Common Disease Problems
Anthracnose: This is a fungus that causes brown sunken spots that enlarge into round black spots with pinkish centers. Seeds turn yellow with rusty brown spots. The disease spreads with slashing water and can overwinter in the soil. Burpee Recommends: Rotate crops with plants in a different family. Do not handle plants when wet. Do not compost infected plants.
Common Bean Mosaic Virus: This virus causes mottled yellowish foliage with leaves that curl downwards. The plants are stunted and yields are reduced. The disease can be spread by aphids. Burpee Recommends: Remove infected plants and discard. Control aphids. Grow resistant varieties.
Downy Mildew: This fungus causes whitish grey patches on the undersides and eventually both sides of the leaves. Burpee Recommends: Rotate crops with plants in a different family. Avoid overhead watering. Provide adequate air circulation, do not overcrowd plants. Do not work around plants when they are wet.
Powdery Mildew: This fungus disease occurs on the top of the leaves in humid weather conditions. The leaves appear to have a whitish or greyish surface and may curl. Burpee Recommends: Avoid powdery mildew by providing good air circulation for the plants by good spacing and pruning. Contact your Cooperative Extension Service for fungicide recommendations.
Root Rot: This fungus causes damping off in seedlings, and in older plants, the leaves turn yellow and drop off, stunting occurs, pods and seeds are small and roots are discolored. The fungus can live in the soil for five years. Burpee Recommends: Rotate crops with plants in a different family. Consider planting in containers.
Common Pest and Cultural Problems
Aphids: Greenish, red, black or peach colored sucking insects can spread disease as they feed on the undersides of leaves. They leave a sticky residue on foliage that attracts ants. Burpee Recommends: Introduce or attract natural predators into your garden such as lady beetles and wasps who feed on aphids. You can also wash them off with a strong spray, or use an insecticidal soap.
Bean Beetle and Mexican Bean Beetle: The white larvae bore into roots and can also damage stems. The adult beetles are reddish orange, ¼ inches ling with 3-4 black spots on their backs. They chew holes in leaves from the underside. Mexican bean beetles look like copper colored lady bugs. Burpee Recommends: Hand pick. Remove plant debris. Check with your local Cooperative Extension Service for pesticide recommendations.
Cutworms: These insects cut off the seedlings at the soil level. Burpee Recommends: Place a paper cup collar (use a coffee cup with the bottom cut out) around the base of the plant. They are usually mostly a problem with young seedlings. You can also control by handpicking and controlling weeds, where they lay their eggs.
Leafhoppers: Leafhoppers cause injury to leaves and stunt growth. They also spread disease. Burpee Recommends: Remove plant debris. Use insecticidal soaps. Consult your Cooperative Extension Service for other insecticide recommendations.
Japanese Beetles: Burpee Recommends: Hand pick early in the morning into a bucket of soapy water.
What are inoculants? Inoculants are dormant bacteria safe to use with beans. Cowpeas, like other beans and peas, form a beneficial relationship with these bacteria commonly found in soil to capture nitrogen. Inoculants help beans planted in less than optimally warm or poor soils. New or heavily disturbed soils and soilless mixes need inoculants as they do not have a natural supply in the soil already.
Are your seed treated with inoculants or fungicides? No, we do not treat our seed with any products after harvest.
Why do I have no flowers on my plants? Too much fertilizer will make lots of leaves and no flowers. In the South, a pest called tarnished plant bug may inject a toxin into the plant that stops flower and pod production.
Why do my plants have flowers but no pods? Heat, moisture stress and a nutrient deficiency (usually phosphorus or calcium) or too much nitrogen can cause flowers to abort.
Can I start my cowpea plants indoors? We do not recommend starting cowpeas or any beans indoors. The plant roots are easily damaged when transplanting and beans grow so quickly that they do not need to be started early.