Managing Flood Damaged Vegetable Gardens

After a flooding event, biological and chemical contamination is of concern for vegetables, fruits, and other edible crops. Chemical contamination includes pesticides, agricultural chemicals, heavy metals, and petroleum products. Biological contamination may include bacteria, parasites, and viruses such as E. coli, Listeria, Salmonella, and Norovirus originating from upstream farms, rural septic systems, sewage systems, and raw manure.  These contaminants pose a serious food safety risk.  Proper handling of garden produce after flooding is important.

Following a flood, the safest course of action is to discard all plants and produce from the garden.  

flooded garden By Kokhan O AdobeStockWhat Can be Salvaged?

In most cases, the plants and produce in the vegetable garden should be discarded.  Some steps can be taken to salvage produce that flood waters have not touched.  

  • Produce that remained above the flood waters and is not potentially contaminated could be eaten.  Before consuming, thoroughly clean and peel or cook the produce.
    • Thoroughly clean produce by rinsing with clean water, soaking in a mild bleach solution (2 tbsp per gallon of water) for at least two minutes, and rinsing again with cold tap water.
  • Any produce that was above the water but may have been splashed with flood waters should be destroyed.
  • Any produce from a flooded garden that is consumed raw should be discarded.  This includes leafy greens, melons, carrots, and radishes, among other things.
  • Any produce not fit for human consumption because of flooding should not be fed to animals, pets, or livestock.
  • Destroy any damaged produce that was in the garden during the flood event, including those with blemishes, cracks, or bruises.  
  • Washing, peeling, and cooking can help prevent the spread aerobic food-borne pathogens, but these practices do not destroy food-borne pathogens that have already contaminated the produce or destroy chemical or industrial contaminants. If you feel there could be such contamination in the water (even if the produce itself didn't touch flood waters), all produce should be discarded and plants destroyed. 

Give the Garden Some Time

Before harvesting any crop grown or planted in a recently flooded garden, there is a recommended waiting period.  Wait 90 days to harvest any produce that does not come in contact with the soil.  This includes crops like sweet corn, peppers, beans, or tomatoes growing on a support.  Wait 120 days to harvest any produce that does come in contact with the soil.  This includes things like vining crops (cucumbers, melons, etc.), root crops (carrots, beets, etc.), leafy greens (kale, lettuce, spinach, etc.), and untrellised tomatoes.  

Any produce in the garden that is harvested before this recommended waiting period should be discarded.

If the plant was growing during the flood but the produce matures after the recommended waiting period, it can be harvested.  Thoroughly wash before consuming.   

Perennial Edible Crops

All perennial edible crops can be harvested if done so after the recommended waiting period. 

  • 120 days for those that touch the soil, like asparagus, strawberries, and rhubarb 
  • 90 days for those that do not touch the soil, like raspberries and tree fruit

For most perennials crops, this means the harvest for that growing season has been lost.

Can I Replant?

Vegetable gardens destroyed by flooding can be replanted.  Several crops, such as radishes, leafy greens, broccoli, and peas, are successfully planted in late summer for fall harvest.  Other crops, like green beans, sweet corn, carrots, and beets, have relatively short production times.  More information can be found in this article: Vegetable Planting and Harvesting Times.

Gardens can be replanted provided the following conditions can be met:

  1. You can wait at least 30-60 days before replanting in flooded fields
  2. The produce will be harvested after the recommended waiting period (90 or 120 days) 
  3. The produce will mature before the average first frost date

If these conditions cannot be met, wait to replant until the next growing season. 

Alternatives to Replanting

Fresh local produce can be purchased at farmer's markets. Additionally, some vegetables could be grown in containers to replace what was lost.  More information can be found in this publication: Container Vegetable Gardening.

Plant a Cover Crop

Consider planting a cover crop for the remainder of the growing season.  A cover crop can help break up and introduce more air to oxygen-deprived soils and reduce the number of weeds that can take root.  For home gardeners, planting a cover crop that winter kills is best.  This could include oilseed radish, oats, yellow mustard, buckwheat, sorghum-sudangrass, cowpea, sunhemp, or buckwheat.

The Most Important Thing to Remember

Above all, when in doubt, throw it out. If you are unsure about the safety of any garden produce, remove and destroy all plants.

Additional Information

Related Information

Photo credit: Kokhan O/AdobeStock

Last reviewed:
June 2024