Skip to main content

One Bad Apple

M.Grabowski, UMN Extension Educator

Sunken black rings of fungal growth on a stored pumpkin
If you have stored garden produce from your own garden or the farmer's market be sure to regularly inspect this produce for problems. One bad apple spoils the barrel succinctly describes how post harvest rot organisms can start in one bad piece of fruit and grow to infect everything sharing the same storage bin. Fungi and bacteria can both cause rot of garden produce in storage. Some of these organisms are weak pathogens that infect the plant in the garden but do not cause damage until after harvest. Others, like common bread mold (Rhizopus sp.) and blue mold (Penicillium spp.) are saprophytes that can easily be found in soil or plant debris.

Post harvest rot organisms take advantage of wounds like small cuts, bruises, or chilling injury to infect plant tissue. To avoid problems with storage rot harvest fruits and vegetables when they are fully mature but not overripe. Take care not to bruise or damage the fruit during the harvest process and do not store produce that is already showing signs of rot or has obvious cuts or bruises.

White mold  spreads through stored carrots. W. Brow Jr. Bugwood
Store each kind of produce in ideal conditions for that fruit or vegetable. Regularly inspect stored produce for signs of rot. Look for small round sunken spots, discolored areas, or soft tissue. Any produce showing these symptoms should be promptly removed. If caught early, the infected area can often be cut out and the remaining healthy tissue can be cooked and eaten. If the rot has taken over the majority of the fruit, remove the rotten fruit as well as all of the fruit touching it. Discard any rotten produce and use the neighboring produce in cooking as soon as possible as it has been exposed to the rot organism and will not likely store for long.

Print Friendly and PDF