December Gardening and Landscaping Tips

Cindy Mayhle, Maintenance Manager for AAA Landscape

Here are this month’s tips for keeping your trees, shrubs, flowers, and plants healthy.

Prepare for Frosts Now

If you don’t care for your sensitive trees, bushes, flowers, and vegetables before the first frost, it’s probably too late, since the first frost will permanently damage them. It is not uncommon to have up to 20 frosty mornings in December. Be prepared to cover those frost-tender plants throughout December.


Your over-seeded winter lawn should be established by now.

• If your winter lawn turns yellowish, fertilize. An application of Ironite will bring back the dark green color.

• Water every five to seven days, or more often if you notice the soil drying out. Light or sandy soils dry out faster.

Trees and Shrubs

Wrap the trunks of young citrus and other cold-tender trees with cloth, cardboard, or several layers of newspaper (no plastic) to protect them from frost. Leave them wrapped until the threat of frost has passed.

• Sweet oranges, navels, lemons, tangerines, and tangelos may be picked now, but pick only as needed. As the season wears on, the fruits will continue to sweeten.

• Citrus fruit stores best on the tree.

• Frost-tolerant trees and shrubs may be planted this month. Dig holes three to five times the size of the root ball, but not any deeper. Set the plant so the top of the root ball is ground level and then backfill.

• Remove dead branches and water sprouts.

Christmas Trees

When you purchase your tree, try to get a freshly cut tree. Feel the needles for dryness; the needles should be pliable. Cut an inch off the trunk, put it in a stand with a water reservoir, and fill it daily. If you buy a living tree, don’t bring it inside until about a week before Christmas and take it back outside right after the holiday. After the tree has been outside for a while and is again acclimated to the colder weather, you can plant it or donate it to a school or park.


• Plant seeds: beets, broccoli, cabbage, carrots, cauliflower, garlic bulbs, green onions, leeks, lettuce, parsley, peas, radishes, Swiss chard, spinach, and turnips.

• Plant transplants: asparagus, broccoli, cabbage, cauliflower, lettuce (head & leaf).

• Asparagus is best planted in a single row.


Flowers can still be planted, so choose your favorite annuals and perennials.

You can still plant bulbs. Plant them in well-drained soil that is also high in compost or organic matter. Your bulbs should be planted with about two inches of sand beneath them. Cover with a coarse material such as peat moss or crushed wood products, such as bark.

Chrysanthemums begin to die back after blooming.

Cut back dead or dying foliage and add a bit of nitrogen fertilizer.

Poinsettias will turn yellow if you water them with the foil sleeve still on because they will sit in the water. Take them to the sink, remove the foil sleeve, water until water comes out the bottom, let them drain for a few minutes, and then put the foil sleeve back on.

Start getting the new rose catalogs and watch for bare root roses at nurseries later in December. Get your seed catalogs too and start ordering!

Your Desert Garden Monthly DON’T List for December

• Don’t pick grapefruit yet. Grapefruit are the best in late spring or early summer.

• Don’t fertilize trees or shrubs in December. Wait until spring.

• Don’t over water.

• Don’t ignore pest problems.