Whether you’re in a hot and dry climate, or you’re wondering how to grow seed or keep your lawn green during the warmest months of the year, it’s a challenge that can usually be overcome. It’s the toughest part of the year to grow grass, but some grasses love the heat and can be grown from seed as long as they receive enough water.
Mature grass often goes dormant from the heat, but it can be kept green if you give it the right attention. Some grasses have more drought tolerance than others, so your results may depend on the type of grass that you want to plant or is already in your yard.
Can You Grow Grass In 90 Degree Weather?
Sports fields and high-use yards often need to be overseeded or spot-seeded in summer, and it’s possible to miss the early summer planting period from time to time. No matter the reason, grass seed can be sown and grown in the middle of summer with the right care, even if it’s not the ideal time to plant.
Grass seed needs to stay moist to germinate and sprout properly, so if you’re planting in July or August, you’re going to have to be more on top of watering than usual. Seeds and seedlings like lots of light, and the grass might struggle more during these months from the intensity of the sun.
For this reason, it’s easier to overseed and spot-seed during the summer since there is grass present to provide some shade and cooler ground temperatures. Planting too late in summer, however, risks running into early frosts, which can damage and kill grass that hasn’t matured enough to have prepared for dormancy.
One of the best ways to ensure your grass will grow even in the warmest temperatures is to plant a warm-season grass. These include Bermuda, Zoysia, St. Augustine, and Centipede grass. Buffalo grass does especially well in hot and dry areas, being the most drought tolerant of all the warm-season grasses.
How Do You Grow Grass In Dry Weather?
The heat can create dry air, the enemy of germinating seed. When grass grows in spring, early summer, and fall, it benefits from the wet or humid seasons. In areas where the summers are bright and dry, choosing to plant coated seeds, or using a hydromulch to apply your seeds, will help keep in moisture and increase the germination rate.
Seeds should be watered 2-3 times a day, particularly if it’s not raining, even when using coated seeds or hydromulch, neither of which substitutes for regular watering. When a seed dries out, the germination process stops and fails, and it can’t be restarted. Keeping the seed moist is essential for them to sprout.
Mature grass will normally go dormant when the air gets too dry, and the lawn dehydrates. This is normal, and different types of grass have different levels of drought tolerance. If Bermuda or Zoysia goes dormant, it will bounce back quickly when given water, but St. Augustine, on the other hand, is less drought tolerant: if it dehydrates for too long, it will die.
This is because Bermuda and Zoysia have complex root systems that can store more water than St. Augustine, which has many surface-level roots that can dehydrate quickly. To keep your grass green in drought, make sure it gets the right amount of water for its species.
Should I Change My Mowing Schedule In Hot Weather?
Mature lawns will slow down their growth in the warmest and driest parts of the year when they have to conserve energy to tolerate the stressful conditions, so its recommended to set your lawn mower cutting height a little higher and to mow a little less frequently, giving a few more days in between cuttings. If grass is cut too low or too frequently in summer, it might become stressed from too much moisture loss.
This is particularly true for cool-season grasses in northern climates that can make it through summer with care. Although the proper mowing height will vary by grass type, all kinds of grass keep themselves cool in the summer in a few ways:
- Shading itself – Grass keeps itself cool by providing its own shade, with each blade providing shade for the ones around it
- Thatch – Thatch protects topsoil and keeps it from losing as much moisture as it would if the ground was exposed to air and sun. It also covers the base of the grass blades while also preventing topsoil loss, or erosion, from dryness and wind.
- Photosynthesis – Blades of grass actually absorb the heat that reaches it, rather than reflecting it and heating up the area around it. The grass absorbs sunlight with its chlorophyll to create the energy it stores and uses to grow, heal as necessary, and endure stressful conditions.
- Transpiration – Plants let out moisture to “sweat”: internal moisture holds heat, so the plant releases some to regulate temperature, dehydrating itself. This is in addition to normal moisture release from transpiration (one of the ways plants breathe) and moisture loss to evaporation from heat.
What’s The Best Way To Keep Grass Hydrated During Summer?
One of the easiest ways to make sure your lawn stays hydrated during summer days is to do your weekly waterings at dawn. By watering in the very early morning, the moisture has time to seep into the ground and be absorbed by the grass before the sun warms up the yard and evaporates excess moisture.
When you water in the middle of the day, the ground and air might be warm enough to evaporate much of the water before it can soak in and be absorbed. If you water at night, not enough of the water will be evaporated or absorbed, and it can create conditions for root rot or mildew to take hold.
Dividing your lawn into different areas to spread out the watering time, watering each once a week, can help spread out the task. Timed sprinklers are another way to make sure your grass is getting enough water during the week, and spot-watering patches or dormant grass as necessary can help you keep your yard evenly green and out of dormancy throughout the season.
Can I Fertilize When It’s Hot And Dry?
You shouldn’t fertilize mature grass when it’s hot and dry. If you’re planting seed on bare soil and the ground needs fertilizer, then you can apply the right NPK ratio for what’s needed. When overseeding a lawn, however, adding nitrogen or phosphorus might stress out the existing lawn. If the grass is growing and staying alive but seems to be less vibrant than you’d like, checking the iron levels and adding a liquid iron may help the grass green back up.