Welcome to the Land of El Sol

Gardening in the desert is easy. There are so many plants and animals that love it here. Just remember that the air is dry and the sun is hot.

Desert Gardening Success - 5 Easy Steps

Welcome to growing a garden in one of the most fascinating and diverse places on earth – the Southwest desert region. First and foremost you will need to understand what desert gardening zone you live in.

The Desert is Diverse!  There are many different growing zones, not to mention the geographic region itself, with strongly upthrusting mountains, windswept plateaus, and canyons that reach down into the dawn of earth’s prehistory. We have elevations close to sea level in Yuma, Arizona (not to mention below sea level in Death Valley) and some of the tallest peaks in the lower 48 states, such as the snow-capped San Francisco peaks outside of Flagstaff AZ, and the Sangre de Cristo Range in New Mexico. Mountains and mesas may be of igneous, metamorphic or sedimentary rock, providing unique parent material for the soils of our region. With this wide geographic variation in the Southwest comes vast climate variation, as much as you could see in a journey from the tip of Florida to the Alaskan tundra! So welcome to gardening in a very unique corner of the world!

Desert Southwest States Defined

Southwest desert growing zones do not respect state boundaries! The material I cover in the The Gardening With Soule Club will include areas in a 15 states in the USA and Mexico. Moving from West to East, the

Southwest includes: 

southeastern California,

Nevada,

southern Utah,

Arizona,

New Mexico,

southern Colorado,

western Texas, and

western Oklahoma.

The analogous regions in Mexico that can also use my classes includes Baja California Sur, Baja California Norte, Sonora, northern Sinaloa, Chihuahua, Coahuila, and northern Nuevo Leon.

Desert Gardening Regions

The Southwest includes areas of desert, plains, and mountains. These can be loosely lumped into either hot or cold “desert” regions. These have changed their names in recent years but are mostly termed: Chihuahuan, Great Basin, Mojave, and Sonoran Deserts and the Colorado Plateau. While most people think of deserts as dry and hot, these deserts also feature notable wet and cold, even freezing periods.

Summertime highs over 100 degrees are common, but winter lows in the teens are also common. Areas that get sufficient hours of cold (called “chill hours”) can grow temperate fruit trees such as apricots and apples. The vegetable growing season is generally year-round, with marked times for planting cool-season or warm-season plants. Many garden favorites such as roses and iris do well here.

Rain for Desert Gardening

In these Southwest regions, there are two marked rainy seasons. Gentle soaking winter rains off the Pacific Ocean grace the Mojave and Sonoran Deserts. Torrential summer thundershowers sweep in off the Gulf of Mexico, and fall upon the Chihuahuan and Sonoran Deserts. Some areas commonly get both rains so that the average rainfall in the intermediate desert region is 2.5 to 12 inches, depending on your location.

Local vegetation varies from dense to sparse. If you plan on watering your garden, at least occasionally, you can grow virtually anything from these three deserts in your garden, along with a plethora of arid-adapted plants from around the world, like Greek oregano, Roman chamomile, Thai basil, or palms from the Sahara.

Gardening Regions in the Southwest

These are the terms I will use in the Membership site!

I developed these simplified gardening regions for the books I wrote for Cool Springs Press. These regions are based on three factors: 1) elevation, 2) USDA hardiness zone, and 3) seasonal rainfall patterns – in other words, your local climate.  Even within these three regions, there is huge variation in growing conditions. Indeed, within your own yard, there are variations in growing conditions, termed micro-climates. You may be able to grow something not rated for your regional climate by using such highly local micro-climates.

Low Desert

May never freeze, but if it does, between 15 November and 15 February.

Summer highs in the 110’s

Average summer humidity 10 to 40 percent

Average winter humidity 0 to 80 percent

Middle Desert

First frost average 1 November

Last frost average 15 March

Summer highs in the 100’s

Average summer humidity 10 to 90 percent

Average winter humidity 0 to 80 percent

Upper Elevations

Averages! – your local area may differ.

First frost average 1 October

Last frost average 1 May

Summer highs in the upper 90’s

Average summer humidity 20 to 70 percent

Average winter humidity 5 to 30 percent

USDA Zones for Gardening In the Land of El Sol Zones

United States Department of Agriculture (USDA) has mapped out the US into Cold Hardiness Zones. In the Southwest, USDA zones range from 10B to 4A – totaling 14 categories.

Rather than tediously referring to these zones, I divide your gardening tasks into Low Desert, Middle Desert, and Upper Elevations.

Low Desert

USDA Zones 10B to 9A – includes Ajo, Alamogordo, Bullhead City, Las Cruces, Parker, Phoenix, Yuma. Some of these cities routinely experience mild winter freezes while others rarely do.

Middle Desert

USDA Zones 8B-7B – includes Alamogordo, Albuquerque, Alpine, El Paso, Gallup, Kingman, Las Cruces, Las Vegas, Lordsburg, Safford, Sierra Vista, Socorro, Tonopah, Tucson, Wilcox. These cities routinely experience moderate to severe winter freezes.

Upper Elevations

USDA Zones 7A to 4A –

includes Carson City, Colorado Springs, Durango, Elko, Ely, Fallon, Flagstaff, Gallup,

Holbrook, Prescott, Reno, St. George, Santa Fe, Sedona, Show Low,

Taos, Window Rock, and

Winnemucca. These areas always freeze in winter, and often experience below zero weather.

There is always an exception!

The exception is – USDA Zone 7B – which includes the cities of Albuquerque, Socorro, and Tonopah. In general, gardeners in 7B should consider themselves an “upper elevation.” The exception occurs when you experience an unusual season, like a warm spring, then you can do “lower elevation” tasks. Every so often I will mention this specifically to remind you. One factor you can’t fudge in 7B are the chill hours certain fruit trees need. You will need to select those with fewer required chill hours, because of those unusual years.

Zones Data Sheet © J. A. Soule.

Do not copy or distribute without permission.


Categories: Desert Gardening Success, Desert Zones