Watering the Garden in Hot Weather: Tips for Success

by Matt Gibson

If you live in a hot weather region, or if you are gardening in the middle of a heatwave, knowing how and when to water your plants for optimal efficiency is essential. If you know the ins and outs of how to water in hot weather conditions, you can keep your plants happy even in the most insufferable conditions.

Much ado is made about knowing when to water your plants, and while timing is very important, especially in hot weather climates, knowing exactly how to water your plants is just as key. As far as timing is concerned, the best times to water your garden and lawn is early in the morning, and once the sun has gone down in the evening.

A commonly repeated myth states that you should avoid watering in the heat of the day because the water droplets left on the leaves of your plants will heat up in the sunlight and cause scorching or burning of the leaf surface. This is untrue. However, watering during the heat of the day should still be avoided, but for different reasons. The reason midday watering is frowned upon is simply because it is a waste of water. During the afternoon hours, the sun is high in the sky, and its rays bake the soil throughout the middle of the day. When you water during the afternoon, you lose a lot of that water to evaporation.

You should still do what you can to avoid getting water directly on the surface of the leaves of your plants when watering. This is not to avoid leaf scorching from the elevated temperatures, but to avoid issues with rot and fungal infections. Installing a watering system that gets water directly to the roots of your plants is ideal, but installation takes a lot of work. If you can’t swing it, you can still minimize leaf moisture by watering your plants close to the ground level instead of raining down on them from above. When watering, soak the ground around your plants, aiming for the roots.

Another important tip to remember when watering your garden in the heat is to water deeply. If you are watering with your garden hose set to shower, give each plant a good 20 second drink before moving on. To see if you’re watering deeply enough, dig up an unplanted area of your garden and check to see if the soil is moist at least eight inches below the surface level. If so, you have watered that area deeply. Remember that plants which are housed in planters and pots will need to be watered more frequently, as the soil inside of containers tends to dry out much quicker than the soil in your garden beds.

Your garden’s moisture level is something you need to focus on if you want to garden successfully, so keeping an eye on it is key. Overwatering can lead to all kinds of problems in the garden, including root rot, and fungal infections. Soggy soils can also create an environment that attracts pests, which can be a nightmare for vegetable gardeners. Allowing the soil to dry out completely can be just as disastrous as overwatering, leading to stunted growth, wilted foliage, and can cause your plants to fail to flower or produce fruit.

Gardens and lawns need just the right amount of moisture in order to grow correctly. If you allow your soil to dry out completely between waterings, your plants will wilt and wither. However, if you work with your rain gauge and keep the soil consistently moist throughout the summer months, your garden will thrive. Don’t be afraid to put a finger into the soil every now and then to check the moisture level. It’s actually the most fool-proof way of figuring out whether your plants need water.

Another easy trick to help you keep your garden watered properly in the summer is to find a plant that serves as a warning sign that your garden needs water. No matter what you plant, there will be a few plants that suffer from the moisture-zapping heat of the summer more than others. As the summer heat wave begins, keep an eye on which plants seem to wilt or sag first when they could use a drink. If you find a plant or a group of plants that show signs of summer fatigue before others, you can use that plant or plant group as a visual reminder that you need to break out the watering can or gardening hose and make it rain. Many plants send out obvious distress signals when they are thirsty, but are quick to bounce back in the evening after a deep watering.

Keep some sort of rain gauge on your property so that you can keep an eye on how much water your garden and lawn are receiving naturally during the summer, so that you know how much you need to supplement each week. During hot summers, especially in warmer climates, you may need to water your garden more than you think.

A daily watering session may be enough for well established plants or more mature specimens. But younger plants or more delicate ones may need more attention than that. Some of the plants in your garden may need water twice each day in order to grow healthy and strong. So while most of your plants will do well if you water them either in the morning or at night, the younger and more delicate plants may need watering both in the morning and in the evening. When the sun is really hot, like in the summertime, you may need to water before 9 a.m. to really avoid the summer heat.

The most sensitive of your plants may benefit from being protected from the sun somewhat. You can pick up and move plants already growing in containers, or dig up your plants to give them pots of their own. Alternatively, you can move tall plants so their shadow is cast on the ones you want to protect. You can also turn to products like shade cloths or row covers to cast some shade on your delicate plants.

One way to reduce the amount of water your plants need is to add a layer of mulch to the surface of the soil around them. Make sure to leave a border of a few inches of empty space between your plants and the mulching material to help prevent disease in your plants. You should make sure that the mulching material is never touching the stems or leaves of your plants by keeping the border empty.

Two to three inches of your selected mulch material spread around your plants does a lot to reduce water loss and regulate the temperature of the soil. You’ll find that plants in your garden need 25 percent to 50 percent less moisture after adding mulch. That’s because the mulch keeps the temperature of the soil down, which reduces the amount of water plants need, and mulching your garden also reduces the amount of moisture lost to evaporation.

Lots of different mulching materials are available, and the best one depends on your garden and your goals. For reducing water loss in hot weather, some of the best mulches to consider are coconut coir, grass clippings, peat moss, shredded bark, or shredded leaves.

If your area is really having a heat wave, you should postpone any fertilization you may have planned for a while. When the weather gets too hot, your plants go into a kind of survival mode that is similar to dormancy. They won’t be able to absorb and consume the nutrients in fertilizer like they normally would if the weather is too hot.

To sum things up, water deeply and water at morning and evening when the sun is at its gentlest. Water plants at the base and don’t splash their foliage. Once per day is enough for most plants, but delicate or young plants can be watered twice daily. You can use shade (from tall plants, row covers, or shade cloth) to protect really delicate plants. Don’t use fertilizer when the weather is really hot. Your best defense against moisture loss in the heat is a layer of two to three inches of mulch. Keeping these tips in mind and putting them to use in your garden will keep your plants well hydrated even when the weather is hot.