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Helping your garden through a heat wave

Rob Sproule, co-owner of Salisbury Greenhouse in Sherwood Park, says the recent heat wave and continuing hot temperatures near 30 degrees aren't great for most of our gardens and patio plants.
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Time to reassess the damage of a heat wave on your garden, says local garden expert. Photo: Metro Creative Connection

Rob Sproule, co-owner of Salisbury Greenhouse in Sherwood Park, says the recent heat wave and continuing hot temperatures near 30 degrees aren't great for most of our gardens and patio planters. During extreme heat conditions, Sproule says to keep a few key tips in mind:

Water deep - Don't just sprinkle the surface of your plants, put your finger in the dirt and feel how deep the dryness goes. Water should reach four to six inches deep, he advises.

Move your pots and containers - An easy fix. If you've got container plants, move them out of the direct, blazing sun and into a shady spot during a heat wave. Conditions in the shade are slightly better than in the blistering midday sun.

Water early or late - Forget about watering between 10 a.m. and 6 p.m., it's just too hot and water will mostly evaporate, says Sproule. Early morning is best, but later in the evening will do when temperatures are this hot, he says.

Don't stress your plants- Now is not the time to transplant or even fertilize your plants, says Sproule, as plants are directing all their energy to just surviving the heat. So water only, for now, and plenty of it.

Mulch - Mulch will help the soil around your plants retain moisture, says Sproule, so add straw or bark nuggets--about two inches worth. Don't add rock or landscape fabric though, these don't do well for retaining moisture.

Water foliage- In this heat, water on the leaves of plants is a good thing, and it can help keep aphids and spider mites off your plant leaves too.

After the heat wave, Sproule says to assess your plants. Some will be sunburned with brown marks, but they can return to health with lots of water. Even cool-loving plants like salad greens, pansies and snapdragons that look like toast are probably not toast, he says, and they can come back with--again--plenty of water. Heat-loving plants are loving these temperatures he says, so things like tomatoes, peppers, petunias, basil--they will thrive. Just keep the water coming.

"The good thing about this weather is, the slugs are gone. The bad thing is you'll have to catch up with lawn care and weeding once the weather moderates," he says. "Spider mites love the heat so spray your plants with the hose to blow the mites off. And if you have ants, turn the anthills over and pour boiling water in. That should take care of it."