There are many indications that climate change is upon us, and the crippling heat waves taking place across the globe is one of them. The Center for Climate and Energy Solutions says our days will only be getting hotter; if greenhouse gas emissions aren’t significantly reduced by midcentury, scientists expect 20 record highs for every record low. Extreme temperatures can have a devastating impact on the garden, so we’ve put together a list of 5 cool ways to help your plants beat the heat!
1. Palm Fronds
In dry climates where temperatures hit the triple digits, tomatoes experience leaf drop, eggplants stop flowering, and the squash develops only male flowers, so they don’t waste energy bearing fruit. Garden Culture Magazine did a feature on Faultline Farm near California’s Mojave desert where the gardens consistently battle daytime temperatures of up to 115°F (46°C) in the summer. The lead horticulturalist at the time, Giavanna Accurso, told us about a neat idea she had to shade her crops from the heat with palm fronds eventually! At Faultline Farm, the fronds also double as barriers to keep the coyotes at bay.
2. Shade Cloth
If you live in a climate where palm fronds aren’t at your disposal, there are plenty of manmade materials available to keep the garden cool. From something as simple as a patio umbrella or an old bedsheet to more elaborate shade cloths designed explicitly for vegetable gardening, these are all easy and affordable ways to give your plants a break from the blistering heat so they can deliver the yields you crave.
Adding mulch to the garden at the beginning of every growing season is an excellent way to conserve soil moisture and control its temperature during periods of drought. When it gets scorching hot, mulch will spare you the second watering per day. Less frequent watering also means nutrients will stay put rather than washing out. And plenty of nutrients there will be; applying mulch in the spring before the soil begins to dry out will lead to a steady supply of organic matter broken down by microorganisms throughout the summer. Fine mulches such as shredded hardwood and leaves, pine fines, and compost should be applied around the plant (but not right up against the stem) at a depth of 2 inches; coarse mulches, such as straw or wood chips need thicker applications of about 6 inches.
4. Insulating Containers
A trick to keeping the soil cool in container gardens is to insulate the flower pots with newspaper or another kind of mulch. Insulating the pot helps plants stay cool in the heat by partially blocking the sun’s rays, but it will also keep them warm if temperatures dip. Select a pot about 3 inches larger in diameter than the plant’s primary pot. Once you’ve set the pot inside the larger one, fill the space between the containers with straw, leaves, newspaper, or any other kind of mulch. You can also add a couple of inches of leaves or bark to the soil surface for added protection.
5. Choose Plants Carefully
We might all soon be doing a little xeriscaping; a gardening technique focused on water conservation and the selection of drought-tolerant plants. While succulents are always a good option, there are many trees, shrubs, and even flowers that don’t need a lot of water and can withstand the heat very well. Artichokes, wormwood, fountain grasses, and geraniums are all excellent choices. Coneflowers, globe thistle, lavender, and iris can also survive with little moisture. Selecting plant varieties like these will not only save on water; it’ll also spare you a whole bunch of maintenance on those sweltering days. You’re welcome!