Every desert gardening book recommends October as the prime month of the year for planting. By now plans should be made, resources checked out, and maybe even a few plants or seeds purchased. Planting at this point allows time for development of a sturdy root system before the plants’ first hot summer. With cooler autumn temperatures, new plants also escape any drying hot winds while recovering from transplant shock.
The average date for the first frost this season is in late November, so there is still time for plants to become established before cold weather may appear. Keep in mind that native and desert-adapted plants are easiest to care for and the least demanding.
For vivid winter color, it is time to start setting out transplants of your favorite annuals. For either the garden or containers, first consider the tried-and-true: pansies, violas, petunias, sweet alyssum, stock, and calendula. Most of these flowering plants survive or even thrive with little or no cold protection during our commonly mild desert winters.
If perennials are preferred, there are: blackfoot daisy, chuparosa, Mt. Lemmon marigold, fairy duster, moss verbena, chocolate flower, or any of the many colorful salvias. For a large space, check out accent plants and small shrubs such as: desert spoon, woolly butterfly bush, black dalea, creosote, or any number of agaves and prickly pear options. Among even larger shrubs, consider Arizona rosewood, hop-bush, Texas mountain laurel, jojoba, yellowbells, aloysia, or cassias.
Nearly all types of cold-hardy groundcovers, shrubs, trees and vines develop strong roots and thrive when planted this month. Trees included are cultivars of Texas ebony, palo verde, hackberry, sweet acacia, mastic, and desert willow. However, do not plant palm trees which do not accept cool soils; wait until May.
If your interest is vegetables, there is still time to set out transplants of broccoli, kale, cabbage, cauliflower, shallots, and onion sets. Plant seeds of Swiss chard, spinach, radishes, arugula, and any of various lettuce types.
For drip irrigation systems, as temperatures cool reset the controller so watering is done less frequently. However, the duration of each cycle should remain the same throughout the year. A 4-inch layer of mulch around plants will help conserve moisture, insulate roots, and discourage winter weeds. Oh yes, there are winter weeds in the desert!
A world of garden options will be available for your choosing at Green Valley Gardeners’ Annual Fall Plant Sale on Oct. 24 through 26, starting at 9 a.m. each day. This major fundraiser held in the shady, northeast corner of Continental Shopping Plaza supports a number of local community outreach projects. Bring your garden ideas and stop to pick up a burst of autumn planting enthusiasm!
Mary Kidnocker is a University of Arizona Master Gardener who lives in the Green Valley area. Her articles are featured weekly.