January Gardening Tips
Spend time in the garden in January? Absolutely! Apart from getting caught in a rainfall now and again (hopefully soon!) there are still lots of things you can do in your garden to start the new year off on the right foot. Winter-season chores will enhance your garden's health as spring approaches... everything you accomplish now will make spring that much sweeter and more beautiful.
Trees and shrubs
This month's tree and shrub tasks include planting, pruning and protecting. In San Diego County we can plant trees of all kinds: fruit trees, shade trees, and flowering trees. While you shouldn't prune flowering trees until after they've bloomed, you can now prune most shrubs and deciduous shade trees. Few birds are nesting in trees in the winter. This is an especially good time to prune coniferous trees like pines and cypress since their pests (various bark beetles) are not active at this time of the year. Keep up with raking - fallen leaves can do damage if left to smother the growth under them.
Deciduous Fruit Trees
December and January are the usual months to perform annual dormant pruning. Before making the first cut, check with a good, well-written reference on the particular technique for your specific variety. We carry an excellent book, “How to Prune Your Fruit Trees” at the nursery in the Gift Shop. Improper pruning seriously damages many fruit trees and each variety requires a different approach.
The first-half of this month should be your second application of dormant disease control. This may be either a Copper Sulfate or a Lime-sulfur product (do not use Lime-sulfur on Apricots). Applications of these products should be an annual chore to avoid infestations of such diseases as Peach Leaf Curl, Shothole Fungus, Apple Scab, Brown Rot and many others.
Many cool-season annuals can be planted this month. Some choices for sun include pansies, violas, Iceland poppies, stock, English daisy, linaria, flowering cabbage, flowering kale and the 'Bloomingdale' series of ranunculus. In shade try English, fairy or Chinese primrose, bedding cyclamen or cineraria. Keep deadheading (removing spent flowers) from annuals to help them continue blooming abundantly
This is the best month for your annual rose pruning. Apply a dormant disease and insect spray to the canes and immediate soil around the pruned roses. However, don't fertilize or water roses this month. They need to harden off for winter. In desert areas you may want to give them an occasional drink if you think they need it. Also, rake away any old mulch and add fresh. Immediately after pruning is the best time to do both of these chores.
Plant Azaleas and Camellias this month. They are best planted while in bloom which is helpful because you can see what colors you are adding to your garden. Azaleas are now forming buds at the tips of their branches. Feed them with a high phosphorus fertilizer from now until they are finished blooming, then switch to a standard "azalea" or "acid" fertilizer.
Sasanqua Camellia is in bloom right now. Although the flowers are smaller than and not as long-lasting as the camellia japonica, the plant blooms profusely and can take more sun.
Cymbidium Orchids: Some cymbidiums start to bloom in December although most bloom between February and March. Continue to feed the plants for bloom (low nitrogen fertilizer) until the buds open.
Native Plants: This is the growing season for California Natives so if the weather becomes extended-dry, water these plants. Native plants can also be pruned now, and they can absolutely still be planted.
Wildflowers: Sow wildflowers. A generous definition of "wildflower" is any annual or perennial that reseeds itself. Under this definition: cosmos, gaillardia, annual gypsophila, foxglove, larkspur, nasturtiums, violas and viper's bugloss (Echium vulgare). Their display can last into early summer.
Vegetables: There is still time to plant cool-season vegetables: arugula, broccoli, Brussels sprouts, cabbage, collards, endive, kale, kohlrabi, lettuce, mustard, peas and spinach. Start beets, carrots, parsnip, radish, rutabaga and turnips from seed only. Begin planting larger perennial vegetables like rhubarb, artichoke, horseradish and asparagus. Horseradish can be quite invasive so keep it in a container. Feed cool-season vegetables regularly and control weeds before they get out of hand. We have a great selection of winter vegetables at the nursery.
In areas where frosts are just an occasional thing, keep plantings well-watered so whenever a freeze threatens plants are more likely to survive. A well-hydrated plant is better-equipped to recover than a dehydrated plant. If a plant is damaged by frost resist the urge to prune the damaged parts. They may well protect the rest of the plant during any subsequent frost.
Move dish cacti and succulents and potted trees under cover for protection from cold and rain. For overnight protection when frost threatens, cover bougainvillea, fuchsia, hibiscus, and other sub-tropicals with large cardboard boxes or drape old sheets or tarps on stakes over them.
Cut back Butterfly Bush (Buddleja) hard this month. A rule of thumb is to cut it back about 75%. If you are trying to manage the plant in a small space, try cutting it back even more and then pinching the new growth every few weeks to create more branching.
Stimulate wisteria by cutting it back now. Cut back the long thin branches that appeared this season alongside or entangled with the older wood. Leave two or three buds at the base of the branch.
Plants for indoor color include: African violets, anthurium, azaleas, begonias, bromeliad, flowering cactus and kalanchoe, as well as the ever-dependable chrysanthemum. Be sure to give indoor plants bright, indirect light, keep them cool and out of drafts and water them just enough to keep the potting mix barely moist. Cacti and succulents are also good choices for the indoors but they will need direct sunlight and very little water.
Don't worry that your houseplants don't seem too vibrant right now--they're going dormant just like plants outdoors. Plants need this rest so stop feeding them and water them less frequently. Also, be sure they're not getting blasted with hot air from a heater vent or fireplace. Plants close to windows may get too much cold air at night so move them or provide a shield between them and the window. The most comfortable temperature range for indoor plants is 65-75 degrees. Remember, if you are comfortable chances are your plants are, too.
If you're too busy to give the garden much attention this month you're in luck as most plants will do quite well without requiring much. If you prepared for winter in the fall sit back and relax and enjoy the fresh start to the new year. If you still haven't finished your fall gardening tasks, don't worry, the fall planting window hasn't quite closed just yet.
Working in the garden this month is wonderful! The weather is cool and when the soil dries a little following a rain shower, it's perfect for digging. However, be careful not to go to work too quickly after a rain because working with wet soil can physically harm it. Grab a fistful and squeeze it lightly: If it crumbles when you loosen your grip it's just right. If it stays in a tight ball it's still too wet.