How to Rescue Heat-Stressed Plants Without Overwatering Them

This summer has been long, hot, and dry, and it’s taken a toll on my garden. So many of my plants are drooping, discoloring, and have stopped growing – all common signs of heat stress. The good news is there’s still time to revive them before colder fall conditions arrive.

If your garden has also taken a hit from the high summer temperatures, you might spot similar symptoms of heat stress. It can be easy to assume chucking a load of water on your plants will fix them, but this isn’t always what your plants need. In fact, plants can still droop and curl when the soil is sufficiently moist (which you can check with this soil moisture meter from Amazon), rather reacting this way to protect themselves from the sun. This is where other solutions are needed, like mulching.

So, to help you water plants in hot weather correctly and rescue heat-stressed plants without overwatering them, I spoke to a gardening pro for advice.

Always Check the Soil

Large garden borders in summer, with purple lupins, copper-purple beech hedging and lush, green perennial planting

‘Don’t assume that just because a plant is wilted, it needs more water,’ says Lindsey Chastain, homesteader and founder at The Waddle and Cluck.

‘When it gets really hot outside, plants will naturally wilt because they are trying to decrease the surface area that the sun has access to beat down on. They do that by curling their leaves in or drooping the blooms, and that doesn’t necessarily mean that it needs more water,’ she explains.

For this reason, you should first check your soil when you notice that your plants are looking stressed. You can use a soil moisture meter (also available from Walmart) to identify just how wet the soil is, or if it is bone dry and needs watering.

‘If the soil is still wet, then the plant doesn’t need water. It’s just trying to protect itself,’ Lindsey notes.

If you do need to water your plants to rehydrate them, Lindsey says it’s best to do so early in the morning and use the deep watering method.

‘Water at the base of your plant early in the morning before it gets too hot. Any water that is left on leaves or blooms, those droplets, turn into magnifying glasses for the sun, and they can burn your plants,’ she advises.

You may find a soaker hose (like this from Amazon) or a drip irrigation system (the Garden In Minutes watering grids are highly rated) make it more convenient to give your plants a thorough watering.

Lindsey Chastain

Lindsey Chastain, a dedicated homesteader and skilled writer, is the driving force behind The Waddle and Cluck, a platform that celebrates sustainable living, gardening, and responsible farming

Provide Mulch and Shade

To help rescue heat-stressed plants without overwatering them, you should focus on using moisture-retentive methods – including mulching.

‘Mulch a little bit more deeply when it’s super hot outside because that mulch will help retain moisture in the soil,’ Lindsey says.

There are lots of types of mulch you can use, like this brown mulch from Lowe’s. You can make leaf mulch or even use these mulching mats for trees from Amazon.

Garden shade will also reduce evaporation and protect foliage from leaf scorch.

‘If you can, move a stressed plant to a shaded area, this is a lot easier if your plants are in pots. If they are planted in the ground, you can put up some temporary shade with a canopy,’ Lindsey advises. ‘I’ve even used a couple of lawn chairs with a bed sheet draped over them just to give some plants a little bit of shade. You don’t want to completely block the light, but adding some shade for that afternoon heat wave can definitely help,’ she adds.

You can purchase 50% garden shade cloths (like this from Amazon) to put over plants in a more permanent position.

Avoid Pruning and Fertilizing

When plants are experiencing heat stress, they are weak and susceptible to further damage. For this reason, it’s best to avoid pruning and fertilizing, Lindsey notes.

‘Don’t go crazy with cutting off leaves that look damaged. They may still be leaves that are good. They are just stressed from the heat, so I would avoid pruning anything that is not very clearly broken or has a problem with disease,’ she says.

You can remove any plant matter that is fully brown and dead (using clean, sharp pruning shears like the Fiskars bypass pruners from Amazon). However, any foliage that still have green on them can still perform photosynthesis and may perk up after recovering.

Likewise, Lindsey warns it’s a fertilizing mistake to try and feed your heat-stressed plant:

‘Fertilizer is not going to repair any damage, and fertilizer tries to encourage new growth. With a heat-stressed plant, you don’t want to encourage growth. You want to encourage healing, so during a heatwave is not the best time to fertilize your plants,’ she explains.

Doing so can even burn plant roots, so it’s best to wait until temperatures are milder and your plant is showing signs of new growth and recovery.

What to Shop

Terracotta Watering Spikes

If you want to boost your yard’s resilience in extreme weather, it might be worth swapping some of your plants for the plants that thrive on neglect in a heatwave. Careful planting choices like this can even help reduce watering in the garden.

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