Is the Produce from My Flooded Garden Safe?

News from Economic Development, Planning and Tourism, Posted on Thu, 08/20/2009 - 2:14pm

By Lynn Bliven, Cornell Cooperative Extension Association Team Coordinator

As a result of recent flooding, questions have been raised concerning the safety of consuming produce from gardens that were under water. There are two types of flooding. The first is more typical and occurs after a heavy downpour when a garden plot becomes saturated and water pools on the soil surface. This type of flooding may reduce yields and even kill plants but usually will not result in contamination of produce with human pathogens. The second type of flooding is more severe. When standing water remains in the garden or fields resulting from surface runoff or overflows from stream/river comprised of water that may have been contaminated with sewage, farm run-off, or environmental pollutants it is more likely be contaminated with human pathogens.

The following are recommendations taken from several sources including Cornell University, Michigan State University, Ohio State University, Texas A and M, Florida State University and U.S. Food and Drug Administration (FDA). Unless flooding was light and there is no danger of bacterial contamination from floodwater, do not use fruits and vegetables that were ready for harvest at the time of flooding.

The most conservative answer, the one that eliminates any and all risks, is to discard all produce that was covered by contaminated flood water. However, with weeks left in the growing season, you may wish to salvage some crops. Here are tips for considering what can be salvaged and what must be discarded from your flooded garden.

Some fruits and vegetables are more susceptible than others to bacterial contamination. All leafy vegetables (such as lettuce, cabbage, mustard, kale, collards, spinach, and Swiss chard) along with berries at or near harvest are more likely to be contaminated. Silt and other contaminants may be imbedded in the leaves, petioles, stems, or other natural openings of fleshy structures and can be difficult to remove. These should not be consumed as it's not possible to scrub these crops, and they have many ridges and crevices that could contain contaminated silt or bacteria.

Produce should be carefully examined before picking. If it is soft, cracked, bruised or otherwise blemished where contamination might have entered, throw it out. Root crops from "clean" flooding should be OK if the upper parts of the plants survive essentially undamaged.

Produce that will be cooked can be safely consumed in the short term. Begin by washing green beans, tomatoes, peppers, summer squash and other mid-to-late season crops in water. Do not use soap. Rinse with clear tap water and soak for 2 minutes in weak chlorine solution of 2 Tablespoons bleach to a gallon of water. Rinse in cool, clean tap water. Peel and cook thoroughly before eating. Change the bleach solution if you notice the water is no longer clean.

Root, bulb, and tuber crops such as beets, carrots, radishes, turnips, onions, and potatoes are less susceptible to bacterial contamination. Wash in water, rinse and sanitize as directed above. Peel and cook thoroughly before eating. Note: beets may be peeled after cooking, if desired.

Produce with a protected fruit or impervious outer skin such as peas, melons, eggplant, sweet corn, or winter squash may be contaminated on the surface. It is extremely important that produce be properly washed, rinsed and sanitized to reduce contamination. Melons and other fruits which will be eaten raw should not be consumed. Recent foodborne illness outbreaks linked to melons suggest that these low-acid fruits may not be safe even if surface-sanitized.

Flood-damaged garden produce that is otherwise unfit for eating – such as tomatoes that are cracked or decaying – should not be canned or otherwise preserved. Do not attempt to freeze or dehydrate these items.

Fresh produce from a flood-damaged garden may not be sold at a Farmers Markets or farm stands. According to the FDA: “if the edible portion of a crop is exposed to flood waters, it is considered adulterated and should not enter human food channels.”