We often think of winter as being a testing time for the plants in our garden. But summer, in many ways, is a lot worse. Here plants are exposed to baking heat and very little water. And the difference between daytime and nighttime temperatures can be extreme. Ultimately it can take its toll on your garden. Everything looked great back in May. Now that we’ve hit August, plants and flowers are starting to look a little dry and parched.
So the question for the keen gardener is, what precautions can be taken?
Think Creatively About Shade
All plants need some sunlight to stay alive. But too much sunlight without water can leave them wilted and dried. The sun evaporates away all the water in the plant’s leaf cells. And this causes them to shrink and to lose their turgidity. Fortunately, there are plenty of ways to shade plants, some of them quite inventive.
Your first option is to use natural shading. Perhaps you have taller plants or trees in your garden that create shadows for part of the day. Move any vulnerable pot plants under trees and away from direct, all-day sunlight.
If you can’t move plants to the shade, move the shade to the plants. One idea is to use bamboo stakes and cardboard to make a screen. If you live in low latitudes, the screen won’t work right in the middle of the day. But it will work for most of the morning and afternoon. And that will reduce the amount of time your plants are exposed to intense sunlight.
Another idea is to use lawn chairs. When you hear that the heatwave is on its way, move furniture into position to shade vulnerable plants. Of course, you don’t have to use just chairs. You can use pretty much any garden furniture you have available.
Garden centers are keenly aware of the threat that prolonged heat poses to plants. That’s why you’ll often find them selling shade cloths. These cloths can then be attached to wooden or bamboo stakes to create a tent for plants. Opt for light colors, like white, that will reflect the sun’s rays and prevent the plants underneath from cooking.
Some plants are more in need of shade than others, especially any plants you intend to eat. Lettuces, herbs, and cruciferous veggies are all particularly vulnerable to prolonged sunshine. This is because they are less hardy than wild breeds, and so require extra shade.
Get Smart About Watering
We all know that plants need water to survive. But when a heat wave looms, we need to get smart about how we do it. Pouring water on plants out of the watering can simply won’t suffice.
Remember, in the summer plants expend a lot of energy just protecting themselves against the heat. That means that in the midday sun, they don’t have the energy to draw up water from the roots. Watering your plants in the middle of the day won’t result in water going to where it is needed the most.
So what’s the solution? The first thing you can do is start watering your plants in the early morning, while things are still relatively cool. At this time of day, the plant will have enough energy to transport water to the leaves. By the time the midday sun comes along, the leaves will be well hydrated. And the plant will be able to defend itself against desiccation.
It’s also important to deliver water to precisely where it is needed. Just dumping a bucket of water over the roots is unlikely to help in the case of a heat wave. There’s a high chance of runoff when the soil is dry. And it takes time for the soil to absorb water effectively.
Drip irrigation is a good solution because it allows water to penetrate further into the ground. Remember, the roots of plants can extend up to two feet into the soil. And so it’s important to find a method of watering that actually gets water into the ground. Read ProIrrigation.com for details on how irrigation systems work.
You don’t want the soil to become too wet, however. Saturated soil can become a breeding ground for moss, fungi, and other undesirable plants. And this is especially true when the weather gets hot.
Choose Soil That Retains Moisture
When heat waves strike, the biggest threat to plants is the lack of water. Often, garden soil can become cracked and dry very quickly. And this cracking further exacerbates water loss from the ground.
But not all soils are created equal. Some soils are far better than others at retaining moistures. And it all has to do with the quantity of mulch that they contain. Abundantminigardens.com recommends a layer of mulch, about two inches thick, to help retain moisture. You can use straw, wood chippings and even cardboard in your layer of mulch.
However, you’ve got to be a little careful when it comes to mulch. Mulch can develop toxicity and slime molds, as well as artillery fungus. Putting it too close to some woody plants can cause damage. So keep your layer of mulch two or three inches from the base of trees. Also, make sure you keep it well away from the side of buildings and barns. Experts recommend a distance of between 6 and 12 inches to be safe.
Avoid Pruning Or Fertilising Plants
What is the purpose of pruning and fertilizing plants? It’s to help them grow. But growth is not something you want during a heatwave. As we discussed earlier, during heatwaves plants, put all their energy into staying alive. So the last thing they want to spend energy doing is growing. Both fertilizer and pruning cause plants to grow more rapidly. And this rapid growth during a hot spell can kill them.
It’s also important to avoid pruning, even when it appears plant leaves have wilted and died. Sure, leaves may have died. But they still protect the plant by providing the stalk with some limited shade. Wait until the hot weather passes before cutting back on any dead parts of the plant.