. Organic matter helps to improve soil texture, increase water-holding capacity, and support the growth of beneficial microorganisms.

Additionally, organic matter will break down over time, adding nutrients and improving the health and fertility of the soil.

Provide Weed Control

Many types of cover crops aid in weed control by outcompeting weeds for light, water, and nutrients. Additionally, the green foliage can be used as mulch when the crop is terminated, deterring weed growth in the area.

Fall cabbage plants companion planted with oat grass to help suppress weeds.

Improve Soil Fertility

Cover crops can add essential nutrients to the soil. For example, legumes like clover and beans can absorb nitrogen from the atmosphere and deposit it in a plant-usable form in the soil, making it very nitrogen-rich for the next crop.

The foliage can also be worked into the soil after it is terminated, where it will decompose and add nutrients and biomass to the ground. The organic matter in the soil will also help draw worms and other helpful insects into the soil.

Natural Pest Control

Cover crops can also provide habitat and food for beneficial insects, such as ladybugs, lacewings, and parasitic wasps, that will help control pests in your garden. These insects prey on pests like aphids, thrips, and spider mites.

Encourage Beneficial Organisms

Cover crops can support the growth of beneficial microorganisms, such as mycorrhizal fungi and nitrogen-fixing bacteria, which can improve soil health and plant growth.

Improve Soil Structure

Cover crops with deep root systems, such as radishes and daikon, can help to break up compacted soil and improve soil organic matter and structure. This can allow for better drainage, aeration, and deeper root growth for other plants.

Furnish Moisture-Conserving Mulch

Some cover crops can be left in place as a natural mulch, which can help conserve soil moisture and suppress weed growth. This can be especially beneficial in hot, dry climates or during periods of drought.

How to Choose the Right Cover Crops

To keep your home garden’s soil healthy and fertile, choosing the right type of cover crop can be hard when you don’t know where to start. Here are some tips to help you get started with choosing the right cover crop for your home garden:

• Determine your goals: Before choosing a cover crop, think about what you want to accomplish. Do you want to improve soil fertility, reduce erosion, suppress weeds, or attract beneficial insects? Different cover crops have various benefits, so choosing one that aligns with your goals is important.
• Consider your climate: Some cover crops are better suited to specific environments than others. For example, winter rye is a good choice for colder climates, while cowpeas are better suited for warmer regions. Choose a cover crop that can thrive in your local climate and growing conditions.
• Assess your soil type: Different cover crops thrive in different soil types. For example, legumes like clover and peas are well-suited for soils low in nitrogen, while buckwheat can tolerate poor soils with low organic matter. Make sure to choose a well-suited cover crop for your soil type.
• Plan for timing: Cover crops are typically planted between growing seasons, so it’s important to choose a cover crop that will have enough time to grow, terminate, and decompose before your next planting. Consider the length of your growing season and choose a cover crop that will work within that timeframe.
• Determine your planting time: Some cool-season cover crops are best for spring planting, while others are better suited as a fall cover crop. Choose a cover crop appropriate for your planting time and growing season.
• Determine your available space: Some cover crops, such as grasses, can grow quite tall and require a lot of space. Choose a cover crop appropriate for your garden’s size and layout.
• Consider the needs of your next crop: When choosing a cover crop, consider the needs of your next crop. For example, if you plan to plant a heavy feeder like tomatoes, choose a cover crop that can add nitrogen to the soil, such as clover.
• Plan for crop rotation: If you plan to rotate your vegetable crops, choose a cover crop that fits well into your rotation plan. For example, if you plan to plant tomatoes in a bed the following year, choose a cover crop that won’t leave behind residues that can harm tomato plants. Learn more about how crop rotation benefits your garden.

By understanding the different goals of cover cropping, you can choose the right cover crop or combination of cover crops to meet your specific needs and improve the health and productivity of your garden.

Types of Cover Crops to Consider

Now that you’re familiar with the benefits of cover crops and green manures in your backyard vegetable garden, it’s important to understand the different types available and their specific advantages.

It’s worth noting that there isn’t a one-size-fits-all solution when it comes to cover crops, as each type provides unique benefits that can improve the health of your soil and plants in different ways.

Cover crops are generally divided into three categories: legumes, grasses and grains, and brassicas. Let’s take a closer look at the different types of cover crops and what they have to offer:

Legumes

Legumes are part of the Fabaceae family, which includes various vegetables, herbs, and trees. Legumes can add generous amounts of nitrogen back into the soil, making them great for use as a cover crop before planting heavily feeding plants.

A great benefit of planting legumes as a cover crop in fall is protecting the soil over the winter months to help prevent erosion and suppress weeds. Some legume crops will survive winter and start growing again in early spring until they are terminated. While others are winter-killed, meaning they will die from cold temperatures and leave a good amount of green foliage behind to help prevent winter soil erosion.

The decomposing foliage can be worked into the soil in early spring, adding nutrients and improving soil drainage, making fall-planted legumes a great way to amend your soil before planting your spring garden.

Common types of legumes that are planted as cover crops:

• Alfalfa: Alfalfa is a deep-rooted legume that can add nitrogen to the soil and improve soil structure. It is typically planted in the fall and allowed to overwinter to begin growing again in spring.
• Beans: Beans are a common cover crop that can add nitrogen to the soil. They are typically planted in the summer, terminated before they go to seed, and left to decompose over winter.
• Clover: Clover is a nitrogen-fixing cover crop that is easy to grow and maintain. It helps to add nitrogen to the soil, which is beneficial for the growth of other plants. It also helps to suppress weeds and prevent erosion. Crimson clover grows up to 3 feet tall and has striking crimson red blossoms that attract pollinators. Clover can be planted in the spring or fall. Many varieties are winter-hardy and will start growing again in spring.
• Field peas: Field peas, sometimes called winter peas, are a cool-season cover crop that can add nitrogen to the soil and improve soil structure. You can plant them in early spring once the soil warms to at least 45˚F or from late summer to early fall.
• Hairy vetch: Hairy vetch is a fast-growing cover crop that can add nitrogen to the soil and improve soil structure. It is typically planted in the fall, overwintered, and terminated in early spring.
• Lentils: Lentils are a cool-season cover crop that can add nitrogen to the soil and improve soil structure. They are typically planted in the fall.

Legume cover crops are an excellent choice for improving soil fertility. They have the ability to add nitrogen to the soil through a process called nitrogen fixation, which involves converting atmospheric nitrogen into a form that plants can use. The plants also help to prevent erosion and suppress weeds. The best time to plant legume cover crops varies depending on the specific crop.

Crimson clover cover crop with red blossoms.

Grasses and Grains

Grasses and grains are cover crops or green manures that have dense root systems that help suppress weed growth and aid in soil erosion control. They can also absorb nitrogen from soil that has excess amounts of it.

Grasses and grains are mainly grown for erosion control, soil nutrient control, and weed control and can are worked into the soil once terminated.

Types of cover crop grasses and grains include:

• Barley: Barley is a cool-season, quick-growing green manure that can improve soil quality by adding organic matter and enhancing soil structure. It can be planted in early spring or fall in soil temperatures as low as 40°F. It will die in freezing temperatures and can be turned under in spring.
• Buckwheat: Buckwheat is a fast-growing, heat-loving green manure often used between growing seasons to suppress weeds and improve soil structure. The blooms also attract pollinators to the garden. Buckwheat is typically planted in the spring through summer and can be terminated by cutting and digging it under after it blooms before it goes to seed.
• Oats: Oats are a cool-season green manure crop that can add organic matter to the soil and improve soil structure. This is my favorite to plant in spring because it grows quickly and can be turned into the soil right before planting summer crops such as tomatoes, peppers, and squash. Additionally, planting oats in late summer can help prevent soil erosion during winter. The plants will die in winter, and the remaining oat stubble acts as a natural mulch, retaining soil moisture and preventing weed growth in the early spring.
• Ryegrass: Ryegrass is a fast-growing cover crop often used between growing seasons to prevent erosion and improve soil structure. It can also be used to suppress weeds by forming a dense mat. Ryegrass can be planted in the fall or early spring and is typically terminated by digging it under in the spring.
• Winter Rye: Rye, also called cereal rye or grain rye, is a hardy cover crop ideal for colder climates. It can tolerate frost and can grow in poor soil conditions. Rye is typically planted in the fall and can be terminated by digging it under in the spring.

Grass and grain cover crops add organic matter to the soil, improve soil structure, and prevent erosion. They can also help to suppress weeds and attract beneficial insects to the garden. The best time to plant grass and grain cover crops varies depending on the specific crop, but they are typically grown in the fall or early spring.

Ryegrass Cover Crop

Brassicas

When people think of cover crops, they usually don’t think of brassicas as being one of them. However, besides improving soil health, suppressing weeds, preventing erosion, and cycling nutrients, some brassica cover crops repel or deter pests such as aphids, flea beetles, and cabbage worms.

When the crop decomposes, it releases a chemical compound that helps eliminate soil-borne pathogens and pests, such as fungi, nematodes, and even some weeds.

Common types of brassicas that are used as cover crops include:

• Arugula: Arugula is a quick-growing, cool-season cover crop often sown in the fall or early spring. As a cover crop, arugula can form a dense canopy to help smother weeds and attract beneficial insects such as ladybugs and lacewings. Chop and dig it under before it sets seeds to add organic matter to the soil.
• Mustard: Mustard is another cool-season cover crop known for suppressing soil-borne diseases and pests. Plant mustard in the fall, chop the crop after it flowers, and dig it into the soil to decompose.
• Forage radish: Forage radish, also called oilseed radish and daikon, is a winter cover crop often planted in the fall. It is a deep-rooted plant that can help break up compacted soil and improve drainage. Forage radishes can also scavenge nutrients from deep in the ground and store them in their leaves, which can be returned to the soil when the plant is turned under in spring.
• Kale: Kale is a cool-season cover crop often grown in the fall or early spring. It is a nutrient-dense vegetable that is packed with vitamins and minerals. As a cover crop, kale can help suppress weeds, improve soil structure, and add organic matter to the soil as it decomposes.

The best time to grow these brassica cover crops will depend on your climate and the specific conditions in your garden. For example, arugula and mustard are best grown in the fall or early spring, while forage radish is best grown in the fall. Kale can be planted in the fall or early spring, depending on your climate.

Radishes growing as a cover crop in the garden.

How to Plant Cover Crops

Cover crops should be planted at the appropriate time for your region and climate. For example, cool-season cover crops like winter rye and clover are typically planted in the late summer through fall, while warm-season cover crops like buckwheat are planted in late spring for summer growth.

I tend to plant most of my cover crops at the end of the growing season. First, I harvest a main crop, such as garlic, onions, or carrots, then I succession plant cover crops in the same garden space, let it overwinter, and then turn it into the soil in spring.

Here are the basic steps for planting cover crops in a home garden:

1. Prepare the soil: Clear the garden bed of debris or old plant material. I like to scoop out a bucket of soil to cover the seeds.
2. Sow the seeds: Use a rake to smooth out the soil surface, then evenly broadcast the cover crop seeds over the garden bed. Cover with soil following the recommended planting depth for your chosen crop.
3. Water the seeds: Cover crops need consistent moisture to germinate and establish. Water the seeds immediately after planting and keep the soil moist until the cover crop is well-established.
4. Manage the cover crop: Once the plants are established, you can manage them by weed whacking or trimming them back periodically to prevent it from becoming too tall or going to seed.

By following these basic steps, you can successfully plant cover crops in your home garden and reap the benefits of improved soil health, weed suppression, and pest control.

Ways to Terminate Cover Crops

Cover crops should be terminated before they start to flower or set seed to avoid them becoming a weed problem themselves. You also want to make sure to terminate the cover crop a few weeks before you plan to plant your next crop, as it can take some time to break down and release its nutrients into the soil.

There are several ways to terminate cover crops in a small backyard garden. Here are a few options:

• Hand pulling: You can simply pull up the cover crop by hand or use a hoe for small areas. This can be a good option if you have a small garden or only planted a small patch of cover crop. Then, you can work the crop into the soil, use it as mulch on top of the soil, or toss it in your compost bin.
• Cutting or mowing: If you have a larger cover crop area, you can use a lawn mower or weed eater to cut it down. Make sure to set the mower at the lowest setting, so it cuts the cover crop as short as possible. After cutting, work the foliage into the top few inches of soil to decompose.
• Turning under: You can use a shovel or digging fork to dig up, turn over, and incorporate the cover crop into the soil. This is an effective way to terminate cover crops, but it can disrupt the soil structure, so it’s important to dig only when necessary.
• Smothering: Another way to terminate cover crops is to smother them. You can do this by laying down a thick layer of cardboard and mulch over the cover crop. This will prevent it from getting sunlight and eventually cause it to die.

Turning over a cover crop in the garden.

Take Notes

There is no right or wrong way to plant cover crops, so choose one that meets your needs, experiment with different planting times, and keep detailed notes in your gardening journal so you can narrow down what works best in your garden.

Be sure to record the type of crops you planted, seed sources, planting times, weather, termination dates, garden bed conditions before and after, and general observations and experiences with each crop.

Some examples of things I have learned along the way:

• Legumes, such as peas and beans, tend to attract deer that like to munch on the foliage.
• While brassicas stink like rotten eggs as they decompose after frost.
• Ryegrass forms a dense mat of roots that is difficult to remove. While farmers use heavy equipment to till in ryegrass, I had to dig it out with a shovel, chop it up, and add it to the compost pile because it was too dense to work it into the soil. I don’t plan on growing ryegrass again.
• The biggest lesson I have learned is if you let cover crops set seed, hundreds of plants will come up the following year.

Cover crops, green manures, compost, and mulch are terms frequently used when discussing ways to build and nourish your soil when growing food organically. Together, these techniques can help create a healthy and fertile environment for your backyard vegetable garden.

Cover crops and green manures can add organic matter and nutrients to the soil, while compost can provide a rich source of nutrients for your plants. Mulch can help retain moisture and regulate soil temperature while suppressing weed growth.

By using these techniques in combination with one another, you can create a thriving garden ecosystem that promotes healthy plant growth and minimizes the need for synthetic fertilizers and pesticides. Learn more ways to build healthy garden soil: 7 Simple Techniques to Improve Garden Soil.

—

Incorporating cover crops into your backyard vegetable garden can have numerous benefits. Cover crops offer home gardeners an affordable and sustainable solution, from improving soil health to reducing weed growth. I hope by following the tips outlined in this article, you can successfully introduce cover crops into your garden. So don’t hesitate, take the leap and start experimenting with cover crops in your backyard. With a little effort and patience, you’ll soon reap the rewards of healthier soil and thriving plants.