Gardening in the Heat
by Rob Sproule
When the summer mercury rises, it’s not just humans and pets who get uncomfortable. Heat waves bring a lot of stress to gardens, but there are easy things that you can do (and avoid doing) to help your plants beat the heat.
If possible, try to water first thing in the morning. It can seem like a chore, but a walk around the garden before heading to work can really clear the head! An early drink will keep the soil cool as the mercury rises.
If morning aren’t an option for you, the next best time to water is in the evening, after the scorch has soothed. This isn’t a great idea when we have cold nights or mildew may set in.
Avoid overhead watering in the afternoon heat. It’s a pet peeve of mine to see water being launched 20 feet into the air by sprinklers at 4pm on a hot day. Not only is it highly wasteful, but it’s expensive, as well. If you water during the day’s heat, invest in a soaker hose that keep the water low to the ground.
Just like you don’t want to go do push-ups all day in 30 degree heat, your plants don’t want to be stressed out, either. Avoid “surgical” tasks like planting and transplanting until it cools off a little. Root systems work overtime in heat and don’t need any extra disturbances.
Try to water first
Plants have different types of root systems depending on where they come from. Native and/or cool climate plants tend to have deeper roots and are therefore better equipped to handle dry conditions. Tropical plants, like tomatoes, peppers, and many annuals, have roots close to the surface. Try to give them a little extra water, or when the soil dries and hardens it could damage the roots.
Cooling the Soil
Dark soil absorbs heat like a sponge, and hot soil can be dangerous to the roots just under the surface. Cool off the soil by adding mulch around heat sensitive plants like salad greens, root crops, and pansies. Cedar mulch or straw is best; avoid rock because it will heat up and actually make the problem worse.
Keep your lawn a little longer in the heat. Longer blades (around 3″) will both keep the roots cool by shading the soil and more leafy tissue means more ability to transpire, which helps cool the plant.