The searing summer heat has returned to our area with a vengeance. Several consecutive days of 100-plus readings can sap the strength of area gardeners while wilting or killing underwatered plants. Wilting, though, is a natural defensive mechanism used by many plants during hot afternoons to conserve water. It's when you see a wilting tomato vine, coleus or fuchsia in the morning that you know your plants probably need a good, long drink of water.

Mornings are the best time for both humans and plants during heat waves to take care of weather-related outdoor garden problems. As you enjoy the briefly cool early hours outside, keep these hot weather garden tips in mind:

Don't let the dry surface of the topsoil fool you. Check the soil moisture down at the root zone, about eight to 10 inches deep. If it is only the top few inches that are dry, and your established plants look healthy, fight the urge to waterlog those roots.

Even during heat waves, lawns and gardens do not need to be watered every day; two or three times a week is plenty.

Newly planted annuals and emerging seedlings, though, have shallower roots. New seedbeds and young plants may need a daily drink.

Containerized plants in the sun probably need watering every day during heat waves. Raise containers off the ground with a plant stand or a couple of pieces of wood or bricks. This will keep the pot cooler by improving air circulation.

The downside of daily watering of potted plants: fertilizer is leached out the soil more quickly. Instead of a once a month regimen, fertilize plants in pots every two weeks; just cut the fertilizer dosage in half.

During extended heat waves or if you are going on vacation, consider grouping containerized and hanging plants on a cooler side of the house, such as the north or east side.

Add mulch. A four inch-deep layer of bark mulch, applied beneath the canopy of trees and shrubs, will help conserve water, control weed germination and keep the soil cooler.

Just because it's hot, don't love your drought-tolerant California native plants to death with too much water. Ceanothus and native oaks, especially the blue oak, prefer it on the dry side in the summer. A once-a-month watering is plenty for them this time of year.

If your travels include a trip to the garden center, make it the last stop of the day. A plant left in a hot car for as little as 15 minutes may stress it beyond recovery.


Looking for plants with "hot" names? How about: sunflower, sundrops, sunrose, red hot poker, blazing star, flame bush, flame tree ....