As summer temperatures soar, so does the risk of heat stress to our plants. Our first instinct when we see our beloved hydrangea or hosta begin to wilt and turn black is to water it with cold water in an attempt to calm it down. But overwatering heat-stressed plants can actually do more harm than good.
When daytime temperatures rise above 85°F, our plants may begin to show signs of heat stress. They may begin to wilt, droop and the leaves may even show signs of sunburn. Heat-stressed plants are more susceptible to pests and diseases, so it’s important to treat this problem quickly before it develops into other issues.
The first step is to determine whether or not your plant is heat stressed (or if it just needs a drink). Then it’s time to take action and save your heat stressed plant without over watering it and creating a whole different set of problems.
What is heat stress?
Heat stress in plants occurs when temperatures rise above 85°F. Ideal growing conditions for most plants are between 60° and 85°F. So when temperatures reach above that and into the 90° to 100°F range and above, heat stress is a real concern.
Plants suffering from heat stress fall over, appear wilted, may show signs sunburnand may be delayed. Sunburn can occur on leaves or stems of plants. It looks like pale or discolored spots on your plant’s foliage and is caused by overexposure to bright sun.
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How to save heat-stressed plants
If you notice signs of heat stress in your plants while gardening during a heat wavedon’t worry There are a few simple steps you can take to save plants before it’s too late. But don’t rush the hose just yet, because excessive watering Heat-stressed plants can actually make the problem worse. Here’s what you should do.
1. Check your soil moisture
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Before drowning your plants with a big drink of water is best check your soil moisture level first. You can use the finger test to do this. Simply stick a finger about 1 inch (2.5 cm) into the soil to see if it feels moist. If it does, then lack of water is not the problem. If it doesn’t, then it’s probably time to give your garden a drink.
Another foolproof method is to use a soil moisture meter, like the one from Amazon. This type of device tells you exactly how much moisture is in your soil and whether or not your plant really needs more water.
THE the best time to water the plants it’s morning but if your plants are wilting and their soil is dry then you can water them at the base of the plant.
2. Add Mulch
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Whether your plant needs more water or not, it’s a good idea to add some mulch around your heat stressed plants regardless. One layer of one organic mulch, which you can order on Amazonretains moisture and keeps plant roots cool.
When temperatures are too high, the soil heats up just like the air and this causes the roots to heat up as well. This can cause heat stress to plants, but a layer of mulch helps reduce temperatures and adds organic matter and nutrients back to the soil as it breaks down over time.
3. Provide sun protection
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If you notice a sunburn or sunburn on your plantsthen it’s time to provide some shade. A simple one shade cloth, like this one from Amazonit can help protect plants the way sunscreen protects gardeners from the hot summer rays.
Creating shade for plants it will protect the foliage from burning and also help keep the plants cool. Think how refreshing it is to step under the shade of a tall oak on a hot summer day. Give your heat-stressed plants some respite from the blazing sun with a shade cloth.
If you are growing plants in containers, simply move them to a shadier part of your yard during the hottest part of the day. A covered patio is the perfect spot. You can use a Rolling plant caddy, like this one from Amazonto facilitate the movement of large planters.
4. Stop lubrication
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You might think that giving plants a boost in their favorite food will help them come out of heat stress stronger, but the opposite is true. Fertilizer it forces plants to promote new growth, which can further stress them. It can also cause sunburn on plant foliage, so lubrication in hot weather it’s a bad idea all around.
Conversely, if your plants show signs of heat stress, stop feeding them immediately. Allow them to rest and recover before adding more nutrients back into the soil.
5. Remove ripening fruit and faded flowers
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If the the plants in your vegetable garden are heat stressedthen it may be time for an early harvest. Edible plants work hard to send their energy into growing fruits and vegetables. But this can be at the expense of their own health and vitality.
If you want your plants to continue producing fruit and vegetables for the rest of the summer, you can harvest the products this is ripening now to give them a break and let them rest before sending the next round of fruit.
The same principle applies to flowers. If you leave faded flowers on your plants, they will work to send energy to produce viable seeds to the blooming inflorescences for reproduction. Deadhead flowers that flower to allow heat-stressed plants to focus on staying alive rather than producing seeds.
