Cover crops are plants that are grown to cover an area and improve the health of the soil. They are not grown for consumption. Pansies are most often planted during winter, but they can also be planted at other times of the year.
Farmers and gardeners are adopting cover cropping techniques from natural ecosystems. If you look at any natural environment, you will see that cover cropping is happening naturally. Growth will happen in any environment where conditions allow it.
What are the advantages/benefits of growing cover crops?
So many!!! Some of the most important include:
- Adding fertility to soil by capturing atmospheric nitrogen (nitrogen fixation by legumes)
- Increasing soil organic matter and increasing soil biological activity (by growing biomass)
- Preventing soil erosion and compaction from fall and winter precipitation (by providing ground covering)
- Capturing and cycling nutrients (especially leachable nitrogen)
- Improving soil structure and “tilth” by the action of roots and in the decomposition of plant material
- Improving drainage in the soil through root penetration and increase in soil organic matter
- Suppression of weeds and conservation of moisture (by providing ground cover)
- Increasing habitat for beneficial insects
- Pest and disease suppression
What are the different types of Cover crops?
Cover crops can be classified into three categories – legumes, cereals, and grasses – each representing a different plant family with its own unique benefits.
The grass family of plants are very useful in agricultural systems where crops are grown in a sequence, with one crop being harvested before another is planted. The reasons for this are numerous, but include the ability of grasses to suppress weeds, improve soil health, and provide a source of food and shelter for beneficial insects. Fibrous root system are good at making soil better for plants, water, and air. Sedges are effective at preventing erosion and suppressing weeds because they cover the ground and crowd out other plants. Their vigorous vegetative growth also increases the level of organic matter in soils.
The Legume family is the only plant family in the whole plant kingdom which has the ability to capture Nitrogen from the atmosphere and store it in the soil. Legumes work together with specific strains of bacteria that live on their roots to get things done. . The most important contribution of legumes is nitrogen fixation, but they are also helpful in increasing soil organic matter, suppressing weeds, and providing habitat for beneficial insects.
Brassica (“Cabbage” or “Mustard”) Family
Some members of the Brassica family are cover crops. Soil compaction can be a problem for farmers as it prevents moisture and air from reaching plant roots. Daikon radishes have long, thick roots that help to break up compacted soils, making them a valuable tool for farmers. Other Brassicas can help suppress pests and diseases by releasing natural chemicals from their roots. Brassicas are important for scavenging and cycling nutrients because their roots are so deep.
Buckwheat is often used as a cover crop during the summer, so it is worth mentioning here. Buckwheat grows more quickly than most food crops and weeds. It is often used as a quick-growing crop that provides protection for food crops. This plant is excellent for increasing soil organic matter, and its early-flowering blooms provide an amazing source of nectar and pollen for bees and other beneficial insects.
How Should I Plant My Cover Crop?
Clear the area of all plants before cover cropping.
Till the surface of the soil with a tilting fork, hard rake, or garden claw. If you want to sow very small seeds (such as clover), create a seed bed that is fine and has minimal clods. If you are planting larger seeds, such as beans or peas, you only need a coarse seedbed.
Step 3: Spread the seeds by hand following the recommended seeding rate.
Use a hard rake or hoe to chop the seeds you have sowed into the ground.
. Step 5: Water your plants with an overhead sprinkler only if it is not going to rain within a few days.
Woohoo! You’re done! Cover crops are extremely self-sufficient. The winter rains will help out until you’re needed in the spring!
Types Of Cover Crops For Raised Beds
Below we’ll discuss the most common types of cover crops and why they will be beneficial for your raised bed. There are cover crops that prefer to be planted in early spring, early fall, winter, and even perennial. The best way to reduce soil erosion and soil compaction is to add plenty of organic matter to your raised bed soil. Cover crops help with weed control by providing dense cover. Some plants can be used as both food and medicine. They can be picked early or allowed to grow to full size.
There are four main types of cover crops to choose from: annual grasses, annual legumes, annual brassicas, and annual broadleaf plants. You will plant these cover crops four weeks before the first scheduled frost date unless you are instructed to do otherwise. The plants will be left in the soil over winter to protect it from the elements. Negative Cover crops can help prevent weeds from growing.
Buckwheat is a cover crop that can be grown very quickly, at any point in the growing season. This plant is a great choice for suppressing weeds in your raised bed because it has an allelopathic effect. You can eat it and cultivate it for its microgreens, or let it grow until it matures so you can collect the seeds to make flour. Although it is important to remember that most cover crops are not grown to full maturity, as this would cause them to draw nutrients from the soil instead of replenishing it. Buckwheat is often grown as a summer or fall cover crop. The plant is very sensitive to frost and will die when it is exposed to frost. If you don’t want to harvest the frost-killed buckwheat, you can leave it in place and it will act as a living mulch.
Alfalfa is a type of cover crop that belongs to the pea family and is good for the soil because it helps to fix nitrogen in the ground. It’s beneficial to plant it after crops that have used up nitrogen from the soil, like corn. It is fed to farm animals as forage because it is high in protein. This plant will also produce beautiful purple/blue flowers that will provide food for pollinators, which is much needed. You can chop this cover crop and drop it, using it in the same way you would straw mulch. Cut the foliage of your plants back to the soil level and drop them onto the ground. Allow the leaves to dry out and break down over the winter. Then when spring comes, plant your next crop as usual.
Where to begin? There are well over 300 different types of clover, not just the common 4 leaf variety! Many of them can be used as cover crops in raised beds. A few popular types of clover include white, red, and crimson. Clover is part of the legume family, which includes peas, beans, and peanuts. They improve the nitrogen in the soil by growing nodules along the roots. Clover is a plant that grows in early spring and has a habit of spreading, which makes it good at preventing the growth of other plants that are considered weeds. Crimson clover is often one of the first flowers to bloom in the spring, which is good for bees and other beneficial insects.
Rye is an excellent option if you’re wanting to add a lot of biomass and organic matter to your soil. The most common type of cover crop is cereal rye, such as winter rye. Winter cover crops have fibrous roots that add a lot of biomass below the soil when left to decompose. Although it can withstand severe cold, it is not likely to die naturally during the winter months. If you want to turn the plant into mulch, you may have to kill it first. There are three ways to get rid of winter rye: mowing it, chopping it and dropping it, or covering it with a tarp.
Oats are a type of grass that can be grown during winter and spring. This is a great option for home gardeners who live in a temperate climate that has a shorter growing season. Oats can either be sown in the fall and harvested the following winter, or they can be sown in the spring and harvested in late summer.
Hairy vetch is a plant that, like rye and oats, can survive the winter in most areas. It is best to use it as a mulch. It is a great choice for improving sandy soil. It will help keep the ground moist and prevent more dirt from being washed away. This winter cover crop is also a legume, which means it will absorb nitrogen from the air and fix it into the soil. Hairy vetch produces beautiful small purple flowers as well. Vetch is also good for ground cover because it spreads out. Although it can be seen as a problem because it grows rapidly across the ground, it is usually easy to control and doesn’t usually harm strong, natural plants.
Sorghum can be used as a winter mulch to protect your soil from harsh elements or from weeds. Its extensive root system means it adds a lot of organic matter to your soil. seeded in the fall and either cut down a few weeks after it sprouts or let the winter frosts kill it.
There are many types of millet, but most commonly pearl millet is used as part of a mix of seeds for a cover crop rather than being sown on its own. Millet is a grain that can tolerate hot and dry conditions very well. It can also tolerate sandy soil. Millet is a type of grass that can easily produce seeds to grow more plants the following year. This plant can be used as a cover crop, but it will spread if the seeds are not removed.
Known by many as black-eyed peas, field peas are also a popular choice. They have a long taproot which is good for preventing soil erosion. They can withstand high temperatures and little water, making them a good option for gardeners in hotter climates. Cowpeas can help improve the nitrogen levels in your soil, and they can also be eaten if you let them mature.
Regular peas are not tolerant of heat or drought like cowpeas and are best considered as cool-season cover crops. Did you know that peas are also part of the legume family? They have nitrogen-fixing properties. Peas can be grown in colder climates later in the season. The young pea plants can be used as mulch or harvested as edible pea shoots.
Lentils are a great cover crop choice in cooler seasons since they can withstand cold temperatures. However, they cannot survive below-freezing temperatures. Lentil seeds will germinate at 40 degrees Fahrenheit. Winter annual legumes are excellent at providing ground cover. Cover crops that are in the lentil family can tolerate dry conditions well.
Mustard is a great choice for home vegetable gardens that may be struggling with pests and diseases. The mustard will help to control the pests and diseases in the raised bed soil. The high levels of glucosinolates in mustard help to suppress soil-borne fungi and even nematodes. Plus, mustard greens are edible and quite delicious! The taproots of these plants can extend up to 3 feet below the surface of the soil, greatly improving the structure of the soil over time. If you don’t want mustard plants popping up everywhere, be aware that they will self-seed easily. On the plus side, you’ll have more ingredients for salads!
Barley can be grown in mild winter climates such as zone 8 and above, even though it is less winter hardy than rye. Barley has a deep and fibrous root system which enriches the soil with organic matter. The grass can be cut and left on the ground as mulch.
Winter wheat is the most common type of cover crop, followed by oats and rye. This plant is easy to grow from seed, grows rapidly, and can be planted in the fall and killed back by winter frost. This crop is a great choice for beginners because it is easy to grow and provides many benefits.
Oilseed radishes are used as a cover crop due to their deep taproots, which help to break up compacted soils. Daikon radishes are used as a cover crop due to their long roots, which help to prevent soil erosion. Oilseed radishes will grow faster than daikon radishes since oilseed radish roots are thinner. Oilseed radishes are edible, but are not often grown for culinary use. Since the oilseed roots are thinner, the plant is able to focus more on the foliage. This will provide you with more green manure to feed your soil microbes. The roots of the daikon radish can also be left in place to decompose in the soil quicker than the thicker root.
Daikon radishes can be planted as a cover crop and will also produce an edible harvest. If you are looking to aerate your compacted soil, root vegetables are a good option.