15 Tips For Keeping Plants Alive in Hot & Dry Conditions

The summer season seems to be getting hotter and hotter all over the globe. As gardeners, many of us are seeing plants in our gardens suffer in times of extreme heat. In many places, water restrictions are also put in place to conserve water resources. This can make keeping plants watered and healthy, or even alive, difficult.

When you approach 100 degree heat or higher in certain environments, you’ll find peonies dying in a day, and watch your tomato plants get sun blisters. Lettuce bolts quickly, and even zucchini or other squash plants can start to suffer.

While there is not much we can do to change the weather, we can change our gardening habits to help our plants cope with extreme heat and drought. Here are 15 tips you can use that will help keep your garden looking its best through heat waves.

Use Plenty of Mulch

Mulching your garden beds is a great way to retain water and lower the soil temperature. This is a great way to combat drought and heat stress on plants.

There are various things you can use as mulch, straw, bark chips, compost, shredded leaves, even grass clippings.

Mulch around the base of plants, leave a couple of inches around the actual stems of the plants so they don’t get crown and stem rot.

Start Watering Early

The time of day you decide to water is important. Early morning is the best time. This will ensure the plants get enough water to endure the hot day ahead. If this isn’t an option, late in the evening is the next best time.

But it isn’t the best as it leaves the leaves wet for the whole night, make the plants more susceptible to fungus and rot. Plants watered in the morning will quickly dry in the sun.

Avoid watering in the heat of the day. If you are watering in the heat of the day, a lot of the water will just evaporate and not reach the plant’s roots. If you decide to start planting new perennials in August, make sure to step up your watering schedule even more to help avoid transplant shock.

Water Deeply When You Can

A quick spray of your plants is not enough in extreme heat. Make sure to water deeply. Watering less often, but deeper, is far more effective than spraying the surface more often.

I recommend snaking a drip hose through the beds and letting it slowly seep into the soil. For large trees I will sometimes just let the hose slowly trickle out at the tree’s drip line (the width of the canopy). Large trees require a lot of water, don’t let them get dry and heat stressed, it’s hard for them to recover.

Watering deep will encourage plants to produce deeper roots and will be able to reach more water than shallow rooted plants. This will help plants cope in periods of drought.

Take Extra Care of New Plants

New plants added to the garden will need more attention than already established plants. 

Do not plant new plants into the garden in the midst of a heatwave. If you have a plant that needs planted, hold off. Keep it in its nursery pot in the shade and keep it watered until things cool down.

When you are planting a new plant into the garden, dig the hole extra wide and deep. Double the size of the container at least. Add a mix of new loamy soil and the existing soil when planting it.  This will create soft soil for the plant to reach its new roots out into and it won’t have to use so much energy pushing through hard soil.

Water them in well. I will create a little groove of soil around the plant to hold water in. Planting like this before a heatwave will help give your new transplant a head start at establishing roots.

Keep a close eye on newly planted plants. Water them more often and deeply so they can establish strong roots. Using watering bags around newly planted trees will help keep them watered until they establish deep roots.

I also might be the crazy plant lady, but I will cover a newly planted plant with a shade cloth or an umbrella to keep it protected until it can establish itself.

Water the Ground

When it is time to water aim for the soil. This is why I like to use a drip hose. You want to get the water to where it needs to go, straight into the soil. Spraying the leaves, especially in the heat of the day will just evaporate. It is actually a myth that the water droplets on a plant will burn the foliage.

Sprinklers and irrigation should only be run in the early morning hours. Watering overhead at night will leave the plants wet for a long time (until the sun the next day dries them), leaving them more susceptible to fungus and disease.

Reuse Your Water

I reuse a lot of my water. If I’m boiling carrots or potatoes I save that water, let it cool, and use it in my garden. It provides nutrients and is far better used in the garden than down the drain.

If you really want to get thrifty and water-wise, have a bucket that catches unused water. When you turn on the shower, collect the water that runs before you get in and use that to water houseplants and/or the garden.

I will water plants with bath water, and I always pour the ends of water glasses into plants. While it might not seem like much, it all adds up. Just watch for any soaps, detergents, or salt that may be in the water.

Hoses Can Be Like Liquid Lava

One more watering tip. When you first turn on the hose grab a bucket, or aim away from all plants and grass. A hose that is lying in the sun will have boiling hot water come out of it at first. It will burn both people and plants. So let it run and cool off before using the hose.

If you do accidentally water a plant with the molten hose water, flush it out with as much cold water as you can.

Create Some Shade

Creating shade is another great way to protect plants. This can be done in a variety of ways.

Shade cloth can be purchased from the garden center and can be placed over crops and plants. Or it can be used to block out the sun in green houses. Don’t want to go out and buy shade cloth? no problem, old sheets work great too.

Shade sails, tarps, umbrellas, or a portable gazebo (like the ones you set up at the beach) can provide shade to heat stressed garden beds. These temporary structures will give your plants some relief from the sweltering hot afternoon sun. You can move them around as necessary.

Skip the Fertilizer

I think we all have the inclination to try and save our plants as they look sad and wilted in extreme heat. But resist the urge to apply fertilizer at this time.

Fertilizers will cause fast growth in plants and they will require more water, which is hard to provide in the midst of a heatwave. Just let your plants be and wait out the hot dry spell.

Leave it Alone

Unfortunately, there isn’t much you can do to help a heat-stressed garden in most situations. The best thing you can do at the height of a hot day is nothing. Let the plants be.

Don’t prune, split, transplant or do any major garden task in the heat. Plants are not able to recover quickly. You can weed in the heat of the day, but weeds are easier to pull when the soil is moist.

If you do notice a plant needs a drink, do not wait until the morning to do it. Go and water it before it gets to the crispy point of no return.

Plant Heat Tolerant Plants

I know this isn’t much help when you’re already in the throes of a heatwave. But I think it is time we all start moving in the direction of more water-wise, heat-tolerant plants.

Native plants are always a good choice. Look up plants that are native to your area. They are uniquely adapted to the conditions and require far less water and maintenance than the exotic aliens we like to introduce.

When in doubt, choose silver plants. Silvery foliage plants are usually water-wise choices. This includes silver mound, lamb’s ear, lavender, and dusty miller.

Succulents and cacti are also a great choice for hot dry conditions.

Look for varieties of vegetables that are specifically bred to be heat tolerant. ‘Arkansas Traveler’, and ‘Heat Master’ are some heat-tolerant tomato varieties. ‘Muir’ is a heat tolerant variety of lettuce.

Make Use of Containers

Containers are especially sensitive to heat waves. They have less soil and dry out and heat up faster. In extremely hot weather I give my container plants some extra attention.

Move your containers into a shady area if possible. If you are able to pick up and move the container, move it somewhere shady.

Choose lighter colored containers. I know a big dark black pot is striking, but it also absorbs the heat. Opt for light colored pots if heat is a concern.

Bottom watering containers is a great way to ensure they are getting enough water. One hot summer I bought a small kids pool and I called it the plant infirmary. Any droopy container plant went into the tub.

When the water is able to fully absorb into the soil it is perfectly watered. Sometimes over watering pots is not enough, especially when they have dried out. If you water your container and it just floods out the bottom it is a sign it is very dry and you will either need to really soak it, or bottom water.

For hanging baskets, I also like the bottom watering trick. But if you cannot do that make sure you water long enough for water to start pouring out the bottom, and maybe even longer still. Then you might have to do that twice a day depending how much sun they’re in. Hanging baskets have hardly any soil in them and can dry out quickly.

Use Moisture Retaining Soil

If you have that soil that gets a cracked crust on top, it is not moisture retaining. Even when you water that soil it will run off without absorbing. Amend your garden soil so it is nice and loamy. Add peat, or coconut coir to beds so water can absorb and be slowly released into the plants. Do this in the early spring or fall.

For containers, you can get water absorbing beads or soils that contain them. I would not use these for vegetables but for flower pots they will hold moisture. I’ve even seen people cut up diapers and mix the absorbent beads into the soil to retain moisture (only do this is containers with flowers, never into garden beds or in pots with veg).

Remember Your Houseplants

We are all suffering in the heat, and I think we forget about our houseplants in the height of garden season (I know I do). But it is important to think of our houseplants in extreme weather.

Keep them watered. Houseplants require more water in their active growing season. Depending on the plant will depend on exactly how much. But most of our tropical houseplants like to be kept evenly moist throughout the summer.

Draw the drapes if the afternoon sun gets particularly intense. This will prevent the leaves from bleaching. Then open them in the evening and morning and let them get the less intense light.

Add humidity, heat tolerant plants in their natural habitats usually will have humidity along with the heat. So run a humidifier, or mist the leaves often so they don’t get dry and crispy.

Take Care of Yourself

We’ve taken care of the plants, what about the gardener? As a professional gardener I don’t get to stop working because of a heat wave. I’ve learned to cope with the hot conditions. Here are some things I do.

I start work early and end in the afternoon when things get really hot when I can.

I wear long pants, a shirt and then a light button up shirt. Wearing less clothes makes you hotter. The more you cover from the sun the cooler you’ll be. When it gets really hot I will take off the light button up and soak it with the hose and put it back on. I also wear a very wide brim hat and sunglasses. Sometimes I wear a bandana around my neck that I will also soak with the hose.

Drink lots of water, and take breaks when you need them.