Tag Archives: cover crops

A Beginner’s Guide to Spring Cover Crops

January 28, 2025 Jordan Charbonneau Leave a comment

Fall cover crops are a common way to build healthy soil over the off-season, but what about spring? Spring is a key time for getting vegetable crops in the ground, but it can also be a wonderful opportunity to battle the weeds and revitalize the soil before transplanting or sowing your warm season crops. While not as popular as fall cover crops, spring cover crops can be an essential tool for small farmers and gardeners.

Why Plant Spring Cover Crops?

Cover crops have an enormous list of benefits, but it’s best to focus on just a couple of major goals when you’re selecting and planning spring cover crops.

Suppressing Weeds

Fast-growing spring cover crops are an excellent way to get a head start on the weeds. As they grow, they block out light from reaching the soil, preventing weed seed germination. Some may even out-compete annoying weeds like quack grass!

Oats or a mixture of oats and field peas are a great, quick-growing option for early spring weed suppression. As the season warms up, buckwheat is another great option for suppressing weeds, though you need to plant it after any danger of frost.

Boosting Nitrogen

Green manure crops (those cover crops you terminate and incorporate into the soil), can be a quick way to add nitrogen and organic matter before a cash crop. Nitrogen-fixing crops like field peas, hairy vetch, or in cool areas, Austrian winter peas, are excellent options for spring green manures.

These early spring green manures are perfect for sneaking in before summer heavy feeders like sweet corn, hot peppers, or tomatoes.

Growing Mulch

You can also provide mulch for transplants, with a spring cover crop. Growers cut, roll, or tarp spring cover crops like oats or buckwheat, killing the plants and leaving the material on the bed. Then they transplant summer crops like eggplants or squash directly into the mulched bed.

Resting Beds

Commercial growers and those folks with sizable gardens will often find it helpful to allow a garden or bed to have an entire season or year to “rest.” This is a great, cheap way to revitalize soil, though it affects your production capacity in the short-term.

In areas with long seasons like the Southeast, you will probably need to plan multiple successions of cover crops. However, crops like white clover, which will grow the year through, are another popular option.

Covering Pathways & Margins

Few people like mowing, but keeping garden pathways and margins cropped is important for accessibility and weed prevention. Adding cover crops to these areas can help you make the most of your mowing. Sow a crop like white clover, then mow and use the nitrogen-rich clippings to mulch beds or build compost.

Buckwheat spring cover crops in bloom — Buckwheat

Timing Spring Cover Crops

Understanding your timing is key to selecting an appropriate cover crop for your garden. When can you sow a cover crop? When do you need to terminate the crop? What is going into the bed next? When is your last frost and what is your climate like? These are all important considerations.

In the Southeast, you can often sow cool-weather cover crops in late winter or very early spring provided your gardens aren’t to water-logged. There are several great cover crop options, like oats, field peas, Austrian winter peas, white clover, and hairy vetch that are fairly tolerant of cold, moist conditions, and minor frost. Look up your hardiness zone to find out your last frost date.

Some cover crops like buckwheat, cowpeas, and sunn hemp thrive in warm weather. These crops are frost sensitive, so you’ll need to sow them after all danger of frost has passed.

Determining which crop to plant also depends on what your plans are for that bed. If you’re planning on planting that bed in late spring or summer, determine your planting date so you can terminate your cover crop a couple of weeks before that.

You can also use the warm-season cover crops later in the summer. For example, grow a bed of lettuce in early spring. When it bolts, sow the bed with a warm season crop like buckwheat or sunn hemp. Follow with a fall crop of bush beans.

Spring Cover Crops & Their Benefits

Once you have established your goals and timing for your cover crop, you can select the appropriate species for your garden. Here are a few spring cover crops we recommend and what they excel at:

Oats

Highly effective in cool, spring soil, oats are an excellent way to quickly add tons of organic matter to the garden. Oats mature in about 60 days. For cover crops, harvest them before they go to seed.

Field Peas

Field peas fix nitrogen and tolerate spring’s cool temperatures well. Their sprawling nature makes them great for suppressing weeds, too. They generally mature in 50 to 75 days. Cut or incorporate after they have fully bloomed but before they set seed.

Oats and field peas are a popular spring cover crop mix. The oats provide great structural support for the nitrogen-fixing peas.

Austrian Winter Peas

These cool-weather loving peas are a great nitrogen-fixing crop for the winter or early spring garden. As a bonus, they offer edible tendrils perfect for spring salads.

In most of the Southeast, we recommend Austrian Winter Peas for fall planting. However, in cool mountainous areas or northern regions, they do well in early spring.

Hairy Vetch

Hairy vetch is another cool weather loving, nitrogen-fixing legume. It’s generally best to sow hairy vetch in the fall, between August 1st and November 1st. However, it can be spring sown, and is common in vetch, oat, and field pea mixes.

You may cut vetch and use it as a mulch for transplanting into or till it under as a green manure.

White Clover

White clover is a perennial cover crop that’s fairly tolerant of trampling and mowing. It makes excellent lawns, borders, and pathways around vegetable gardens and its clippings can help give beds a rich boost. It’s also an excellent long-term cover crop.

However, it’s slow to establish and not as ideal for smothering weeds. You will need to prepare the ground and keep it moist.

Buckwheat

Buckwheat is an excellent option for weed suppression and adding organic matter. It’s incredibly fast-growing and puts on tons of mass which can act as mulch or help lighten heavy soils. It also attracts beneficial insects.

Buckwheat readily self seeds. If you’re using it as a cover crop, cut or roll it in 30 to 40 days when it’s blooming, but before it has put on seed.

Keep in mind that you may have different experiences in a different climate. For example, clover thrives where SESE is in the eastern United States but may struggle in arid climates.

Cover crops are a cost-effective, organic way to improve your soil in any season. Selecting appropriate spring cover crops can help you increase soil fertility, add organic matter, suppress weeds, and attract beneficial insects. Which will you be sowing this season?

Garden Advice

Red Clover: A Cover Crop & Herb

May 7, 2024 Jordan Charbonneau Leave a comment

Red clover (Trifolium pratense) is an herbaceous biennial plant native to Europe that has naturalized throughout North America. While some consider red clover a weed, herbalists, and gardeners recognize its value. This beautiful plant is excellent for soil and human health. Here are some of the reasons we’re big fans of red clover and how we use it.

Red Clover as a Cover Crop

Red clover is a nitrogen-fixing cover crop. It’s an excellent choice for adding green manure to build up soils and a good nectar source for some pollinators. You can sow it in fallow fields, pathways, and small openings to help suppress weeds.

You can sow red clover in early spring, late summer, or fall as a winter cover crop. It can be a little slow to establish, so sow clovers at least 40 days before your average first frost.

Consider using buckwheat as a nurse crop if you’re sowing red clover during the hotter months. The clover will grow slowly under the buckwheat until fall frost kills the buckwheat, allowing the clover to establish quickly without the need for fall tilling.

Red Clover in Herbal Medicine

I’m not a doctor. This article is for informational purposes only. Consult a physician or clinical herbalist before using herbal remedies to treat any condition.

Herbalists have used red clover for centuries to treat a wide range of conditions, from menopause to whooping cough. Many of its uses revolved around female health. Modern science is beginning to explore the properties of plants, including red clover. While further research is needed, red clover tea and tincture may have a few potential benefits.

Benefits of Red Clover

Red clover contains phytoestrogens, which can mimic estrogen in the body.
Red clover may reduce osteoarthritis symptoms related to menopause. A 2015 study of 60 women found that taking red clover extract over 12 weeks reduced bone mineral density loss in the spine.
In another study of 109 postmenopausal women, participants reported skin and hair texture improvements after taking red clover extract for 90 days.

Further research is needed in all of these cases. Don’t use red clover if you have a hormone-sensitive condition like breast cancer.

Harvesting and Using Red Clover

Beyond its health benefits, red clover is also just an enjoyable herb to use. Both the leaves and the flowers are edible. Some of you may remember pulling the pink blossoms from the flowerhead and eating them as a kid.

The leaves, which have a mild bean-like flavor, can be added to salads. The blossoms, which are sweet, can be used in tea, baked goods, or salads. It’s best to break them up or pull the tubular flowers from the flowerhead, as whole flowerheads can be dry and tough to chew.

Harvest leaves and flowers that look fresh and are free from dried, brown spots. Remember to leave some blooms for the pollinators, especially if you’re harvesting from wild patches.

Red Clover Tea

Making red clover tea is simple: Pour about 2 cups of boiling water over about 1/4 to 1/2 cup of fresh or dried red clover blossoms and let it steep for 10 to 15 minutes. You can also let it cool and pour it over ice to make a fun summertime herbal iced tea.

Red clover mixes well with other flavors. Feel free to experiment with adding lemon balm, mint, white clover, chamomile, or orange slices to the mix and sweeten with honey or maple syrup to taste.

Red Clover Tincture

Using the folk method, you can make a basic red clover tincture with fresh or dried red clover blossoms. All you need is a few simple ingredients and some patience.

You simply place the blossoms in a glass jar and cover them with 80-proof alcohol. Then, keep the tincture somewhere dark for 2 to 6 weeks, shaking it once a day. After this period, you can strain it and begin using it.

Be sure to check out our complete instructions for Folk Method Tinctures.

Red clover is a fun herb to grow and use. Try growing it as a cover crop in your garden this season and enjoy its many soil health, culinary, and herbal benefits.

Garden Advice

Cover Crops: Improve Clay Soils

October 11, 2023 Jordan Charbonneau Leave a comment

Utisols, also known as red clay soils, are the most common soil type in the Southeastern United States. They’re what many Southern Exposure Seed Exchange customers and seed growers garden. While many gardeners may wish they had soft, dark loam, clay soils aren’t terrible. Like any soil, they come with their own set of advantages and disadvantages. In this post, we’ll discuss the features of clay soil and how you can use cover crops to improve it.

Advantages of Clay Soil

Clay soils aren’t perfect, but they come with their own set of advantages. Clay soil holds water for much longer than sandy soil, especially when you mulch it, helping you cut down on that water bill.

Clay soil is also high in nutrients and minerals that plants need, the perfect starting place for a garden. All of those tiny clay particles are also very good at holding onto nutrients from amendments that tend to leach out of sandy soil quickly.

While clay soils are dense, that density helps perennial plants and fruit trees hold tightly to the ground and withstand wind, storms, and erosion better than in light, sandy soil.

Disadvantages of Clay Soils

If you’ve ever had to till or dig garden beds in clay, you’re probably already familiar with one of the main disadvantages. Clay soil is heavy. This makes working it quite troublesome. When it’s wet, it’s heavy and sticky. When it’s dry, it’s often brick-like.

This same characteristic also means that clay soil compacts easily. Especially when the soil is wet, walking on it or using equipment on it can cause severe compaction. Heavy, dense clay soil can be especially tough to deal with if you’re hoping to grow root vegetables like carrots.

Some of its advantages can have a negative side, too. If you live in boggy or low areas, clay soil’s ability to hold water isn’t ideal and can lead to issues like root rot. Additionally, its ability to hold little particles also means that it can hold onto bad particles like salt, and changing the soil’s pH may take some serious work.

What Do Clay Soils Need?

The best thing you can do to amend clay soil is to add plenty of organic matter. There are many ways to add organic, including compost, mulch, leaf mold, peat moss, and cover crops.

Don’t add sand. It can be a tempting choice to improve drainage, but it gets stuck between the clay particles and creates denser, brick-like soil.

Though somewhat slow, cover crops are an excellent, affordable way to build up organic matter in the soil each season. They can help add nutrients and break up hard pans and compaction, allowing air and water into the soil.

Using Cover Crops to Improve Clay Soils

There are several great cover crops for improving clay soil, and fall is a great time to plant them! While all cover crops are good, some excel in specific areas.

Cover Crops to Add Organic Matter

Clover

Clover is an all-around good choice for cover cropping. Clovers fix nitrogen and produce plenty of organic matter. White Clover can be sown in late winter, spring, summer, or fall. It also makes an excellent living mulch for pathways. Mowing these paths and collecting the material with a bagger gives you a consistent supply of mulch and organic matter for the beds they border.

Winter Wheat

Though generally grown as a cereal, winter wheat is also an excellent cover crop. It produces a large amount of mulch material, adding plenty of organic matter to the soil. It’s also easy to kill and less likely to get weedy than other cover crops. It’s also a great cover crop for no-till systems. Mow it down in the spring and transplant it into the beds.

Buckwheat

Buckwheat is one of the fastest-growing cover crops. It can create tons of organic matter in just 30 to 45 days. We recommend sowing buckwheat with crimson clover for a fall or winter cover crop. The buckwheat acts as a nurse crop for the crimson clover during the heat of the day. In the fall, the buckwheat is killed by frost.

Cover Crops to Break Up Compacted Soil

Daikon Radishes

Daikon Radishes are popular for compacted soils because their tough, fast-growing roots easily break up the soil. They put on rapid fall growth, and winter kills them where temps regularly get below 20°F.

The crop residue from daikons decomposes quickly and releases its nitrogen early. The channels created by radish roots improve infiltration, drainage, soil warming, and growth of the next crop’s root systems.

Rye

Rye is a great winter cover crop with an extensive root system, making it an excellent choice for improving soil structure in compacted beds. Rye is very good at releasing phosphorus and potassium. It also stabilizes excess soil and manure nitrogen.

Many of us gardeners of the Southeast grow our crops in red clay soils. While we’re thankful for the nutrients and other advantages they bring, they also have a few downfalls. One of the most affordable ways to improve these soils is to grow cover crops. Choose one of these cover crops and sow this fall to improve your clay soil this winter.