PLANT
Plant bareroot trees, shrubs, roses and vines.
If you still haven’t planted your tulip bulbs, there is still time.
If you’d like to grow your own blackberries or raspberries, plant canes now while they are dormant.
If you’re planning on indoor color this winter, it’s time to pot up those bulbs you’ve been chilling the last couple of months. Get them moved into a warm and cozy area of the house so they’ll be tricked into thinking spring has arrived.
Plant native hedges to encourage wildlife and create attractive boundaries around your garden.
Get blueberries in the ground this winter for an attractive addition to the fruit garden. With pretty white flowers, delicious berries and fiery autumn foliage, these acid-loving plants provide constant interest.
Plant more lettuce in your cold frame.
Strawberry plants should be installed now.
FERTILIZE
Get your soil tested and prepared for spring.
If weather is mild, feed pansies, snapdragons and other winter flowers.
Stop feeding your houseplants until February or March and then only lightly.
PRUNE
Remove limbs or branches damaged by storms, suckers and water sprouts, too.
Hollies may be trimmed now and the prunings used in holiday decorations.
If you haven’t already, cut down dead asparagus foliage and mulch the entire bed with straw.
Lightly and discreetly prune Southern magnolia, juniper, golden false cypress and hollies, and use the sprigs for inexpensive wreaths and swags.
Prune climbing roses now, cutting away diseased or damaged growth and tying any new shoots to their support. Prune older, flowered side shoots back by two-thirds of their length.
Prune grape vines.
Prune Japanese maples now if needed, as they will bleed sap if pruning is done any later.
Start pruning your wisteria by removing the longer canes.
WATER
As houseplants grow more slowly during winter, increase the time between waterings, but do not cut back on the amount of water. Over-watering is the biggest risk to houseplants in winter … go easy.
December can be surprisingly dry. Don’t forget to irrigate, even if it feels odd. Plants are especially vulnerable to drought and frost damage right now, and they need your help.
Insulate outdoor taps or turn them off at the mains and pack away unneeded hoses. Turn off and drain sprinkler systems by removing the head from the sprinkler at the lowest point of your lawn or install a sprinkler end drain.
Spot check any newly planted trees, shrubs and perennials for watering needs. If there’s been no rain for a week, you need to drag out the hose and water your plants. Remember, newly installed sod needs water, too!
Water greenhouse plants sparingly to maintain as dry an atmosphere as possible.
Water houseplants with tepid water. Cold water may shock them.
Wake up amaryllis bulbs by watering once, placing in a bright spot and waiting for them to respond. If no response in a couple of weeks, water again … but don’t repeatedly water an unresponsive bulb or it may rot.
For those with outdoor ponds, be sure to add water as needed to keep aquatic plants from drying out. Also make sure to break a hole when ice forms across the top of your pond to release accumulated gases and allow oxygen to enter.
Check overwintered plants in the basement and garage for possible water needs.
PEST CONTROL
Be on the lookout for any bagworm sacs in your garden and landscape. Handpick to remove as needed.
Clean up garden debris to eliminate overwintering areas for diseases and insect pests.
Gather up old mulch from around the base of rose bushes that suffered from blackspot or rust this summer to reduce the chance of infection next year. DON’T put in compost. Replace with fresh mulch.
If you haven’t already done so, clean out your greenhouse thoroughly. Wash the inner sheeting, the floor and benches with horticultural disinfectant to kill any overwintering pests and diseases.
In addition to keeping feeders full, hang suet cakes to attract birds that will eat pests in your garden.
Take precautions against browsing winter animals, including deer, rabbits, mice and voles. Deer fencing, trunk wrappings, mesh wire, scented oils, a good guard dog or a hungry barn cat are just a few options.
Apply broadleaf herbicides to control winter annual and perennial weeds. Use only as directed.
Don’t store firewood in the house as insects can come in with it. Leave the wood outside until you are ready to use it. Burn the oldest wood first so pest populations do not get a head start.
ODD JOBS
December is a good month for reflection and for going over your garden journal. What worked or didn’t work this year? Hopefully, you’ve been keeping up with information about what you planted, when and how it fared. Think ahead about plants that need to be moved – or removed – and consider what you might want to try next year.
All power equipment should be winterized before storage. Change the oil and lubricate moving parts. Either drain fuel systems or add a gas stabilizing additive to the tank. (You’ll be a step ahead next spring if you have your mower blades sharpened, too.)
Clean and oil all garden hand tools before storing for winter.
Avoid walking on your lawn when it is blanketed by heavy frost, as this will damage the grass beneath.
Be prepared for sudden swings in temperature and protect tender plants with row covers, newspaper or blankets.
Be sure newly purchased indoor plants are well protected for the trip home. Exposure to icy temperatures for even a few moments may cause injury.
Be sure the root zones of azaleas and rhododendrons are thoroughly mulched. Any organic material will do, but mulches made from oak leaves, shredded oak bark or pine needles are preferred.
Carefully plan your vegetable garden for next year so you ensure good crop rotation to avoid a buildup of pests and diseases.
Check on those stored summer tubers and bulbs.
Check that climbing plants are securely attached with plant ties to their supports.
Choose a dry day to clear out the garden shed in preparation for the spring. While you’re there, check it for security. This is particularly important in winter when you visit it less often.
Christmas trees hold needles longer if you make a clean, fresh cut at the base and always keep the trunk standing in water.
Clean leaves of large and smooth-leaved houseplants such as dracaena, philodendron, ficus, etc.
Continue to collect fallen leaves to be used as mulch and add to leaf bins or compost bins to rot down.
Cover compost bins with a piece of old carpet or some plastic sheeting to prevent the compost from becoming too cold and wet to rot down.
Cover strawberries with a floating row cover – they’ll fare better over winter and bear earlier next spring.
Frost action ruins clay pottery. Are your pots stored? Your birdbath bowl?
Give houseplants as much light as possible as days grow shorter.
Hairspray works well to keep seed heads and dried flowers intact on wreaths and arrangements.
Holiday poinsettia plants do best with sun for at least half the day and night temperatures in the 50s or 60s. Keep plants away from drafts, registers and radiators, and let the soil dry only slightly between thorough waterings. Be sure to punch holes in decorative foil wraps to prevent soggy soil conditions.
If the soil is dry enough, dig new beds, especially those to be used in February or March. Add plenty of organic matter while digging so only a light raking will be needed at planting time.
Inspect your stock of saved seeds to confirm they’re dry and secure.
Leave some of those dried perennial seed heads standing – they’ll help feed the songbirds. Coneflowers, black-eyed Susans and blackberry lilies are just a few great, natural seed sources for birds.
Leave the faded flower heads on your hydrangeas until the spring, as they will provide frost protection to the swelling buds farther down the stems.
Only female holly trees bear the colorful berries. There must be a male tree growing nearby for pollination if fruits are desired.
Overwintering geraniums like bright light and cool temperatures. Keep soils on the dry side.
Place a few plastic jugs filled with water between rows of cole plants to collect heat during the day and radiate it back at night.
Prepare your planting beds now with compost and manure for planting in early spring.
Provide houseplants with increased humidity; mist often or place plants over a tray of moist pebbles.
Give gardening tools and subscriptions to gardening magazines as gifts.
Take an inventory of tools and equipment you need for next year. Add them to your Christmas list!
Turn over empty beds and borders, and pile compost or partially composted leaves/manure on top – let the worms and frosts break up the clods of soil.
Wash and disinfect bird feeders and baths.
Wood ashes from the fireplace, used sparingly, are a good source of nutrients for the garden, especially phlox, sweet William, peony and spring-flowering bulbs. To use wood ashes for spring plantings, store them in an old metal tub or other dry and fireproof container. CAUTION: Make sure there are no live coals before storing wood ashes.
If you have any leftover seeds, store them in a cool and dry place. Some gardeners save their seeds in an airtight jar or plastic bag placed in the refrigerator or freezer.
After purchasing a living Christmas tree, leave it outside until a few days before Dec. 25 to keep the tree from becoming stressed. Remember to keep it watered.
Living plants that make good Christmas gifts include herbs. Basil, lavender, lemon balm, marjoram, mint, oregano, parsley, rosemary, tarragon and thyme grow well indoors in a sunny window.
Resist the urge to feed squirrels when you feed the birds. Squirrels are cute to watch, but they can be very damaging in a garden. After you stop feeding them, they’ll stay and will keep looking for food, digging up bedding plants and even potted plants looking for roots to chew or bulbs to eat.
Become a Master Gardener! Call your county Extension office for more details.