Marjorie, an avid pea lover and member of Girard Garden delves into a pea plot mystery that has plagued us all summer.
A number of gardeners have struggled to grow peas, but a few have succeeded. Here is a copious list of possible problems associated with growing them. I wondered if some gardeners might comment on what they’ve noticed and whether there are some commonalities between gardeners’ observations. Two summers ago, the entire cucumber crop in many plots was decimated within a few days by a beetle that literally sucked the life out the large and beautiful vines. I currently have a plague of black bugs on my kale. This is first! Gardening is and always will be a humbling experience!
This excerpt is taken from Harvest to Table.
Peas grow best in cool weather, but peas are not limited to spring planting. Late summer and fall planting can result in fall, winter, and early spring harvests in mild-winter regions. Peas are best grown on supports to keep them off the ground and away from many pests and diseases.
Pea growing problems with cures and controls:
Seedlings fail to emerge from soil or seedlings are eaten. Cabbage maggot is a small gray-white, legless worm to ⅓-inch long; adult looks like a housefly. Seedcorn maggot is a small, yellowish white maggot, the larva of a small gray fly. Flies lay eggs in the soil near the seedling or plant. Apply lime or wood ashes around the base of plants; time planting to avoid insect growth cycle. Plant a bit later when the weather is drier.
Plants are eaten or cut off near soil level. Cutworms are gray grubs ½- to ¾-inch long that can be found curled under the soil. They chew stems, roots, and leaves. Place a 3-inch paper collar around the stem of the plant. Keep the garden free of weeds; sprinkle wood ash around base of plants.
Seeds rot or seedlings collapse with dark water-soaked stems as soon as they appear.Damping off is a fungus that lives in the soil; it emerges where humidity is high. Do not plant in cold, moist soil. Make sure soil is well drained. Rotate crops.
Plants stunted; vines off-color; roots rotten or absent. Root rot and crown rot. Improve soil drainage by adding aged compost to planting bed. Destroy infected plants. Rotate crops. Plant resistant varieties.
Leaves curl under and become deformed and yellowish. Aphids are tiny, oval, and yellowish to greenish pear-shaped insects that colonize on the undersides of leaves. They leave behind sticky honeydew. Spray away aphids with a blast of water. Use insecticidal soap.
Leaves turn pale green, yellow, or brown; dusty silver webs on undersides of leaves and between vines. Spider mites suck plant juices causing stippling. Spray with water or use insecticidal soap or rotenone. Ladybugs and lacewings eat mites.
Trails and tunnels in leaves. Leafminer larvae tunnel inside leaves. Destroy infected leaves and cultivate the garden to destroy larvae and keep adult flies from laying eggs. Cover crops with floating row covers.
Holes chewed in leaves, leaves skeletonized; runners and young fruit scarred. Spotted cucumber beetle is greenish, yellowish, ¼ inch (7mm) long with black spots and black head. Striped cucumber beetle has wide black stripes on wing covers. Hand pick; mulch around plants; plant resistant varieties; dust with wood ashes.
Large holes in leaves; leaves skeletonized. Armyworms are dark green caterpillars the larvae of a mottled gray moth with a wingspan of 1½ inches. Armyworms mass and eat leaves, stems, and roots of many crops. Handpick caterpillars and destroy. Cultivate after harvest to expose the pupae. Use commercial traps with floral lures.
Semicircular notches on leaf margins; holes in blossoms. Pea weevil is a brownish beetle with white and black spots to about 1/5 inch long. It feeds at night. Sprinkle diatomaceous earth or wood ashes around plants. Spray with pyrethrum.
Scorched leaf margins. Molybdenum deficiency. Test soil. If deficient in molybdenum, add one teaspoon of ammonium molybdate per 1,000 square feet.
Round to angular spots on leaves, reddish brown to black. Anthracnose is a fungus disease that spreads in high humidity and rainfall. Leaves may wither and fall. Plant may die back. Generally found in eastern North America. Spray or dust with a fixed copper- or sulfur-based fungicide every 7 to 10 days. Remove and discard infected plants. Avoid working in the garden when it is wet which can result in spread of spores. Keep tools clean. Rotate crops.
Irregular yellowish to brownish spots on upper leaf surfaces; grayish powder or cottony mold on undersides; dark sports on pods. Downy mildew is caused by a fungus. Improve air circulation. Add aged compost to planting beds to improve drainage. Plant resistant varieties. Rotate crops. Keep garden free of plant debris. Use a 4-year rotation.
Round white powdery spots and coating on leaves, stems, and pods. Powdery mildew is caused by fungal spores. Spores germinate on dry leaf surfaces when humidity is high; spores do not germinate on wet leaves. Common in late summer or fall but does not result in loss of plant. Avoid water stress. Pick off infected leaves. Rotate crops. Keep water off foliage as much as possible. Destroy plant debris after harvest.
Lower leaves yellow; cross-section of lower part of stem may show reddish-orange discoloration; plants are stunted and yellow. Fusarium wilt is a fungal disease which infects plant vascular tissues. Fungal spores live in the soil and are carried by cucumber beetles. Plant resistant varieties. Rotate crops. Remove and destroy infected plants. Fungicides are not effective.
Mottled light and dark green pattern on leaves; leaves are distorted and may become brittle and easily broken; plants are stunted. Mosaic virus has no cure; it is spread from plant to plant by aphids and leafhoppers. Plant resistant varieties. Remove diseased plants. Remove broadleaf weeds that serve as virus reservoir. Infected plants can produce edible fruit but the size and yield is reduced.
Vine produce but few blossoms appear. Too much nitrogen. Pinch back growing tips to slow down green foliage growth and encourages flower production.
Pea blossoms are not followed by pods. Pollen is not reaching the female parts of the flower. Peas are self-pollinating; gently shaking plants during blossom period will aide the distribution of pollen.
Purple specks or lesions on leaves and pods. Ascochyta blight is a fungal disease that leaves streaks on stems; sunken tan or dark spots on pods. Remove and destroy infected plants. Apply sulfur as a fungicide. Plant resistant varieties.
Brown cavity on surface of pea. Manganese deficiency in alkaline soils. Spray the foliage with 1 percent manganese sulfate solution at flowering time and again 2 to 3 weeks later.
Cloudy cream or yellowish colored spots without definite margins on pod, tissue underneath is spongy. Stink bugs are gray or green shield-shaped bugs about ¼-inch long; they feed on fruits. Remove garden debris and weeds where bugs overwinter. Trap adults under boards and hand pick in the morning. Hand-pick egg masses and destroy.
Pods deformed; surface of pods scarred. Thrips are minute insects, yellow, brown, or black with narrow fringed wings; they scrape plant leaves and fruit as they feed. Keep garden free of weeds. Place diatomaceous earth around plants. Spray with insecticidal soap.
Plants are deformed; pods are highly deformed. Pea enation virus causes leaves to blister and become translucent. Plants and pods become deformed. Virus can not be cured. Virus is spread by aphids; control aphids. Plant resistant varieties.
Pods are woody. Harvest sooner, as soon as peas fill out but are still tender and succulent. Pods left on the vines too long will become hard and woody.
Plants stop producing pods; leaves turn yellow, then brown, and die. Hot weather; peas are cool-season vegetable. Plant early and heat-resistant varieties in warm regions.
Please comment here if you think one of these problems has been yours in growing peas, so we can better address this issue to develop a communal strategy.