WHAT TO DO IN DECEMBER
Protect tender plants during freezes. Use sheets, blankets, or specially-designed row cover. Construct a cold frame or a "hoop house." Mulch, mulch, mulch! Water well before a freeze (except for prickly pear cactus). Allow hardy perennials to freeze back, and do not prune them until late winter or early spring, if you can stand it. The dead structure of the plant helps to insulate and protect the living core of the plant, and is part of the winter landscape. In addition, any pruning can stimulate tender new growth, which would be susceptible to subsequent freezes.
Last chance to plant bulbs. It is best to plant them early this month.
Plant flower/ornamental seeds. Delphinium, Larkspur, Poppy
Plant vegetable plants. Arugula, cabbage, chard and other greens, lettuce, spinach
Plant strawberries. Spinach is a great companion plant for strawberries.
Plant herbs. All hardy perennial herbs such as lavender, oregano, rosemary, rue, sage, and thyme; other cold-hardy annual or biennial herbs like parsley, cilantro, dill, and fennel (Dill and fennel may need some protection during freezes).
Plant annual flower/ornamental plants. Sweet alyssum, bluebonnet plants, ornamental cabbage and kale, Dianthus, Johnny jump-up, pansy, snapdragon, stock
Plant hardy perennial plants. Some examples are agapanthus, damianita, most ferns, Mexican bush sage, Russian sage, trees, and shrubs. It is especially important, if you haven't done so already, to plant spring-blooming perennials such as columbine, coreopsis, ox-eye and shasta daisies, Salvia greggi, and wallflower.
Plant ground covers and borders.
Prune, if necessary. Hire a reputable arborist or study a good, current pruning book before tackling important pruning jobs. If the pruning book is teaching the "flush cut" method, it is teaching an outdated and detrimental pruning method. If the pruning book is written by or refers to Dr. Alex L. Shigo and recognizes the branch collar, you are on the right track. Dr. Shigo's research, along with improving upon the flush cut, also showed that pruning paints are not necessary and may impede the healing process.
Fruit trees have specific pruning requirements for highest productivity and ease of harvest. Again, a reputable fruit tree pruning guide should be consulted ≠ literally from day one of planting.
NEVER "top" a tree, which is pruning back the main leader (or trunk) of a tree, except for certain fruit trees. Topping has also come to mean that awful practice of harshly pruning back some if not all of the branches back to the main trunk. Natasha, the Rose Queen of The Natural Gardener, calls this "poodle-dogging"the tree. Please don't trim back the crape myrtles harshly, either. This is unfortunately so prevalent that it has a name: Crape Murder.
We don't know exactly how these practices got started. I've been told that the practice of topping stems from the need for firewood in olden days. However, they are not necessary; they ruin the beauty of the tree's natural structure; they stress the tree, thus promoting more disease. Trees are so valuable in the landscape that extreme care should be taken to preserve their health.
Spray fruit trees. None of our most common fruit trees are native. Therefore, they need more care than, say, a yaupon holly or a bur oak. To keep apple, pear, peach, and plum trees healthy, and to get the best fruit, these fruit trees need to be put on a spray schedule. (The four trees above are all in the rose family; this may explain why they need more pampering. Figs, pomegranates, and persimmons and the like do not need a spray schedule).
Fruit Tree Spray Schedule for Apples, Apricots, Peaches, Pears, and Plums
At leaf drop in the fall: Spray Actinovate or Serenade to help prevent diseases.
During winter dormancy: Spray Dormant Oil once. Or spray Organocide once a week for 2-3 wks.
At bud swell in late winter/early spring: Spray Actinovate or Serenade.
If plum curculio has been a problem, late winter is the time to control them. Plum curculio causes "the worm" in the fruit of plums, peaches, and sometimes apples. At Petal-Fall (5 days after bloom), and again at Shuck Split (14 days after bloom), spray an organic insecticide. Petal-Fall is when 75% of the flower petals have fallen. Shuck split happens after the fruit has just barely formed and has just expanded enough to split its papery covering (the "shuck"). Repeat in 10 - 14 days for a total of 3 sprays. Spray Kaolin Clay or Spinosad. In addition, place sheets under tree and in early morning and jar the tree with a padded mallet to cause curculios to drop to ground. Avoid harming young trees with this method.
Consider purchasing a live Christmas tree for the holidays. Afghan (Eldarica), Aleppo, and Italian Stone pines can often be found this time of year. A trick for watering these trees indoors is to place ice cubes on top of the soil, making sure there is a sturdy saucer underneath the pot. Avoid keeping these trees indoors for any longer than two weeks. To allow the tree to adjust to the abrupt change in lighting when moving outside, place the tree in shade first for about a week, then move gradually to more and more sun. Finally, plant your tree outside in a sunny area with very good drainage. Pamper it when planting by using bone meal or rock phosphate in the hole, and by following the regular watering with some seaweed solution for the first few months.
Choose and prepare areas for planting fruit trees in January. Many fruit trees, berries, and grapes become available in bare root form in January. Most fruit trees require a partner to pollinate. Therefore, choose a full sun area with plenty of space for two trees, for each type of fruit you wish to plant. Most fruiting plants prefer a well-drained, fertile, slightly acidic soil to a depth of 24 inches. If there are drainage problems or shallow soil, construct a raised bed with good garden soil. Work in some of the garden soil to the existing soil as much as possible before adding the rest on top. If you already have a deep soil, work in to the top six to twelve inches some high quality manure compost. Include soil sulfur and some cedar flakes to help lower the pH. Other amendments which can be dug in at the same time are Volcanite or greensand and a light application of organic fertilizer such as Rabbit Hill Farm's "Buds and Blooms."
Clean and oil gardening tools and equipment. Sharpen and repair, as necessary.