February Garden Checklist
Learn what to plant this month, get maintenance advice and troubleshoot your gardening challenges with an expert.
By Kelly Young
What to Plant
COOL-SEASON VEGETABLES–Sow seeds of leafy green kale, Swiss chard, arugula, spinach, leaf lettuce, collard greens and root vegetables, such as radishes, carrots, turnips and beets. To keep aphids and other insect pests at bay, protect new plantings with floating row covers, which are available at most garden centers.
TOMATOES–Transplant tomatoes into beds where they will have plenty of space to stretch out. Allow at least 2 to 3 square feet per plant. Select healthy plants with deep green leaves that show no evidence of leaf curling or pest damage. Tried and true ‘Better Boy’ is a tasty slicing tomato with large red fruits. For something a bit more exotic, look for ‘Indigo Rose,’ a variety that produces small black fruits that are unlikely to split open and be ruined.
TREES, SHRUBS AND WOODY VINES–For a hardy tree that does well in urban landscapes, try live oak cultivar ‘Joan Lionetti’
(Quercus fusiformis ‘Joan Lionetti’), developed by Civano Nursery and named for the founder of Trees for Tucson, a project that promotes planting shade trees in Tucson and eastern Pima County. This drought-tolerant evergreen is fairly compact for an oak, reaching only 20-30 feet in height and spread. White plumbago (Plumbago scandens) is a shade-tolerant shrub that will quickly grow to a mature size of 3 feet tall and wide. And for a spectacular show of pink flowers in the fall, try pink trumpet vine (Podrandea ricasolilana), a sprawling, low-water-use vine that reaches a height of 20 feet when supported by a trellis. Dig the planting hole about 1 foot away from where the trellis will be installed, so that the vine’s trunk doesn’t interfere as it thickens with age.
COOL-SEASON VEGETABLES–Sow seeds of kale, leeks, mustard greens, head lettuce, green onions, spring peas and spinach directly into garden soil. Start pepper and tomato seeds indoors for transplanting in April. To guard against fungi and disease, use sterile potting soil and containers for starting seeds.
WILDFLOWERS–Dazzle the neighbors and support pollinators by spreading native wildflower seeds. Firewheel (Gaillardia pulchella), desert beartongue (Penstemon pseudospectabilis) and scarlet bugler (P. barbatus) will attract hummingbirds to your yard.
COOL-SEASON VEGETABLES–Sow seeds of cabbage, cauliflower, Brussels sprouts, chard and kale indoors for transplanting outside in April.
HOUSEPLANTS–Surprise your valentine with miniature roses. Proven high-elevation cultivars include ‘Cutie Pie,’ loved for its pink and yellow blooms, and ‘Beauty Secret,’ a traditional Valentine’s Day red-petaled choice. Enjoy the variety of colors and fragrances these petite favorites bring to a bright windowsill while winter temperatures make outdoor gardening challenging. After mid-March, transplant rose bushes outside.
BUILD SOIL HEALTH–Healthy soils have good water-holding capacity, resist erosion and support a diverse community of organisms that benefit plant roots in ways we are barely beginning to understand. To boost the health of your garden soil, follow these basic principles:
- Add organic matter. Compost, manure and leaf litter are all great sources.
- Minimize soil disturbance. Only till when necessary and avoid activities that compact the soil.
- Keep soil covered using mulch or living plants. Bare soil is prone to wind and water erosion.
FEED CITRUS–Apply one-third of the annual nitrogen fertilizer requirement to citrus trees that have been in the ground for more than one year. For trees less than 4 feet tall, 0.5 – 0.75 pound of ammonium sulfate will do the job. Medium trees 4 to 8 feet tall need about twice that amount. Give mature trees 2 pounds. Follow up with a deep watering to dissolve the fertilizer and carry it to the tree’s roots.
MANAGE WEEDS–If winter rains resulted in a flush of weeds in your landscape, get after them before they set seed. Warmer, drier temperatures that will arrive in March will kill most cool-season weeds, such as London rocket and sowthistle, and send the insect pests they harbored into your garden in search of a new food source. Use a string trimmer or hoe to chop unwanted growth to ground level or pull them by hand. If you must spray, select a contact herbicide that is labeled for use on the species you are trying to manage.
PRUNE DORMANT DECIDUOUS FRUIT TREES–Take advantage of the great view that winter leaflessness provides to manage plant size and let light into the center of the canopy of apple, peach, apricot, persimmon and other deciduous fruit trees. Use clean, sharp tools and avoid using “pruning paint,” which tends to trap pathogens inside the wound and interferes with the plant’s own ability seal the cut naturally. Learn more about pruning deciduous fruit trees by viewing videos from the University of Arizona Cooperative Extension (cals.arizona.edu/yavapai/pruning/videos.html).
REMOVE DEAD PLANTS–Standing dead trees, particularly pines, can be highly flammable and sometimes harbor wood-destroying beetles. Cut down dead trees and grind them into mulch that can be distributed to suppress weeds and improve the water-holding capacity of the soil by reducing evaporation and adding organic matter. Most tree companies are happy to leave the wood chips on your property and avoid a trip to the landfill.
Can we use the backwash from our swimming pool to water the lawn?
In addition to the various chemicals that help to keep pool water clear, backwash is frequently loaded with substances that can cause injury to plants. Arizona tap water tends to be salty, and as water evaporates from the pool into the atmosphere, the salts stay behind. Each time more water is added to the pool to compensate for evaporation, the amount of salt is inadvertently increased. Although you can use the backwash to irrigate the lawn, it’s best not to make it a regular habit. The accumulated salts will persist in the soil and damage sensitive turf and other landscape plants that have roots in the lawn. Bermuda grass is fairly salt-tolerant and probably will not be hurt too terribly by exposure to the backwash every other year or so.
I’ve been trying to start vegetable seeds indoors to plant outside this spring, but the seedlings get moldy and die a few days after germinating. I’ve been starting seeds successfully for many years, but my luck seems to have run out. What went wrong?
Rapid wilting and death of young seedlings is called “damping off” and can be caused by one of several soil-borne organisms, such as Pythium, Fusarium or Rhizoctonia. These species thrive in cool, moist conditions and may accumulate in seedling flats and potting soil that has been re-used year after year. Start over with new sterile soil and containers or disinfect all flats, pots and tools with a solution made by diluting one part chlorine bleach with nine parts water.
My homeowners association needs to replace several evergreen elms that died last summer. Is it okay to replant elms, or should we try something different?
Before you replace the dead elms with anything, your HOA should determine what caused the original trees to die so it doesn’t happen again. Elms are susceptible to soil-borne disease called phymatotrichopsis root rot or Texas root rot. If you plant more trees in the same location as the dead ones, they will most likely die of the same disease if it is present in the soil. Other causes of death that your HOA should consider include irrigation problems or the consequences of planting too deeply. Understanding that many HOAs are cost-conscious, hiring a certified arborist to get to the bottom of the tree deaths will be far less expensive than losing your investment to another round of trouble. Find a certified arborist by visiting the International Society of Arboriculture’s webpage at www.treesaregood.org/findanarborist.