How to Protect Your Plants During a Heatwave - Squire's Garden Centres

How to Protect Your Plants During a Heatwave

We all love a summer of hot weather. However, a heatwave can see temperatures soar towards up to 40°C in some parts of the country for days or even weeks. These temperatures pose serious health considerations for us humans, but it adversely affects our plants too, potentially leaving our beloved gardens looking very sorry for themselves, or worse, stressing out our flowers, shrubs, and trees so much so they never recover and die, even if established. So, it’s very important we take steps to look after our plants and gardens as well as ourselves.

Here are our top tips on what to do in the garden during a heatwave.

Things You Can Do

These are things you can do to help give your plants the best chance to endure the heatwave:

  • Water at the Right Time

The biggest issue in high temperatures and consistent dry weather is the soil drying out. Help negate this by watering early in the morning or late evening. Some plants may need a top up during the daytime too. If they do, aim to water right at the base of the plant to ensure they can soak up as much of it before it evaporates as possible. It is likely any plants in pots will require extra attention as they can dry out very quickly.

  • Apply a Mulch

Applying a good layer of mulch such as compost, well-rotted manure, bark, or another type around borders and pots will provide a layer of material to help keep moisture in the soil and the roots cooler. This is also particularly essential if there happens to be any roots visible at the surface as they can burn in the sunlight unless they are covered.

  • Move Container Plants into Shade

Container plants will dry out faster than plants in the ground. Take extra care of them by moving them to a shady part of the garden where they will be protected from the scorching sunlight.

  • Add Shade

Where possible, add shade for plants in the ground in beds and borders. This could be as simple as a large cloth, towel, or bedsheet, the darker and thicker the better. It doesn’t have to be pretty, just functional until the heatwave passes. Though there are specific products like shade sails you can purchase to create shade in the garden.

  • Make use of a Water Butt

A sustainable way to get water into your garden is by using a water butt. This way, you can easily recycle collected rainwater to use on your plants. And many plants prefer rainwater over tap water too, especially lime loving ericaceous plants because rain water is slightly acidic.

Things You Shouldn’t Do

Here are some things that you don’t want to do otherwise it can exacerbate an already stressful time for your garden:

  • Don’t Overwater or Flood

Overwatering is very easy to do and adds even more stress to an already stressful situation. It can make plants really suffer further. Even though it’s very hot, a balance should still be struck when it comes to watering. Keep a water diary or use something to measure the moisture in the soil. The lawn would also benefit more from an infrequent but thorough watering rather than regular soaks – grass is typically quite tough – so keep this in mind.

  • Don’t Cut the Grass

Cutting the grass can cause undue stress to the lawn and soil underneath. Taller grass casts a shadow that can help the lawn to retain moisture by not overexposing the soil underneath. If you mow the lawn, and worse still mow it with the lowest setting, then it will take the full brunt of the sun and likely cause some brown patches you’ll have to repair later.

  • Don’t Fertilise

Fertilising during a heatwave can make a problematic set of conditions worse for plants. This is because they will need even more water to be able to absorb and process the fertiliser. An influx of nutrients also makes the plants want to grow, which is putting even more stress on them that they just don’t need right now. Instead just keep to watering until the temperatures begin to fall again.

  • Don’t Keep the Greenhouse Shut

When it’s so hot outside it will only be hotter in a greenhouse. Get all the windows and doors open to allow airflow. It may even be too hot to keep anything inside so where possible plants, fruit and or veg should be moved to shadier areas. For any anything that cannot be moved, something like a shade sail or similar to place over the top and shade the entire greenhouse may be necessary.

  • Don’t Give Up on Heat Damaged Plants

If you find yourself in the unfortunate situation where some of your plants have suffered and wilted, or have gone a bit brown, don’t give up on them quite yet. Cut any heat damaged parts off and give it additional care and attention in the following days. Consider some of the additional care tips such as giving them more shade and a mulch and it is likely they should survive.

kid watering the garden

Help Your Plants During a Heatwave

Heatwaves may become more common in the coming years, and they are as stressful for our plants as they are for us. By following our tried and tested tips above you can ensure to give them a fighting chance to survive and thrive once the heat lowers again. Make sure you look after yourself too!   


You are now leaving Squire’s and visiting our careers website, to view and apply for our latest jobs.