Hot weather gardening tips (2024)

FAQs

How often should I water my garden in 100 degree heat? ›

During extremely hot weather (daytime temperatures above 90F and nighttime temperatures above 70F), try to water daily or every other day. In a 10x10-foot garden, this would mean giving your plants 8 to 9 gallons of water each day.

So, how hot IS too hot for plants? The general answer is around 90 degrees F, with some exceptions to the rule. This means that when temps rise above 90 and remain there for a lengthy spell: Leaves wilt.

If you are gardening in really, really hot climates like Southern Florida, Texas or Arizona, you might want to focus on vegetables that do well in extremely hot weather. Vegetables like corn, okra, eggplant, hot peppers, tomatillos, and even though they aren't vegetables, melons like watermelons and cantaloupes.

Provide shade or use shade cloth during peak sun hours. Consider using drought-tolerant or heat-resistant plant varieties. Improve soil quality by adding organic matter to enhance water retention and nutrient availability. Use water-conserving techniques like drip irrigation to reduce water wastage.

Misting doesn't replace watering. "Most plants (with the exception of air plants) absorb moisture through their roots, rather than their leaves, so getting water on their leaves doesn't really help much," says Hanco*ck.

Plants in containers dry out faster than plants that are growing in the ground, and during a heatwave they may need watering more than once each day. When you know an extreme hot spell is coming, it can help to move smaller containers into shaded areas just for the duration of the hot weather.

General tips. Avoid applying fertilizers when plants are dormant or under heat and drought stress. Fertilizers should be incorporated into the soil to prevent losses. If you cannot physically incorporate a fertilizer at this point in the season, it may be best to stick with a water-soluble fertilizer.

It can take anywhere from a couple of days to a couple of months for stressed plants to recover. Recovery time depends on the amount of damage that the heat caused to the plant. If a stressed plant is completely neglected during a heatwave, it can take several months or even be impossible to revive it.

In extremely hot weather, consider giving your grass a solid 2 inches of water weekly. Grasses in drought-prone areas may even need watering twice a day, but this varies from situation to situation.

Wilted, drooping leaves, resulting from a combination of excess water loss and high internal temperatures, are often the first signs of heat stress. Sunburn is another type of heat damage caused by excessive exposure to direct sunlight. Sunburned leaves and stems become discolored and appear scorched.

Do plants stop growing in extreme heat? ›

Above 104°F, many plants will survive but will show different signs of heat stress depending on plant type, maturity of the plant and factors that often come with high temperatures, such as drought or wind. Extreme air and soil temperatures slow down chemical activity and growth in plants.

Shade cloths are effective tools to protect your plants from too-bright sun and keep the surrounding soil cooler, helping it to better retain moisture. They allow enough airflow and sunlight through to keep your plants happy but without scalding them.

Treating Heat Stress Recovery

Place temporary shading, such as shade cloth, over plants to keep them cool and block out the sun's rays. Deep water plants first thing in the morning, if possible. Do not fertilize during times of heat stress. New growth is especially susceptible to the effects of heat.

Mulch with straw

For tomatoes in the ground or in raised beds, put a 3-5 inch-thick layer of straw mulch around tomato plants. This helps keep the top layer of soil cooler and prevents excessive evaporation of water. See our more detailed post about how to mulch with straw.

Plants have to depend upon the proper utilization of water and other elements. The short of it is that your plants need more water in extreme heat, but it's not just the amount of water that matters. Plants also need water to be applied in the most beneficial way.