How To Protect Your Garden From Extreme Heat

It’s tough to beat the heat. As temperatures rise and summers get hotter, protecting your plants from heat stress becomes increasingly crucial to a lush, healthy garden.

While no one has ever won a battle against the sun, there are steps you can take to shield your plants from the dangers of extreme heat. And, if the sun’s rays have already ravaged your yard, actions are available to revive your greenery.

So, don’t let the summertime sweltering get you down. Instead, check out some of our tips for protecting your garden from extreme heat.

What Are the Signs of Heat Stress in Plants?

We’re lucky to have homes we can return to when temperatures start to climb. Our gardens and lawns have no such luxury.

For many plants, a sustained thermometer reading of 90 degrees Fahrenheit is enough to display signs of heat stress. Once temperatures consistently hit triple digits, it can be hard to find examples from your garden that aren’t experiencing some sort of strain.

So, if you’re concerned about your garden this summer, keep an eye out for these symptoms of heat stress in plants:

• Bleached spots
• Blistered fruit
• Brown dry spots between leaf veins
• Dried, brittle leaf edges
• Dried-out fruit
• Premature blossoms or fruit drops
• Rolling or cupping leaves
• Spots of discoloration
• Unexpected early flowering
• Wilting

Each of these indicates a lack of water, extreme air or soil temperatures, or extended exposure to the sun’s rays. When these conditions persist, the plant takes steps to secure survival, such as dropping nutrient-sapping fruit before it is ready or attempting to reduce its unshaded surface area.

Sometimes the signs may be time-specific. Some plants may wilt during the hottest parts of the day but resemble something more akin to their typical self during cool mornings and nights. 

So, if you’re concerned about how the temperatures are treating your lawn and garden, you should conduct your examination when the sun is up and scorching. Checking at night may provide a false sense of confidence in how your plants are holding up.

Will Plants Recover from Heat Stress?

The easy answer here is “It depends.” Prolonged exposure without treatment or protection will result in the death of your greenery.

On the other end of things, and as mentioned above, some plants may recover once the heat spell ends. Fruit-bearing plants, for example, may drop their gifts earlier than expected during an especially hot summer but return to their typical production cycle when things cool down.

However, for those plants to hop back on their fruit-bearing circuit, they have to survive the sweltering summer. A dead flower can’t return to anything.

So, critical to the recovery of any plant is taking steps to protect and support it when temperatures are at their sweatiest. To do so, you have to act quickly upon spotting any signs of heat stress.

How Do You Save Plants from Heat Stress?

If you’ve spotted the signs of heat stress in your lawn or garden, it’s time to take prompt action. The goal here is to reduce stress of all types, discourage growth, and shield plants as much as possible from harsh sunlight and high temperatures.

Before discussing what you should do to save your plants and lawn, let’s talk about what you shouldn’t do.

First, if you’re seeing signs that your plants are not adapting well to the hotter weather, now is not the time to go on a seed-planting binge. There’s a good chance the hotter-than-typical soil will kill the seedlings before they sprout, and if they do sprout, you’re adding another competitor for a dwindling supply of water and nutrients.

Along these same lines, hold off on fertilizing until things cool down. Fertilizer encourages growth, and as plants grow, they need more resources. If the resources aren’t there, they’ll experience unnecessary stress.

Additionally, you may be tempted to prune trees, shrubs, and plants, especially if you spot areas experiencing sunscalding. However, pruning already damaged leaves or branches will only expose undamaged parts of the plant to the sun.

Sunburnt leaves may not be attractive, but an otherwise healthy tree or shrub may recover. If you continue to stress the plant by continually revealing new portions of its canopy to the sun, you’ll likely damage the plant beyond its ability to recover.

This same list of don’ts also applies to lawns. If you notice patchy, uneven spots in your lawn, reserve applying nutrients and mowing until the heat dissipates. 

To save your plants from heat stress, there are some proactive things you should do. Adding mulch to your garden can help keep the soil moist and at a consistent temperature.

If your garden is experiencing sunscalding, provide shade. A picnic umbrella deployed during the late morning and removed after temperatures descend (but before the sun fully sets) allows your greenery to get necessary but not overwhelming sunlight.

If you lack a picnic umbrella, shade cloth can also serve as a shield against that giant heat orb in the sky. And if your plants are in containers, moving them into the shade during the hottest parts of the day will prove beneficial.

While you may not spend as much time in your garden during bouts of extreme heat, some tasks are still required. Weeding, for instance, remains mandatory to help reduce the competition for nutrients and water.

Should I Water My Garden Every Day in Hot Weather?

Speaking of water, you may need to adjust your watering habits during especially hot summers. You should also check out your local code, as some municipalities limit how often and when you can water your garden.

When watering during extreme heat, there are a few things to keep in mind here.

Many plants have root systems that extend far below the surface of the soil. That means deep, daily (or every other day) watering is better than shallow watering.

It’s generally recommended that you water your plants in the morning to avoid rapid evaporation and wasted water. The only exception to this is if you notice any wilting plants; in that case, water the wilted immediately then resume your morning application going forward.

When watering, try to do it manually as much as possible. Overhead sprinkler systems may spray water where it’s not needed and typically only help with surface-level moisture issues. 

If you’re not sure of your soil’s moisture level, test it with a screwdriver. Properly moist soil will allow easy penetration all the way to the tool’s hilt.

The goal with all these watering tips is to ensure you’re using the life-sustaining liquid efficiently and effectively. Daily watering is good, but deep watering is more beneficial. 

What Plants Tolerate Heat Best?

Another way to protect your garden from the stress of extreme heat is to plant greenery that’s sun, heat, and drought-tolerant. These plants are less fussy and more likely to survive, if not thrive, when others wilt.

We’ve written about this subject before, but here’s a quick rundown of some of our favorite drought-tolerant plants:

• Canna lilies
• Coralbells
• Fountain grass
• Limelight hydrangeas
• Okra
• Rudbeckia
• Summer squash

A brief note about hydrangeas: while we’ve listed the limelight variety above, other varieties (such as bigleaf hydrangeas) are less tolerant of heat, sun, and drought.

Protect Your Garden From Extreme Heat This Summer

In a world that’s getting hotter, it’s becoming harder to protect your garden and lawn from heat stress. However, with our tips and tricks, you can help keep your plants safe and healthy all summer long.