Heavy rainfall followed by flooding in early July had a devastating impact on communities throughout the Northeast. Not only were buildings, roadways and bridges damaged, but vegetable gardens were impacted as well, leading many home and community gardeners to ask “Are my vegetables, berries and edible flowers still safe to eat?”
The answer is “It depends.”
If your yard did not flood, and the soil in your garden is just saturated from rainwater, your produce is fine to consume. Plants that took a beating from all the rain should bounce back in well-drained soil.
However, if any edible parts of vegetables and berries or edible perennials came into contact with floodwaters, either above or below ground, do not consume. Edible parts include fruit, stems, roots, berries and foliage.
Because floodwaters likely contained debris, household and hazardous waste, heavy metals, chemicals and other contaminants. Or there could be disease-causing bacteria, viruses and parasites from raw sewage and animal manure. Any garden crops that have been submerged or splashed by floodwaters are considered adulterated and should be discarded in the landfill or tilled under to avoid food-borne illnesses.
Note that cooking does not eliminate the risk posed by industrial pollutants. And do not attempt to make produce from an unsafe, flooded garden safe by using chlorine bleach.
The safest option for flooded gardens is to till to a depth of at least six inches, adding in compost to increase tilth and dilute contaminants. Then plant cover crops, such as winter rye or oats, to speed the decline of pathogens before replanting next season.
However, if you are considering replanting this year, wait at least 30 to 60 days, and then weigh the health risks of replanting certain crops. For example, leafy greens, melons, cucumbers, root crops typically consumed raw (such as carrots and radishes) and other crops that have direct contact with flooded soils are at a much higher risk from microbial contaminants than crops with no direct contact with the soil.
Before replanting, have your soil tested for heavy metals by a certified lab. If results show no or very low levels of lead and heavy metals, your soil is safe for gardening. If levels are elevated, follow practices such as maintaining a high pH, adding organic matter or not growing certain crops. Or install raised beds or relocate the garden.
Tall, upright crops, such as tomatoes, corn and pole beans, where only portions of the plants were touched by floodwaters, are considered safe to eat, providing that they were not splashed by floodwater or touched by silt. For vegetables and edible plants that had no fruit or flowers when flooded, carefully weigh the risks of harvesting or not, based on your comfort level and the growth stage of the individual garden plants.
For brambles and blueberries, do not consume fruits that came in contact with floodwater. Flooded edible perennials, such as rhubarb, asparagus and herbs, should be cut down and not harvested again until next year. If you decide to keep flooded garden plants where edible parts have not yet developed, remove all flowers and immature fruit touched by floodwaters.
Discard any plants or plant parts that are cracked, bruised or blemished. Thoroughly wash the silt off each plant and provide a barrier, such as straw, black plastic or other mulch, to prevent splashing and dust from silted soils.
What about raised beds?
If floodwater did not come in contact with the plants, they are likely safe to harvest. A few exceptions are root crops such as potatoes and carrots where floodwater may have permeated the bed from the ground up and edible portions of crops that lie on the soil surface, including leafy greens, strawberries and melons, that came in contact with contaminated floodwater or soil. In both instances, discard the crops.
To salvage your garden, avoid walking on waterlogged soils to prevent compaction and additional root damage. If you have standing water, drain the area by redirecting the water from your plants by creating ditches or furrows. Although compacted soils can be aerated, wait until they are dry before working them to help maintain good soil structure.
Once dry, till if needed or aerate the soil with a garden fork by inserting it straight down into the soil about six inches deep about every 12 inches throughout the affected area.
If you have questions, contact the UVM Extension Master Gardener Helpline at https://go.uvm.edu/gardeninghelp. Or check out “Flood-Recovery Guidance for Lawns and Gardens” (https://go.uvm.edu/lawngardenfloodrecovery) and “After the Flood: Tips on Edible Garden Plants” (https://go.uvm.edu/after-the-flood).
Featured photo: Produce from gardens saturated from rainwater, but not flooded, is safe to eat although gardeners should avoid walking on waterlogged soils until dry to prevent compaction and additional root damage. Photo courtesy of Gustavo Fring/Pexels