December 2023/January 2024 Garden Checklist and Solutions
What to plant, prune and pluck this winter according to your elevation.
Pomegranates thrive in the desert heat and offer a different look throughout the year. Bright, orange-red blooms appear in spring, followed by leathery fruits filled with juicy, edible seeds. The foliage turns gold in autumn, before falling off for winter. Cultivar ‘Wonderful’ is a popular choice, thanks to its reliable production of large, red fruits with tart, burgundy seeds, or arils. Another option to consider is ‘Parfianka,’ rated one of the best-tasting pomegranates with small, deep-red seeds. Or try ‘Pink Satin,’ a sweet variety with light-colored seeds that won’t stain surfaces or fabric.
many types of vegetables can be grown now. Greens and root crops such as beets, carrots, radishes, turnips, green onions, arugula, leaf lettuce, chard and spinach can be planted from seed directly into garden soil. Sprout tomato seeds indoors in early January to move outdoors once they have 4-6 true leaves. Start broccoli, cauliflower, cabbage, head lettuce and artichokes from transplants to give them enough time to produce before spring turns up the heat. Asparagus can be purchased and planted as dormant crowns now. Asparagus is a perennial crop that will continue to produce spears year after year, so plant them in a permanent location and give them plenty of room to spread over time.
If you are planning to grow tomatoes from seed this spring, start shopping for seeds now to start indoors in January. Look for ‘Tye-Dye,’ a yellow-and-red slicing tomato that is low-acid and sweet. For a snacking type, try ‘Texas Wild Cherry,’ a prolific, early-maturing variety.
Spice up your life and salads with fresh herbs and edible flowers. Sow seeds of annual cilantro, parsley, chives, borage, nasturtium, calendula and dill into garden soil or containers. Transplant perennial oregano, mint, catnip, lemon balm, lemon grass and thyme. Mint tends to take over garden beds, so consider containing this vigorous spreader in a pot.
Before buds break into new shoots, cut back roses to canes approximately 18 inches long. Hard pruning at the end of dormancy will encourage vigorous new growth and blooming. Dispose of cut stems; they may serve as a hiding place for pests if left nearby. Water roses after pruning.
During winter, established, drought-tolerant trees and shrubs need to be watered at least once per month, even if they are leafless and dormant. Non-natives may need to be watered more often. Apply water slowly enough so it doesn’t run off, and let it run for a long enough period that the water percolates to a depth of 3 feet for trees, 2 feet for shrubs and 1 foot for turf and garden beds. A thin, sharp probe will easily penetrate moist soil and stop when it reaches dry soil. A perforated, or “soaker” hose, placed in an undulating ring just outside of the edge of the plant’s canopy can be left on for several hours to slowly hydrate the root system.
Before transplanting a potted holiday tree, gradually acclimate it to outdoor living. Place the tree, still in the container, in a shady location outside for a week, watering it daily. Select a sunny location that will give the tree ample room to grow. Colorado blue spruce, (Picea pungens), a popular living tree at higher elevations, can reach more than 70 feet in height, with a spread of 25 feet. Lower-elevation trees, such as Afghan pine, (Pinus eldarica) grow to 40 feet tall and 30 feet wide. Dig the planting hole 2-3 times wider, but no deeper than the root ball. Backfill with original soil, using water to settle and remove air pockets, which can cause the roots to dry out. Irrigate weekly for the first year, expanding the area water is applied as the tree canopy spreads.
When de-icing walkways, select plant-safe options rather than using rock salt, which contains toxic levels of sodium. Also, steer away from using fireplace ashes, which are too alkaline to be added to arid Western soils. Sand spread on top of frozen surfaces will improve traction but will not melt the ice. There are ice-melt products on the market made of beet juice, which is less toxic to plants but may harm aquatic insects if it reaches bodies of water through run-off. Alfalfa meal powder, which is marketed as an organic fertilizer, is plant-safe and easy on pet paws.
Knock accumulated snow from tree limbs to prevent them from snapping under the weight. If a limb does break, remove it entirely using proper pruning technique. Do not leave a stub, and do not cut flush against the trunk. Avoid stripping the bark when cutting, as this will impair the tree’s ability to recover in the spring. For advice on making a good pruning cut, visit the National Arbor Day Foundation’s website at arborday.org/trees/tips.
Middle and High Elevations
Winter’s cold, windy weather stresses perennial vines, shrubs, grasses and trees. Use irrigation to supplement natural precipitation once in December, ensuring the water penetrates to a depth of 1 foot for grasses, 2 feet for vines and shrubs, and 3 feet for trees. Apply the water around the drip line of the plant, the area that corresponds to the outermost tip of the branches or canopy, where rainfall is naturally channeled and there is a concentration of absorbing roots.
An indoor chrysanthemum that was given to me as a gift was covered in fine spiderwebs, so I immediately threw it out. Now, several of my houseplants are looking sickly and have webs on them. I didn’t think spiders would attack plants. What’s going on?
You are correct that spiders do not attack plants, but their tiny arachnid cousins, spider mites, are serious plant pests, indoors and out. You were wise to quickly eliminate the source. Carefully inspect all remaining houseplants for webbing. Because spider mites are so small, they are hard to detect with the naked eye. Use a magnifying glass to inspect the undersides of leaves or shake plants over a white sheet of paper and watch for moving specks. Quarantine any infested plants in a separate room, and wipe their leaves with a solution of water and insecticidal soap, available at garden centers. Consider discarding any heavily infested plants as they may not recover anyway.
I was given an amaryllis kit as a gift but I will be traveling soon and don’t want to miss the bloom. Can I wait a few weeks before I plant it?
As long as there isn’t a green shoot emerging from the bulb, it is still dormant, and you can store it in the refrigerator for a few weeks until you are ready to plant it. The soil it came with may have dried out, so mix water into the soil to be sure it is thoroughly moist, without being waterlogged. Place the bulb, pointed side up, in the soil, leaving the top one-third of the bulb exposed. Place the pot in a sunny window and water regularly so the soil remains consistently damp. In a week or two you should see the shoot emerge, followed by a beautiful bloom a few weeks after that.
I’d like to grow poinsettias in my garden but I haven’t had any luck getting the plants I buy for the holidays to survive outdoors. Can I grow them outside year-round?
For the best results, try growing a different type of poinsettia. Desert of summer poinsettia (Euphorbia cyathophora) is an annual wildflower that grows easily from seed in the warm Southwest climate. Although its colorful red bracts are not as large and showy as those displayed on the ubiquitous holiday variety, they can add a lovely holiday dimension to flower beds. Be advised that like their popular cousins, desert poinsettias, produce a milky latex sap that is toxic to animals and can be a skin irritant.