Predictions of a warmer winter notwithstanding, frosts and freezes in Southern Arizona are normal and expected for the season. They can occur as early as late November.
Chances for plant survival increase in these weather conditions if you can raise the temperature around the plant and avoid drying wind and prolonged freeze.
Two landscape designers provide tips on how to get your plants through winter conditions.
Start protecting now by "hardening" plants, recommends Shelly Ann Abbott, owner of Landscape Design West.
"Start dialing back on the drip irrigation," Abbott says. This will stop growth that a frost or freeze can easily damage.
Have a light cloth or special frost cloth ready to cover plants, say both Abbott and Jason Isenberg, owner of Realm, a landscape design and maintenance company.
Isenberg suggests what his company does: Build a structure around a large plant over which you can better drape cloth.
When a frost or freeze is predicted, put movable plants in protected areas overnight, such as deep within patios and carports or inside garages or homes, Abbott says.
Micro-sites, those places around the house that differ from general conditions, can work to keep plants protected. Even a temperature difference of a couple of degrees can affect a plant's health.
For instance, south- and east-facing walls block wind and add evening warmth that the walls absorb during to day and release after dark.
With the sun low in the sky, patios and overhangs give plants plenty of sun along with wind protection.
Use other plants to protect cold-sensitive ones. Abbott suggests planting under mature trees that can provide a protective canopy. Isenberg likes to put a cold-sensitive plant next to a cold-hardy one that can act as a wind break.
Because cold air sinks, plants may stay warmer if they're elevated instead of in a basin, Isenberg says.
Plant away from any dips such as a wash, which holds cold air for several hours.
It's late now to get cold-sensitive plants acclimated in your yard, but for future reference, here are some ideas for selecting what might survive in your micro-climate:
• If saguaros and ironwoods are growing naturally in your area, then you live in a warmer micro-climate that can encourage some cold-sensitive plants, Abbott says.
• Cold-sensitive plants also do better in urban areas with tall buildings, parking lots and other infrastructure that retain more heat, she says.
• Opt for dwarf or modest-sized citrus trees. "The larger the citrus, the harder it is to cover when it's cold," Isenberg says.
• Also consider kumquat and limequat as alternatives to other citrus trees. "They're the most cold tolerant of all citrus," he says.
Did You Know?
"Frost" and "freeze" are different.
Frost occurs when the air temperature is above freezing while surfaces, including plants, are below freezing.
Freeze happens when air and surface temperatures reach 32 degrees.
Source: Mick Sherwood, meteorologist, Tucson National Weather Service Forecast Office.
Contact local freelance writer Elena Acoba at firstname.lastname@example.org