CORVALLIS, Ore. — Fruits and vegetables in gardens dusted with wildfire ash are generally safe to eat with proper cleaning, according to Oregon State University Extension Service experts.
“If your garden has a heavy layer of ash or is located near a structure that burned, the risk is higher. Burning buildings contain different toxins than a forest.”
Rinsing produce outdoors and then again in the kitchen sink helps remove ash and fine particulates, said Brooke Edmunds, associate professor and Extension community horticulturist in the OSU College of Agricultural Sciences.
Ash and smoke are unlikely to penetrate intact fruits and vegetables, she said, but risk increases the closer a garden is to a fire.
“Use your best judgment,” Edmunds said. “If your garden has a heavy layer of ash or is located near a structure that burned, the risk is higher. Burning buildings contain different toxins than a forest.”
In addition to rinsing, Edmunds recommends:
- Peeling produce like tomatoes, apples and root crops.
- Stripping outer leaves from lettuces and other greens.
- Soaking produce in a 10% white vinegar solution (1 cup vinegar to 9 cups water) for thorough cleaning.
This vinegar solution helps lift soil particles from vegetables like kale, Swiss chard and savoy cabbage, as well as fruits such as peaches, apricots and nectarines.
Protect yourself during harvest
Avoid harvesting while smoke lingers. When air quality improves:
- Wear a mask (an N95 is best; a cloth mask with a filter is a backup).
- Check current air conditions at AirNow.
- Remove shoes outside to avoid tracking ash indoors.
- Change and launder clothes immediately after coming inside.
- Wash hands thoroughly.
Food safety if fire moves close
If wildfire approaches your home, additional precautions are needed, as smoke and fumes can infiltrate even sealed buildings.
OSU Extension food safety experts recommend replacing:
- Food stored at room temperature, including potatoes, fresh produce and dried fruit in open containers.
- Refrigerated and frozen foods that show off odors or flavors.
- Canned goods exposed to temperatures over 95 degrees, or cans that are split, bulging or damaged.
Commercially sealed, undamaged metal cans may be disinfected and reused:
- Scrub with detergent.
- Submerge in a bleach solution (1 cup bleach to 5 gallons water).
- Label cans after disinfection.
Find more information at Food Safety and Wildfires from the Western Regional Center to Enhance Food Safety in the College of Agricultural Sciences.
Soil contamination concerns
The closer a garden is to a fire, the greater the possibility of soil contamination, Edmunds said. Gardeners may wish to test soil before planting again in spring.
Collect samples from multiple locations, label each sample by site and send them to a lab. The OSU Extension publication Get actionable results from a soil, plant or environmental testing lab is a helpful resource.
Ask the lab for heavy metals analysis that includes:
- Lead
- Cadmium
- Arsenic
- Nickel
- Mercury
Mapping soil sampling locations helps identify problem areas if further testing is needed.
Additional garden care steps
Other recommended actions include:
- Hosing ash off plants.
- Applying mulch.
- Using drip irrigation or soaker hoses to prevent soil splash.
- Using landscape fabric or weed cloth as a barrier.
- Avoiding soil disturbance.
- Never using a leaf blower to clean ash, which can cause dangerous inhalation.
If ash accumulation is thick, adding compost or clean bagged soil may help restore soil biology. However, amendments are not necessary for most gardens.
Previously titled Take precautions when wildfire ash falls on fruits and vegetables
