Don’t Put Away Your Tools Just Yet: Your December and January Garden Checklist

Jump directly to tips for:

• All Regions
• Northwest
• Rocky Mountains
• Northern California
• Southern California
• Southwest

All Regions

Plant

For a truly low-care houseplant, grow canna lily, sweet flag (Acorus calamus), or umbrella plant (Cyperus alternifolius) in a waterproof container. Drop the nursery pot into a container and keep the outer container filled with several inches of water. Fertilize the plant once a month, and rinse and refill the outer container every two weeks to keep the water from becoming rancid. 

Succulents and sedums are easy to propagate from any pieces that break off from the parent plant. Allow the leaf or segment to dry for a few days and then lay on moistened perlite in bright, indirect light. When roots or new leaves appear, transplant into a small pot filled with a potting mix formulated for cactus and succulents. 

Maintain

To make fast work of winter pruning, use good bypass pruners (like Felco 2) on everything smaller than your thumb, and a hardened, tri-edged folding saw (like an 8.3-inch Silky Gomboy with large teeth) on branches. 

Fertilize established stone fruit trees with a granular organic fruit tree fertilizer. The label will tell you how much to use, based on tree size. 

Reward yourself with a pat on the back. Every triumph you had in your garden over the past year should be celebrated, before you look to the year ahead. 

Northwest

Plant

To grow a lot of perennials for little money, start them from seed this month. Sow aster, delphinium, hellebore, Shasta daisy, or viola seed in a greenhouse or cold frame, then transplant into your garden in April. 

Maintain

To remove a large branch, cut through the bottom third of it, 12 inches from the trunk; then saw it off 2 inches beyond the first cut. Finally, cut the stub off just outside the branch collar. 

Smother weeds and retain nutrients by top-dressing beds with a layer of leftover compost or other mulch. 

More from this issue:

• 2021 Sunset Travel Awards: 75 Ways to Experience the West
• A Renovated A-Frame Near Lake Arrowhead Builds the Case for a Pink Front Door
• How the First Family of Fish Sauce Does a Holiday Feast

Subscribe now!

Protect

If your garden gets steady wind, plant an evergreen windbreak at least 10 times as wide as it is tall. It can protect up to 30 feet of downwind land for each foot of its own height. 

Snow makes the garden look like a fairyland, but it also disfigures woody plants. Sweep snow off branches right away and plants should recover. 

Rocky Mountains

Plant

If tropical houseplants are struggling when the thermostat is lower, try azalea, cyclamen, carnation, hydrangea, and lilies. All can do well when nighttime temperatures drop to 50° to 60°. 

Sow warm-season edibles indoors for transplanting into your garden in May. For something new, try the Colorado Red Star artichoke from Baker Creek Heirloom Seeds. 

Maintain

Prune deciduous trees by removing branches that are dead, cross through the middle of the tree, or rub up against one another, along with any suckers growing from the base. 

Azalea, boxwood, holly, Oregon grape, and rhododendrons are prone to winter drought damage. Monitor throughout the winter and soak thoroughly whenever the soil dries out. 

To keep roots safe from frost, wind, and drought, replenish bare patches where organic and rock mulch have blown or washed away. Hay, leaves, and straw protect plants best when they’re 6 to 8 inches deep; keep bark and rock mulch 2 to 3 inches deep. 

Northern California

Plant

Browse nurseries for bare-root berries, grapes, and roses. Once you get them home, unwrap any plastic around the roots and put the plants in a bucket, then cover roots loosely with potting soil. Water enough to prevent soil from drying out until you’re ready to plant. 

Refresh the vegetable garden by sowing seeds of broccoli, cabbage, cauliflower, lettuce, and mustard. Plant onion sets, which look like small bulbs, just under soil surface so the point of the bulb is visible. 

Maintain

Sprinkle granular organic fertilizer, according to package instructions, around the bases of established fruit trees out to the canopy drip line. Rain will help the fertilizer percolate into the soil. 

Pick up fallen camellia blossoms. Leaving them at the base of the shrub encourages disease. 

Harvest

Pick ripened citrus as you need it. Leave unripe fruit to hang; it won’t get sweeter once picked. Dry out fruits you don’t intend to eat for a citrus garland or place them among cut boughs for a festive holiday table or hearth. 

Southern California

Plant

Keep your veggie garden producing by sowing seeds of kale, leek, lettuce, mustard, green and bulb onion, parsley, pea, radish, spinach, and Swiss chard. Inland, choose varieties that will withstand frost, including thick-leafed lettuce, flat-leaf parsley, and savoy spinach. 

Maintain

Divide and replant any over-crowded perennials, including Agapanthus, chrysanthemums, and daylilies. To reduce shock from the move, water plants before and after planting. 

Winter rains can be unpredictable. If they’re light, continue to irrigate plants when the soil dries out. Also frequently check containers and plants growing under eaves where rain doesn’t reach to make sure they’re getting enough water. If rains are adequate, turn off the irrigation system’s automatic controller (or install a rain shutoff to do it for you). 

Southwest

Plant

Boneset (Conoclinium greggii) is the low-growing perennial for attracting queen butterflies (Danaus gilippus) during the warm months. Provide boneset with moderate irrigation and cut back in late spring for best summer appearance. 

If you have aloes with pups, pot them up in cactus soil mix in small containers and put them indoors in sunny windows. That way, you’ll have some aloes that will bloom in early spring (and ready replacements for any outdoor plants that may get damaged by frost). 

Maintain

To foster fresh growth, prune the woody stems on herbs like oregano, rosemary, and thyme. You’ll thank yourself come spring. 

Check drip irrigation systems for leaks or kinks. Open the ends of drip lines and run the system for a few minutes to flush or install self-regulating auto-flush valves.