Why Do Strawberries Rot So Quickly?

Disease

• Bortrytis cinerea is a fungus that causes gray mold -- a widespread disease that affects strawberry plants. Although it can attack strawberries at any time, it's more common during periods of wet weather when plants are blooming and fruit formation occurs. Early-season symptoms often appear as blossom blight, but eventually lead to berry rot as the fungus travels throughout the plant. The disease is challenging to contain since damp weather enables fungal spores to travel from fruit to fruit and flower to flower until an entire patch is overtaken. Air flow between plants is a key requirement to controlling gray mold; circulating air enables plant's to dry out quicker. Spray plants with a fungicide in 10-day intervals beginning when new growth starts, and treat plants more often during bouts of frequent rain.

Heat

• Strawberries, even those ripening on the vine, become soft when temperatures rise, and extreme heat, 90 degrees Fahrenheit and higher, can cause strawberries to shrivel. If you don't intend to consume strawberries immediately, harvest them in the morning or late afternoon when temperatures are at their lowest and berries are still firm. Soft strawberries only last three to four days once picked because they bruise easily, which makes them highly vulnerable to decay.

Moisture

• Strawberries can't tolerate a lot of moisture without starting to rot. Moisture causes the berries to prematurely soften and lose their shape. Once a berry becomes soft, it's susceptible to injury. Soft strawberries also emit gases that cause them to decompose rapidly. Place plastic covering beneath strawberry plants to prevent berries from contacting the moist ground and decaying. Never wash picked strawberries until you're ready to eat them, and don't store them in a container that prevents air from circulating.

Prevention

• Only purchase a small number of strawberries a time, and consume them quickly. Inspect each strawberry thoroughly, and eliminate those that are bruised or soft. Discard moldy strawberries right away to prevent the fungus from spreading to other berries and fruit located nearby. Store unsliced strawberries in a cool, dry place, such as the refrigerator, uncovered until you're ready to eat them.