Planning your Garden for Increasing Temperatures

The summer of 2021 was a record-setter. In June, it was already 113 degrees in my backyard. In the home garden, at least in the foothills of the Sierra Nevada, it was a bad year for tomatoes. The heat was so intense that plants “sat still” and didn’t grow. Even shade cloth did not create better-growing conditions.

What can you do to protect your landscape and garden from future heat waves and the concurrent need to save water? It’s not necessarily about ripping out your lawn and planting California natives, although lawns can use three to four times the amount of water as drought-tolerant species. Consider these critical concerns listed by the UC California Garden Web: 1) water availability, 2) how your site affects water quality elsewhere, 3) energy use, 4) materials to the landfill, 5) fire-safe landscaping, 6) soil degradation, 7) the spread of invasive plants, and 8) wildlife habitat. Your goal, according to the UC IPM website (http://ipm.ucanr.edu/QT/landscapedesigncard.html is to, “Create an attractive landscape that reduces the need for pesticides and fertilizers, avoids runoff, and conserves water.”

Let’s consider the first critical concern. “Landscape watering can often be reduced by 20%-40% because over-irrigation is very common. Gradually reduce the amount of water applied over a few weeks – giving lawns, trees, and plants time to adjust” according to the University of California’s drought garden tips here. An easy way to decrease irrigation is to schedule one additional day between irrigation sessions.

Don’t rip out your lawn and plant California natives or Mediterranean-adapted plants during the spring or summer. All plants, even natives, need consistent water during their first year of becoming established. Drought-tolerant plants are best planted during the late fall or winter when they can take advantage of the extra moisture from winter precipitation.

Landscape and orchard trees provide a suite of benefits, including: stormwater interception; shade, cooling, and reduced energy use; fruit for humans and wildlife; and increased physical and mental health. Your landscape trees should be the focus of any drought-survival irrigation strategy, with a deep watering once to twice per month during the hottest part of the summer. Research from Igor Laćan, UCCE San Francisco/San Mateo Counties Urban Forestry Advisor suggests choosing new trees that are adapted to two climate zones warmer than your current location. Pretend that you live in Bakersfield and choose a tree accordingly. Selectree (https://selectree.calpoly.edu/) can help.

Conserve the life of trees and shrubs by reducing pruning. This slows down rampant future growth, increases shading and requires no fertilizer. Any pruned materials can be broken up and left lying on the surface to make mulch. Add a three-inch layer of mulch under trees (a few inches away from the trunk to minimize rot) and to planting beds to enhance soil fertility and reduce water needs.

Reduce your garden’s energy needs by reducing the use of electricity and gasoline-powered tools. Consider switching to LED bulbs or solar-powered path lighting and water features. Use battery-powered or (even better) human-powered tools.

For more information about climate-proofing your garden, check out the UCCE Central Sierra Master Gardener webpage at: https://ucanr.edu/sites/MG_of_CS/Gardening/Water_Saving_Tips/ . Call 209-533-5912 in Tuolumne County, 209-754-2880 in Calaveras County or look for us on Facebook.