At higher elevations, frost has already put down many plantings for their long winter's nap. Lower elevations, like Phoenix, will see frost by mid-month.
In all locations, as freezing temperatures come and go, you can prolong the growing season by protecting plants.
- Start by monitoring weather forecasts online so you can prepare for cold snaps. This is especially vital in areas where frost comes and goes throughout the winter.
- If frost is predicted, cover plants you want to preserve with a sheet, burlap, or other nonplastic material. Remove covers after the sun is up and temperatures have risen sufficiently.
- You can purchase frost blankets that guarantee protection to a specific temperature. Frost blankets are typically permeable to water, air, and a portion of sunlight, so they can be left in place for a few days, if necessary.
Move outdoor potted tropicals to a protected spot on a porch or covered patio if frost threatens. For tropical succulents, like desert rose (Adenium obesum), keep plants under cover through winter to protect from seasonal rains.
Test Garden Tip: Frost helps some vegetables -- like Brussels sprouts, kale, and carrots -- develop better flavor. Many leafy greens, including spinach and lettuce, withstand hard frost (below 28 degrees F).