For more on water-efficient tree care, visit sactree.com/waterwise . To learn about branch drop -- common in summer -- read a previous post here .

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Speaking for the trees: Don't forget them in this heat

Invaluable shade for us and habitat for many creatures

My east-facing driveway is my early morning thermometer. When I step out there to pick up the newspaper or put something in my car, I can tell what kind of day we're going to have, especially in summer. (This morning: Pretty bad, but short of volcano heat.)

Just a few feet away, in the southeast corner of the yard, the air is at least 5 degrees cooler, and the grass is still refreshing on bare feet. That's thanks to the big redwood tree someone planted there several decades ago. Not a good choice for our climate, certainly, but that tree saves us money in air-conditioning costs for at least some of the day. It's also an entire habitat for the birds and squirrels, including the best lookout tower in the neighborhood for the local scrub jays.

I'd never get rid of that tree, so I baby it, and especially during drought and heat waves. (It's not the redwood in the photo above, by the way.)

Be good to your trees, and they'll continue to be good to you. Here are some tips from the Sacramento Tree Foundation and the UCCE master gardeners:

-- Know your trees! Native species of the Central Valley are well-adapted to the weather. Mature valley oaks, for instance, need just one or two deep waterings during the dry season. Redwoods like mine and other moisture-adapted trees (birches, magnolias, etc.) on the other hand, need regular deep waterings. And any tree that's planted near or in a lawn may have developed surface roots and have higher water needs. And young trees need more frequent irrigation than mature trees as they establish their roots.

-- Know your soil. Stick a screwdriver, a trowel or a soil probe into the soil around the tree about 6 to 12 inches. If the soil is dry and crumbly -- or rock-hard clay -- apply water slowly to soak down 12 to 24 inches. (See the tips at the end for ways to do this.) An estimated 85 percent of tree roots are in the top 18 inches of soil.

-- Know where to water. Irrigating at the base of a mature tree does nothing to help the roots, and might even cause rot. The roots extend out away from the tree much farther than you may think. Be sure to soak the root zone at least out to the drip line, defined as the soil beneath the edge of the leaves.

-- Know when to prune. During a heat wave, don't prune trees and other woody plants unless necessary (a cracked branch, for instance). Pruning stimulates shoot growth, which increases the need for water.

-- Know how to prevent rapid evaporation. Mulch, mulch, mulch! We say it a lot, because it works. Keep mulch a few inches away from the trunks of trees -- avoid "mulch volcanoes." Spread the mulch at least 3 inches deep across the root zone. This helps keep the soil cooler, will reduce weeds and will help retain soil moisture.

Methods of deep-watering trees:

-- Drip irrigation system that uses mini or micro sprinklers. (Make sure ANY sprinkler used doesn't splash water on the trunk or the base of the trunk.)

-- Soaker hose spiraled out to the tree's drip line. Reposition it as necessary.

-- A large, thin-plastic bucket with a couple of holes punched in the bottom. Position the bucket where you want to deep-water, fill the bucket and then let it soak in. Move the bucket and repeat. (This is labor intensive but does work, especially during drought water limitations. I found a 7-gallon clothes hamper that worked perfectly.)

-- Garden hose barely running. Also labor intensive (you have to move the hose a lot) but it will soak one area at a time quite well.

Prevent water runoff, of course, and don't water during windy conditions or during the middle of the day.

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Sacramento drought trees drip watering heat wave heat stress irrigation summer weather weather gardening oak trees heat water-wise gardening landscape trees

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Flowers in My Back Yard Series

April 28: Majestic Matilija poppy is worth a look

April 21: Celebrate roses, America's favorite flower

April 14: Small flowers with outsized impact

April 7: Calendulas do double duty

April 3: Make Easter lilies last for years to come

March 31: In praise of a pollinator magnet (small-leaf salvias)

March 24: Azaleas brighten shady spots

March 17: The perfect flower for beginners? Try zonal geraniums

March 10: Keep camellias happy for years to come

March 3: Fruit tree blossoms are a fleeting joy

Feb. 27: Are your roses looking rusty?

Feb. 24: Treasure spring daffodils now and for years to come

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Garden checklist for week of April 19

After this midweek storm, start getting serious about spring gardening. Flowers are blooming about three weeks ahead of schedule. That includes weeds!

* Get ready to swing into action in the vegetable garden – if you haven’t already. As nights warm up over 50 degrees, set out tomato, pepper and eggplant transplants.

* From seed, plant beans, beets, cantaloupes, carrots, corn, cucumbers, melons, radishes and squash; wait on pumpkins until May. Plant onion sets.

* In the flower garden, plant seeds for asters, cosmos, celosia, marigolds, salvia, sunflowers and zinnias. Transplant petunias, zinnias, geraniums and other summer bloomers.

* Plant perennials and dahlia tubers for summer bloom. Late April is about the last chance to plant summer bulbs, such as gladiolus and tuberous begonias.

* Transplant lettuce and cabbage seedlings.

* April is the last chance to plant citrus trees such as dwarf orange, lemon and kumquat. These trees also look good in landscaping and provide fresh fruit in winter.

* Smell orange blossoms? Give citrus trees a low dose of balanced fertilizer (such as 10-10-10) during bloom to help set fruit. Keep an eye out for ants. If leaves look yellow, your tree may need an iron boost -- apply some chelated iron fertilizer.

* Apply slow-release fertilizer to the lawn.

* Thoroughly clean debris from the bottom of outdoor ponds or fountains.

* Spring brings a flush of rapid growth, and that means your garden needs nutrition. Give shrubs and trees a slow-release fertilizer. Mulch with a 1-inch layer of compost, which helps the soil, but keep it a few inches away from trunks and stems.

* Azaleas and camellias looking a little yellow? If leaves are turning yellow between the veins, give them a boost with chelated iron.

* Trim dead flowers but not leaves from spring-flowering bulbs such as daffodils and tulips. Those leaves gather energy to create next year's flowers. Also, give the bulbs a fertilizer boost after bloom.

* Pinch chrysanthemums back to 12 inches for fall flowers. Cut old stems to the ground.

* Mulch around plants to conserve moisture and control weeds.

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