5 min readYou know it’s coming: A sweltering summer that stresses both you and your garden out. Some parts of the country may already be experiencing drought as well. Plants weakened by heat and lack of water—and that includes your lawn—struggle, making them more susceptible to diseases and insects. But there’s actually plenty you can do to protect your lawn and garden from summer’s heat.
Let’s start with your lawn. First, lawns are tougher than you might think and can survive if you focus on providing the right kind of care and maintenance.
“There’s no special treatment necessary, but you should follow proper horticultural practices to keep your turf healthy,” says Clint Waltz, Ph.D., turfgrass researcher and extension specialist at the University of Georgia. “That means maintaining proper fertility, mowing, and irrigation practices.”
If it’s hot and super dry, turf may go into dormancy. Though the plant will lose leaf tissue, it will conserve the crown of the plant, or the growing point, and rejuvenate when environmental conditions are favorable. “Most turf is hardy. It does a good job of surviving extremes and will do what it needs to do during a drought in order to survive,” says Waltz.
For ornamentals, such as perennials and shrubs, established landscape plants usually can make it through summer stresses on their own.
“Generally speaking, plants are considered established after their third year in the ground,” says horticulturist Stacey Hirvela, marketing manager for Proven Winners Color Choice Shrubs. “At this point, the plant has developed a robust root system to help sustain it through any challenges.”
However, how long it takes to get a plant established depends on a few factors. “Those in climates with a long growing season may find plants get established more quickly because they don’t have the disruption of a long winter when growth stops,” says Hirvela. “And of course, it depends on the care the plant has received. Plants that experienced significant stress during those first two or three years will be set back, whereas those that have had their needs met will be established more quickly.”
Read on to learn what you can do to ensure your lawn and plants survive summer’s coming heat.
Add a Layer of Mulch to Garden Beds
This is one of the simplest and most effective ways to protect ornamentals.
“Mulch prevents water from evaporating through exposed soil surfaces quickly, keeping it in the soil and around the roots where it can be used,” says Hirvela. “It also lowers soil temperatures by around 10 degrees Fahrenheit, compared to bare soil, keeping the roots at a cooler temperature that is more favorable to continued growth.”
Mulch is beneficial for most plants: The only exceptions are plants that prefer hot, dry conditions, such as cacti, succulents, Russian sage, and butterfly bush.
Apply Mulch Properly
If you’re going to use it, put it down the right way.
“Organic mulches—those that come from living things, like shredded bark, pine needles, compost, or partially decomposed leaves—are the best for maintaining optimal root growth conditions in the soil,” says Hirvela.
Apply about two to three inches of mulch around the plant, but “feather” out near the base of the plant so that it’s not touching stems or trunks, which invites disease and pest problems.
Don’t Stop Fertilizing
Lawns may look like they’re not doing much during the hottest days of summer. But stay the course with your regular fertilizer routine.
“Don’t increase nitrogen because it looks like your grass isn’t growing,” says Waltz. “But don’t get behind either, or the turf will become malnourished. It will rain again, and when environmental conditions are right, often after just one rainstorm, grass responds fairly quickly.”
Don’t Waste Money on Soil “Boosters”
Many companies advertise soil boosters or biostimulants for lawns with a “proprietary bacterial mix” that promise to improve rooting, heat and cold tolerance, and drought resistance for lawns. However, there’s little evidence they are beneficial in real life because much of the research has been done in a controlled environment, like in a greenhouse, not in the field.
“These products are expensive, don’t typically colonize in soil, and may pose negative effects,” says Waltz.
Water New Plants
As you’d guess, new plants are especially vulnerable to summer stress.
“In the intense sun and high heat of summer, plant foliage loses water more rapidly than it does during cooler, less bright periods, and that means that your plants can dehydrate quickly,” says Hirvela. “Plants in their first year should ideally never be allowed to dry out completely for that whole first season.” Test the soil by poking your finger into the area just outside the root ball of the plant to see how it feels. It should be damp, not sopping wet. If it’s dry, give your plant a drink.
Keep an Eye on Established Plants
Plants in their second year—and sometimes even in their third season—are still getting established and will benefit from sustained root growth.
“While the care is maybe not quite as crucial as the first year, in most cases, you shouldn’t just forget about these plants,” says Hirvela. “You may need to provide supplemental water, especially if the weather is very hot and dry.”
Mow Lawns at the Proper Height
Scalping your lawn doesn’t do it any favors. If you mow too low, your grass becomes stressed and sparse. Before a heat wave, raise the mowing deck a notch to give turf a little extra leeway before harsh conditions occur. Also, make sure to mow at the proper height for your species and region of the country.
“Remember, the higher the leaves, the deeper the roots grow,” says Waltz. Your university co-op extension service (find yours here) can offer guidance on ideal mowing ranges for turf species where you live.
Irrigate Correctly
Ensure your lawn is getting about one inch of water per week, or 1 1/3 to 1 ½ inches for sandy soils. Set out a straight-sided can under your sprinklers, let it run for 15 minutes, then multiply that by four to determine how much water you’re putting out in one hour, says Waltz. Then adjust your irrigation times accordingly—and make sure you’re not wasting water by spraying your driveway or the street.
Provide Shade for New Plantings, If Possible
If a hot spell is in the forecast, you can use shade cloth or move containers into a shaded area in the afternoon when the sun is hottest.
“This can help a lot, as it reduces how much water a plant gives off as it grows,” says Hirvela. “This is a good option for plants that may be able to withstand hot, sunny sites once they are established, but need a little help from you to get to that point.”
Time Your Plantings Right
It may seem like common sense, but wait to plant if a heat wave is forecast—it will be easier on you and the plants! Ditto if you have trips planned. If you don’t have a friend or neighbor who can cover for you while you’re gone—and even then, unless they are gardeners themselves, they may not understand the importance of keeping your plants watered—you’re probably better off waiting until your return, says Hirvela.
