Keep desert plants healthy in Arizona by planting in fall, watering deeply but rarely, setting each crown slightly above grade, and shielding young plants from July heat and January frost. Queen Creek’s caliche and alkaline soil reward that routine.
Key takeaways
- Plant from October through early November, or in late February and March, and avoid June and July.
- Dig the hole 2 to 3 times as wide as the root ball but only as deep, with the crown 1 to 2 inches above grade.
- Water established plants deeply every 7 to 14 days in summer, depending on type, and check that the soil is dry 12 inches down before the next round.
- Spread 2 to 3 inches of mulch and keep it a few inches away from stems and trunks.
- Cover frost-tender plants when the forecast reaches 32°F or lower, and hold heavy pruning until frost danger has passed.
When is the best time to plant desert plants in Arizona?
October through early November is the best window, with late February through March as the second choice. Warm fall soil keeps roots growing while the air cools, so plants have several months to establish before summer highs climb above 110°F. Spring plantings get less time.
June and July are the hardest months to plant. Roots sit in hot soil, and young plants lose water faster than they can absorb it. If a summer planting cannot wait, set it in the ground early in the morning and shade it for the first few weeks. Browse the plants section to see the shrubs, perennials, cacti and succulents we commonly carry, and keep in mind that availability changes week to week and season to season.
What do you need before you start digging?
A sturdy shovel, a digging bar for caliche, a hose, a moisture probe, mulch, drip emitters and frost cloth cover most jobs. A long screwdriver works as a probe.
Dig a test hole 18 to 24 inches deep before you buy anything, because a pale, rock-hard layer that resists the shovel is caliche, and it decides where your water goes. Fill the empty hole with water and watch how fast it drains. Water still standing after a day signals a drainage problem. In that case, break through the caliche with the bar or plant on a low mound.
How do you plant a desert plant in Queen Creek soil?
Dig a wide, shallow hole, set the crown slightly above grade, backfill with native soil and water deeply. The steps below work for most desert shrubs, cacti, agaves and trees.
- Dig the hole 2 to 3 times as wide as the root ball and only as deep as the root ball.
- Roughen the sides of the hole with the shovel so roots can push out into the surrounding soil.
- Set the plant so the top of the root ball sits 1 to 2 inches above the surrounding grade, which protects the crown from rot.
- Backfill with the soil you dug out. Skip compost and potting mix for desert natives, since a rich pocket can hold water around the roots.
- Build a basin of soil 3 to 4 inches high just beyond the root ball.
- Water slowly and deeply, filling the basin twice and letting the first fill drain before the second.
- Spread 2 to 3 inches of mulch over the root zone, leaving a few inches of bare soil around the stem or trunk.
- Place drip emitters at the edge of the root ball, not against the trunk, and move them outward as the plant grows.
New plants usually need water every few days for the first month, then weekly, then every 10 to 14 days as roots spread. Alkaline soil with a pH of roughly 7.5 to 8.5 can lock up iron, and the result is yellow leaves with green veins, called chlorosis. Choosing plants adapted to alkaline soil avoids most of it.
How often should you water established desert plants?
Water deeply and infrequently, then let the soil dry before the next irrigation. Push a probe into the soil a day or two after watering, and wait for the next round if it slides in easily past 12 inches.
The intervals below are starting points for established plants in the East Valley. Soil type, exposure and plant age change them.
| Plant type | Summer interval | Winter interval | Check soil depth |
|---|---|---|---|
| Cacti and agaves | Every 2 to 3 weeks | Monthly or less | 12 to 18 inches |
| Desert shrubs | Every 7 to 10 days | Every 2 to 3 weeks | 18 to 24 inches |
| Desert trees | Every 10 to 14 days | Every 3 to 4 weeks | 24 to 36 inches |
| Flowering perennials | Every 5 to 7 days | Every 10 to 14 days | 8 to 12 inches |
Short, frequent runs of a drip line wet only the top few inches. That encourages shallow roots, which suffer first in heat and wind. Run the system less often and for longer.
How do you protect desert plants from heat and frost?
Shade young plants during the hottest weeks, and cover tender plants on frost nights. Established desert natives need little of either, but plants in their first two years need help.
Summer heat
Shade cloth rated at 30 to 40 percent, draped over stakes, protects young plants and newly planted cacti from sunscald when highs stay above 105°F. Thin-barked young trees can be painted on the south and west sides of the trunk with white interior latex paint diluted about half and half with water. Pick tree species suited to a hot west wall, and the desert trees are a good place to start.
Winter frost
Queen Creek gets occasional winter nights at or below freezing. Cover bougainvillea, citrus, Baja fairy duster (Calliandra californica) and other tender plants with frost cloth in the evening. Remove it the next morning once temperatures rise. Plastic traps moisture against the leaves, so use cloth. Planting tender species against a south-facing wall adds a few degrees of radiant warmth.
What should you do during monsoon season?
Check drainage before the monsoon starts, and inspect for storm damage afterward. The season runs roughly July through September, and a single storm can drop a large amount of rain in under an hour, more than caliche-layered soil can absorb.
Watch where water collects after a storm. Standing water around a trunk for hours can rot roots, even on plants that have done well for years. Regrade low spots or cut a shallow channel to carry runoff away. Skip irrigation after a soaking rain and probe the soil before you restart. Wind and dust can snap branches. Cut broken limbs back cleanly with bypass pruners so torn wood does not invite pests.
When should you prune and fertilize desert plants?
Prune in late February through March, after frost danger has passed, and keep summer pruning light. A plant’s canopy shades its own roots and trunk, so heavy cuts in June or July expose both to full sun.
Frost-damaged growth should stay on the plant through winter, because it insulates the tissue beneath it. Cut it back once new growth appears in spring. Most established desert natives need little or no fertilizer, and extra nitrogen pushes soft growth that pests and frost damage easily. If a plant looks pale or grows slowly, apply a light dose of slow-release fertilizer in spring, following the label. Our gardening calendars help you time seasonal tasks.
Which mistakes shorten a desert plant’s life?
Most losses trace back to a handful of habits, and all of them are easy to fix.
- Planting too deep. A buried crown holds moisture against the stem and invites rot.
- Watering a little every day. Deep, infrequent irrigation builds deeper roots.
- Over-amending the hole. Native soil works best for most desert plants.
- Pruning hard in summer. The canopy protects roots from heat.
- Ignoring microclimates. A south or west wall can run 15 to 20°F hotter than the north side of the house on a summer afternoon.
Frequently asked questions
Why are my desert plant’s leaves turning yellow?
Uniform yellowing with damp soil usually points to overwatering, while yellow tissue between green veins on new growth points to iron chlorosis from alkaline soil. Let the soil dry deeper before the next irrigation. For chlorosis, a chelated iron product used according to its label can help, though adapted plants avoid the problem.
Is decomposed granite or bark better for mulch?
Decomposed granite suits cacti, agaves and shrubs because it does not break down, while bark or wood chips suit trees and perennials that benefit from slow organic matter. Apply either at 2 to 3 inches deep. Keep it a few inches from trunks and stems so moisture does not sit against the bark.
How long until a new desert plant is established?
Most shrubs need one to two years of regular care, and trees often need two to three. Established means the plant handles the schedule in the table above without wilting or stress. Until then, check the soil often, especially during the first summer, and keep young plants shaded during extreme heat.
Where can I learn more in person?
Our classes and events page lists upcoming gardening workshops at the nursery. Bring photos of your yard, a note on which direction your beds face, and any questions about soil or watering, and our staff can help you plan.
Is a desert garden right for your yard?
A desert garden suits you if you can water on a deep, infrequent schedule and accept a more open, sculptural look than a lawn gives. It does not suit you if you want lush, green growth on daily watering, or if your irrigation timer runs on autopilot and you rarely check it. Start with a few adapted plants in one bed, learn their rhythm, and expand from there. Stop by our Queen Creek nursery and we will help you choose.
