Help your garden cope with wildfire smoke

Ash and residue from wildfire smoke collects on rose leaves in Sacramento. Rinse it off to help plants cope. (Photo: Debbie Arrington)

Rinse off foliage to remove residue; wash veggies and fruit carefully

By Debbie Arrington

When you can see the air, stay indoors. 

Smoke from the raging Camp Fire burning near Chico continues to fill the Sacramento Valley. According to the Sacramento Region Spare the Air forecast, Sacramento and Yolo counties will be 184 on the Air Quality Index on Monday; 174 is predicted for Tuesday. Anything above 150 is considered unhealthy.

It was worse, particularly in some areas of concentration. A few are surprising. Rio Vista hit 247 at 6 a.m. Monday, according to the air quality districts. At that same time, Arden-Arcade reached 236; downtown Sacramento was 206.

A breeze blew out some of the smoke, but those winds have calmed significantly; good for fire fighting, but not for air quality. Expect this smoke to linger.

The smoke cover dropped daytime temperatures an estimated 10 to 12 degrees from the original forecast. Besides smoky, weather continues to be extremely dry with no rain forecast for at least another week.

When you do go out to your garden, concentrate on hydration. Wash off plant leaves where ash and other particulate matter may have accumulated. Deep-water shrubs and evergreen trees that need a drink.

Plants deal with smoke better than people. They "breathe" carbon dioxide and help purify the air. Our gardens now are doing double duty as smoke filters.

It's the particulate matter in smoke that becomes problematic. It clogs leaf stomata (or pores) and hampers this cleansing process. This residue can coat the outside of vegetables and fruit, too.

To remove that residue, spray plants with water, preferably early in the morning so leaves have a chance to dry. 

Are veggies and fruit exposed to smoke safe to eat? In most cases, yes. Grapes and tomatoes, which tend to be most smoke-sensitive, are already harvested. It's the apples, persimmons and leafy greens that are a concern now.

Ash forms a gritty coating on fruit and vegetables that tends to stick to skin and leaves. That smoky residue may be scrubbed off with water and a little dish soap, then rinsed and dried. For leafy greens, submerge completely in a basin filled with water and a teaspoon of soap, scrub, rinse and pat dry. 

If working around ash, wear protective clothing such as long sleeves, long pants, gloves, goggles and a face mask, recommend UC Cooperative Extension master gardeners. If ash gets on your skin, wash off promptly.

Don't use leafblowers for ash removal. It just puts it back into the air.