Compiled by Master Gardeners – Amanda Steves and Ann Smith
Here’s a list of December garden tasks for the Texas Coastal Bend area from the Aransas/San Patricio County Master Gardeners.
— When a freeze is predicted, be ready to protect your tender plants and trees. Keep a pile of sheets and blankets ready to throw over them.
— Decide ahead of time where you will move your vulnerable potted plants for cold weather, and clear out some space. A garage is good, but if you don’t have one, any place that’s semi-protected is better than nothing—a covered porch or carport, under the eaves on the south wall of the house, even under other bushy trees and shrubs.
— Add mulch on your flower beds regularly—it can be up to 6 inches deep, but keep it off the stems and trunks.
— Water your lawn, trees, and landscape plants ahead of freezing temperatures to help the soil hold its heat.
— December is a good month to cut down problem trees that may be growing in your yard. If you have invasive species such as Brazilian pepper trees, chinaberry, or tallow trees, you’ll be doing yourself and everyone else a favor by taking them out now.
— Check your trees for mistletoe—it’s a branch-killing parasite with poisonous berries. Simply cutting it off stimulates more growth. The only way to eradicate it is to remove it along with the branch, cutting at least 1-2 feet in from the attachment point to get the interior roots of the mistletoe.
— This is an excellent time for planting non-tropical trees and shrubs.
— Clean your garden tools well. Rinse them off with water and remove the remaining gunk with a little oil or WD-40 and some steel wool. You can sharpen the working edges of large tools with a file and use a small sharpening stone or diamond dust stone for pruning shears and smaller blades. Then give the metal a light coat of oil or WD-40 to prevent rust, and store in a dry place. Because of our humidity, unprotected tools can rust even in a garage.
— Indoor poinsettias, succulents, and Norfolk Island pines need a little bit of water every day because of the dry, heated environment.
— Let your indoor amaryllis and Christmas cactus dry out an inch or two below the soil surface between waterings.
— You can keep most holiday plants throughout the year in their pots indoors or plant them outside. Christmas cactus, however, will not tolerate temperatures below 50 degrees F, so keep it indoors.
— December is the month to start picking citrus fruits. Many will be ripe enough to eat, but the longer they stay on the tree during non-freezing cold weather, the sweeter they will get. You can leave them until just before the tree blooms in March unless there’s a hard freeze.
— If a hard freeze is predicted, pick all of your citrus fruits ahead of it. Fruit on the tree can tolerate overnight freezes down to about 26 degrees F.
— If you have small citrus trees, protect them from freezing by covering them all the way to the ground and securing the edges with bricks or rocks. This will help trap the heat radiating up from the ground.
— You can still plant winter garden crops like broccoli, cauliflower, radish, kohlrabi, mustard greens, and turnips. They can withstand a light freeze, and they will be well-established and producing by March.
— Don’t fertilize your grass—it’s too late.
— You can apply an herbicide to your lawn to control winter annual weeds like vetch and burr clover. Be sure to use a product that lists the weeds you want to control, and follow directions carefully.
— Lightly water your lawn if a couple of weeks go by with no rain.
— If you have pansies, chrysanthemums, snapdragons, dianthus, lobelias, stock, or violas, they will most likely keep blooming right up until March. You can even plant them this month if you find them at the nursery.
Thanks to Master Gardeners Ann Smith, Fred Alexander, Todd Cutting, Jeanna Godfrey, and Barb McSpadden for contributing to this list.
Master Gardeners is a non-profit program of Texas A&M Agrilife Extension Service. Our education programs serve people of all ages, regardless of socioeconomic level, race, color, sex, religion, handicap or national origin.
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