What Are the Treatments for White & Gray Mold on Peas?

What is Powdery Mildew?

Powdery mildew is a type of fungus that spreads to plants through wind, water, contact with infected plants or even through pests. While no water is necessary for the fungus to develop, warm, dry weather in a humid climate is the most ideal setting for the fungal spores to germinate and overtake the plants. The disease spreads quickly, and each type of powdery mildew is specific to the plant it grows upon, meaning that the proper host plant must be available for the spores to survive and grow. Powdery mildew is identified by gray, white or yellow spots on the surface of the plant. The fungus may appear downy or dusty, even moldy.

Powdery mildew damages the peas it feeds on by inserting its root-like structures into the surface tissues of the plant. The result is leaf drop, leaf wilt, destroyed leaves, destroyed fruits and overall plant wilt or destruction. This fungus spreads rapidly and overtakes a plant, then overtakes any neighboring plants. If left untreated, the fungus may wipe out an entire crop of pea plants forcing a gardener to restart with a fresh crop of peas.

Chemical fungicide products applied to peas are effective at eliminating powdery mildew and preventing it from wiping out your crop. These products are available in garden supply stores. Choose a product formulated specifically for powdery mildew and that is labeled safe for use on pea plants. Follow label instructions exactly. Monitor your peas after treatment and reapply the product as many times as necessary to prevent further or re-infestation. Consider reapplying the treatment occasionally as a safeguard to prevent further incidents.

Baking soda sprays made of baking soda, vegetable oil, water and natural soap are effective at killing powdery mildew when sprayed onto affected pea plants. This type of treatment is safe for use around humans and animals, causing no harm if they are exposed to it or ingest plant leaves or fruits treated with it. Other alternative methods include removing infected plants from the garden and removing infected leaves, fruits or stems. Finally, practicing crop rotation (planting your peas in a different spot after each growing season) between plantings helps prevent powdery mildew problems.