Canadian wildfire smoke won’t hurt gardens

While many of us here in the Mohawk Valley are not experiencing the smoky conditions of last week, the Cornell Cooperative Extension of Oneida County’s Horticulture and Master Gardener Volunteer program would like to pass along some good news about your garden.  According to Steve Reiners, Professor Horticulture Section, School of Integrative Plant Science College of Ag and Life Sciences, Cornell University Cornell AgriTech, the smoke is more of a danger to you than your garden.

Canadian wildfires are affecting air quality here in the Northeast.  Smoke has filled the sky and warnings issued for outdoor activities. This is making many growers and gardeners worried about the potential impact the smoke will have on field-grown vegetables.  The good news is the impact will be minimal at worst.

Smoke-filled skies decrease sunlight and reduce photosynthesis, but to a small degree and temporarily. 

Despite the shade, there is still enough diffused light penetrating the smoke to maintain growth.  Smoke typically does not block the pores in the leaf (stomata) where photosynthesis happens.  The most important thing you can do is maintain good soil moisture by optimizing irrigation.  This will keep the pores open and clean.  The droughty conditions this spring are likely to cause more of a problem than the smoke.

Concerns that leafy greens and other commodities will pick up a smoky flavor are unwarranted.  Recent research done in California after wildfires there showed leafy greens had no issues with flavor or possible volatile chemicals on or within the leaves.  The smoke we are seeing does not contain dangerous chemicals.

The smoke we are experiencing is nearly 100% from the burning forests — not plastics, buildings or chemicals as seen in recent train derailments. The rain that falls through this smoky layer is also not dangerous to plants, people or animals.  Unlike acid rain that forms from the burning of high sulfur fuels, the rain will be near neutral pH or just slightly acid.

Pollinators will likely stay close to their hives when it’s smoky. 

It is a little early in the season for pollination of squash and other fruiting crops, so this should not be a problem.  Even if the crop has flowers, bees will become active again as soon as the smoke clears.

Mask up when you are outside tending to your plants, as the smoke is a danger to you and me.  However, the vegetables should be fine.  Keep them well watered, and you should be enjoying a normal harvest later this summer. Find the story here https://www.vegetables.cornell.edu/2023/06/09/smoke-not-a-problem-for-vegetables/

For more information on the Master Gardener Volunteer program or for garden questions call 736-3394 ext. 333 or email homeandgarden@cornell.edu.  Calls are answered weekdays from 8am-4pm.  Visit our Parker Scripture Botanical Gardens open daylight hours seven days a week.  The Butterfly House will open mid-July.