Cowpeas: How To Develop and Look after Black-Eyed Pea Crops

Cowpeas have a long history and are loved in many cultures. They originated in Africa, and in the southern US, it’s said they bring good luck if you eat them on New Year’s Day! Whether you eat them for luck or for flavor, you may want to plant this healthy crop in your garden.

These drought-tolerant “peas” are a sun-loving crop you can grow through the summer. They’ll add nitrogen to your soil and produce beans all summer long. There are different varieties to choose from, so feel free to experiment to figure out which kind you like best!

Let’s take a look at how to grow cowpeas so you can add them to your garden!

Quick Care Guide

All About Cowpeas

Cowpeas are beans are grown worldwide, primarily used for their seeds and for improving soil health.

You probably know Vigna unguiculata subsp. unguiculata as cowpeas or black-eyed peas. They’re actually beans – not peas – but most other nicknames for this plant refer to them as peas. They were first grown in west Africa but are now grown in many places throughout the world. In the US, they’re associated with the southern states because they need a long, warm growing season.

Cowpeas come in bush and vine varieties. Bush plants typically grow 1-2 feet tall, and vining varieties can reach around 3 feet. Bean pods grow in clusters of 2-3 and can reach up to 10 inches long. The pods can come in a variety of colors, including green, purple, or yellow. 

The kidney-shaped beans can be white, cream, green, black, or red-brown, or a mix of these colors. They often have a darker color in the middle to create an eye, hence the “black-eyed pea” name.

Cowpeas are a southern pea usually grown for the seeds, but the pods and leaves can also be cooked and eaten. They’re also grown in summer cover crop mixtures to improve soil health and soil tilth, or they’re grown as fodder for animals. Worldwide production of cowpea varieties tops out at millions of tons annually.

Types of Cowpeas

Vigna unguiculata has edible catjang and yardlong bean varieties, along with subsp. textilis.

Vigna unguiculata contains a few different varieties of beans. Subsp. biflora is catjang or sow-pea, which is known for its shrubby growth habit. Though it’s often grown as fodder for animals, it’s edible and delicious. These beans are also useful as cover crops.

Subsp. sesquipedalis is known as the yardlong bean, asparagus bean, and Chinese long-bean. It gets its name from being long; pods can grow up to 3 feet, although they’re usually 1.5 feet. This variety is believed to have originated from southeast Asia.

The cowpea cultivar subsp. textilis isn’t as popular these days, but it was once used for its fibers to make rope and fabrics. These beans can also be great cover crops for improving soil health and weed control too. 

Planting Cowpeas

Plant cowpea seeds outdoors in warm, well-draining soil with direct sunlight, 1-2 inches deep.

Cowpeas need warm weather and don’t transplant well, so you’ll need to sow dried peas outside after the danger of frost has passed and the soil temperature is consistently above 65°F. The time of year for your cowpea planting will vary depending on where you live, but it will likely be between April and June.

The video above walks through several methods of growing beans vertically.

Plant your cowpea seed in an area with well-draining soil that will get direct sunlight for at least 6 hours. Plant the seeds with the eye facing down 1-2 inches deep with no more than 8 plants per 1 foot in a row and 30 inches between rows. Cowpeas grow well in containers with trellises, so you’re not just limited to the ground!

A cowpea planting that includes succession planting will allow you to get a continual harvest rather than getting most of your beans at once.

Plant seeds outside every two weeks during the planting season so you can stagger the plants. You can interplant them among other crops that are good companions, like pearl millet or wheat.

Caring For Cowpeas

Cowpeas grow pretty easily if you give them enough sunlight. Let’s look at how you can make these “peas” happy and have quick growth!

Sun and Temperature

Cowpeas need warm weather and 6-8 hours of direct sunlight.

Like other beans, cowpeas need lots of sunny weather and only grow in the warm season. They can be grown in USDA zones 5-10 and can only be grown as perennials in zones 7-10.

They need a bare minimum of 6 hours of direct light, but if you can provide them with 8 hours or more, you’ll get better results and higher yields.

Soil temperatures should be 65°F or warmer, but avoid letting it get too hot, or the plants won’t set pods anymore. If the soil temperature goes over 90°F, consider using a shade cloth during the hottest part of the day.

Water and Humidity

To promote deep root growth, water cowpeas when the soil is dry.

Cowpeas need a little higher moisture than some crops do, with at least 1 inch of water per week, and will likely need more on hotter days. Water your cowpeas when the soil is dry, and give them a good soak to encourage deep root growth. 

Avoid getting their leaves wet or letting the water form puddles to prevent diseases. Be sure to monitor the soil moisture of your crops so the plants don’t get too wet or dry.

Soil

Cowpea plants require neutral or slightly alkaline soil that’s well-draining and nutrient-rich.

Cowpea plants like nutrient-rich soil with a neutral or slightly alkaline pH. Make sure the soil has a pH of 6.0 or higher, or your cowpea plant won’t be happy with the acidity.

The soil needs to be well-draining, so it won’t hang onto too much moisture. Loamy or slightly sandy soil will work well for cowpeas.

If you can provide your plants with plenty of organic materials, like compost, from the start, you may not need to fertilize your plants at all.

Fertilizing Cowpeas

Limit nitrogen fertilizer on cowpeas, as this can lead to more leaves and fewer beans.

Cowpeas are nitrogen-fixing, meaning they create nitrogen and return it to the soil. If you fertilize your cowpeas, avoid giving them too much nitrogen, or they’ll grow too many leaves and not enough beans!

As mentioned in the last section, you may not have to fertilize your plants at all if there are enough nutrients in the soil from organic matter. If your soil lacks nutrients, however, you can feed your plants an all-purpose fertilizer that’s low in nitrogen, like a 5-10-10 or 3-5-5 fertilizer. You’ll probably only need to fertilize them once when they’re young since they aren’t heavy feeders.

Pruning & Training Cowpeas

You can remove damaged parts of cowpea plants and support vining cowpeas with trellises.

Pruning isn’t necessary for cowpeas, but you can remove damaged or diseased leaves and stems. If leaves are touching the ground and look sickly, removing them will prevent the disease from spreading.

Vining cowpeas will need to be supported by a trellis or other kind of support. Bush varieties can also benefit from a trellis, but they won’t need it like the vining kinds do.

Cowpea Propagation

Cowpeas are typically grown as annuals, and planting seeds is the most effective propagation method.

The tried-and-true method of planting cowpea seeds is really the only propagation method you’ll need, especially since they’re typically grown as annual plants in most areas. Allow a few pods to dry on the plant. Harvest the dried seeds and save them to plant next year.

Harvesting and Storing Cowpeas

Now, for the important part: getting the cowpeas onto your plate! There are a few different ways you can harvest and store your beans (or peas).

Harvesting Cowpeas

Harvest cowpeas when the pods are 6-10 inches long, either immature or dry.

You can choose to harvest green pods (which are actually immature pods) or wait until all the beans are dry on the plant. You could even harvest somewhere in between.

Cowpeas are ready when the pods are 6-10 inches long, firm, and green. You can pick the pods right off the plant or cut them with scissors.

If you want to wait until the beans are dry, you can leave them on the plant until every pod is dried. Then, cut the plant at the base and hang the plant upside down for a few days to make sure they’re definitely dry. Remove the seeds from the seed pods and store them.

Storing Cowpeas

Store dried cowpeas in an airtight container in a cool, dry place.

Dried beans (technically dry seed) should be stored in an airtight container in a cool, dry place. Make sure moisture can’t get to the beans, or you’ll risk getting them moldy.

If you pick the pods while they’re green, you can store them in containers or freezer bags in the freezer for a few months. Make sure the beans don’t have excess moisture on them so they won’t turn into an ice block. You can also store cooked cowpeas in a similar manner and they should also be able to last for a few months.

Troubleshooting

You may have some problems while growing cowpeas, so let’s talk about them! Many of them can be prevented if you know what to look out for.

Growing Problems

Check soil temperature, adjust moisture levels, and avoid excess nitrogen from previous crops.

There are many reasons why your cowpea plants don’t produce pods. First, check the soil temperature. Temperatures below 65°F or above 90°F aren’t ideal and are likely to cause the plants to stop producing pods. Frost covers and shade covers can help you correct the temperatures. 

If the soil temperature isn’t the problem, check the water situation. Soil that’s too dry or wet can cause many problems and stress out the plant. Adjust moisture levels as needed.

Too much nitrogen could be a problem if you’ve grown legumes in the same spot as cowpeas within the last three years or if you gave your plants too much fertilizer this year. You can soak up nitrogen by planting leafy greens between your beans and adding a layer of wood chip mulch. Rotate your beans with other crops each year to prevent nitrogen from building up.

Pests

Mexican bean beetles are a common pest that can damage and destroy bean plants.

The most common pest found on cowpeas is the cowpea curculio. Adults feed on pods and seeds, which ruin the crops. They also lay their eggs inside the pods, and the larvae will eat their way out. 

Prevention is key – get rid of the adults before they lay eggs! It’s common to spray insecticides as a preventative measure. For a natural approach, try removing them by hand or spraying neem oil to suffocate them. Encourage beneficial insects that eat the curculio (like tachinid flies) by planting yarrow, asters, feverfew, and oxeye daisy. 

Other pests you might encounter like to suck sap from leaves, stems, and pods. Mexican bean beetles and bean leaf beetles are likely to be around for the legumes, while aphids and green stink bugs will be attracted by other plants but feast on cowpeas just because they can.

Most of these pests can easily be removed with water or by hand, and neem oil is also pretty effective. You can also look for insecticides that will target specific pests.

Cornstalk borers will only be present if you also have corn planted, so planting cowpeas and corn away from each other will help. Weevils are only a storage problem and can be avoided by using an airtight container.

Disadvantageous nematodes cause nodules on roots and yellowing and wilting foliage. Beneficial nematodes can be added to the soil to kill the nematodes. You can also remove roots from old plants and add organic matter to the soil to help reduce the population.

Diseases

The mosaic virus can cause stunted growth and reduced yields in cowpeas plants.

Most diseases cowpeas get can’t be reversed, but they can be prevented. Once a plant is diseased, it’s best to remove the plant to prevent it from spreading. You can prevent fungal diseases with a fungicide spray and prevent most diseases by keeping the pest population under control.

Common diseases that can easily be identified on the leaves are powdery mildew (white powder), rust fungus (red-brown spots), cercospora leaf spot (brown spots), and mosaic virus (mottled yellow and green leaves). Fusarium wilt looks like the plant is dying with wilted crunchy leaves. This can cause root rot in your crowder pea crops.

Bacterial canker is a goopy-looking lump commonly found on fruit trees, but can sometimes appear on a cowpea plant. Southern stem blight is a fungus that attacks the stem just below the soil line and can also affect every part of the plant that touches the soil.

Frequently Asked Questions

Q: What is the difference between cowpeas and black-eyed peas?

A: Black-eyed peas are cowpeas, and are called that because they look like they have a black eye. However, not every cowpea is a black-eyed pea since some are one solid color.

Q: What are cowpeas used for?

A: Cowpeas are used in cooking or as animal fodder.

Q: Why are they called cowpeas?

A: It’s believed that they earned their name due to them often being grown to feed cows and they have been used as early as 1798!

Q: Are cowpeas edible?

A: Yes! The seeds, pods, and leaves are edible, but you’ll want to cook the leaves first.

Q: What do cowpeas taste like?

A: Cowpeas have an earthy flavor that’s a bit nutty.

Q: What’s the difference between cowpeas and peas?

A: Cowpeas are actually beans, and beans and peas are both legumes, so they share many similarities.

Q: Are cowpeas and field peas the same?

A: Field peas are just another name for cowpeas.

Q: Do cowpeas add nitrogen to soil?

A: Cowpeas are a legume, so they add nitrogen to the soil. They can be used as a cover crop to improve soil quality and reduce weed pressure.