Help Your Plants Escape the Heat

by Sandy Swegel

It’s hot hot hot here in Colorado and to make it worse, smoke from the wildfires out of control has caused local authorities to issue “stay indoors” advisories.  We’re all suffering, plants especially since they can’t get up and come inside away from the heat and particulate pollution.  How can we help our plants survive the heat when they are stressed?

Don’t overwater.  A little extra water is good now, especially since air humidity is almost nonexistent, but you can easily kill your plants with overwatering.  Droopy leaves can also mean intense air heat, not just lack of water in the soil.  Put your finger in the soil to see if it is really dry before you water again.

Recognize Heat Stress.  The easiest way to recognize heat stress in plants is to wait until after it is cool in the evening.  If the plant perks up and stands tall again, you have confirmation that the plant was droopy because it was trying to conserve water loss to evaporation.

Make Some Shade.  It can easily be 15 degrees cooler in the shade.  You can make some temporary shade for your plants with shade cloth, row cover or burlap.  If you have coffee roasting companies near you, they usually have lots of free burlap coffee bags.  Last year my neighbor had enough row cover for one section of peas.  Those peas produced for another two weeks, while the uncovered peas just went to seed.

Mist mid-day.  Another neighbor has magnificent salad greens throughout much of the summer and says it’s because she waters/mists every day at 1 pm.  Just like in the grocery produce section, little misters come on for two minutes and cool everything down.  Scientifically, I know that humidity is gone quickly and misting should only work if you do it every hour, but her greens are pretty amazing.

Be More Vigilant for Pests.  Any stress such as heat on a plant makes them more susceptible to pests.  Keep an eye out for more pests than usual.  Hosing aphids off gives the plant and the gardener a little more humidity.

Mulch, if needed.  A couple inches straw or grass clippings will hold water in the soil and cool the roots.  If you didn’t mulch earlier, now is a good time to start.

Check containers to see if they needed to be watered twice a day.

Protect the gardener.  Drinks lots of water.  Getting dehydrated is easy and the gardener needs a clear head so he/she can take care of the garden. Wear hats and sunscreen.  And now in Colorado, wear a dust mask to prevent inhaling too much smoke from fires 90 miles away.