By Gerry Hernandez, UC Master Gardener
California is hot all summer. Many gardeners wonder how their plants, trees or shrubs can survive. With a little extra planning, your plants can survive the hot summer weather.
Don’t fertilize plants or trees during hot weather. Fertilizers increase the plant’s growth. An increase in growth means an increase in water and nutrient needs. Plants have a hard time pumping water to all parts of the plant during the heat.
Water trees deeply and frequently. You want to consider the roots below the ground and encourage a network of deep roots. How do you do this, especially if your tree is in the lawn. In a nutshell, circle your tree with a drip line or soaker hose. Turn the water on for about 2 hours. Check the depth of the water by using a measuring stick. The measuring stick will easily push through wet soil. When the measuring stick stops at 2 feet then you can turn off the water. Next week check the depth of the water using your measuring stick again. Once the level of wet soil reaches 1 foot, irrigate again. Keep up this cycle over the summer.
Mulch, mulch and more mulch. A good layer of mulch prevents soil from heating up and moisture leaving. Apply a 4-inch layer of medium bark mulch to the soil. This protects the plants’ fine roots. Mulch decomposes so you will have to add mulch every year.
Wait to introduce new plants or trees until the fall. Timing is everything. New plants have smaller root systems than mature plants and need time to develop. New plants have a high rate of failure during hot summers. In California, the best time to establish a new plant is in the fall. Winter rains can help keep new plants watered while their roots grow.
Precautions to Prevent Heat Illness Disorders for You
Gardeners and others should acclimatize themselves to the prevailing weather conditions.
Always drink plenty of fluids such as water and sports drinks. During warm weather, plan to have at least one quart of water available per person per hour of outdoor activity. Avoid caffeinated drinks.
Wear a summer hat with a brim and loose-fitting, light-colored, and lightweight clothing like cotton.
Schedule vigorous activities such as gardening, during the coolest portions of the day and take frequent breaks on hot days.
If someone is feeling symptoms of heat illness, they should take a rest period in a shaded area. Find access to shade – this may be any area where the affected person is protected from direct sunlight, such as under an umbrella, a portable structure, or inside a ventilated building or vehicle.
Heat Exhaustion – profuse sweating results in dehydration. Characterized by fatigue, dizziness, and nausea;
pale and moist skin; and possibly slightly elevated temperature.
Heat Exhaustion – have victim rest in shaded and cool place and drink fluids. Do not serve caffeinated fluids
such as soft drinks, iced tea, or coffee.
Heat Stroke – sweating stops and the body fails to regulate its temperature. Victims may die if they don’t
receive immediate medical treatment. Characterized by mental confusion, fainting, or seizures, hot dry skin
usually reddish in color; and high body temperature. Call 911 immediately, soak victim’s clothing with cool water, move victim to shaded and cool area, fan victim to increase cooling of their body.
Source: University of California Agriculture and Natural Resources. Visit ipm.ucanr.edu or cecolusa.ucanr.edu.