Winter Solstice! December brings early winter on the 21st. There are always chores to be done in the garden for the all-year vegetable gardener.
Cool-season crops planted early in autumn will come to harvest in the next several weeks.
I was reading somewhere, probably in the farmer’s almanac, that winter holly berries predict the winter to come. More berries equal heavy winter, versus fewer berries making for a dry winter.
Remember to ventilate your cold frames or plastic tunnel on warm days for the gardeners growing through the winter. Check windbreaks, mulches, and winter protection; be prepared for winter storms. Spread straw, chopped leaves, or other mulch across the garden when the ground is frozen.
If your crops have slowed down during this time, don’t worry. It’s good to remember when daylight drops to less than 10 hours, cool-weather vegetables slip into a no-growth mode. Be assured that growth will resume when the daylight increases in January and February.
Be patient; crops grow slowly during short winter days, and don’t expect new growth until mid-January.
If temperatures are in the high 20s or low 30sF, cabbage, chard, head lettuce and carrots, turnips, and Brussels sprouts can be harvested this month–even from under a blanket of snow. Oh My.
Scallions and fall leeks can also be harvested; the leeks will be about the size of scallions. Onions can stay in the garden under a protective layer of mulch.
If snow has fallen on your winter vegetable garden, remember snow acts as an insulating blanket, and the cool-season vegetables beneath can still be harvested.
A killing frost or freeze will do the most damage to your vegetable garden in winter.
December Harvest Tips
- Asparagus: Asparagus is at least a 2–3-year commitment. Harvest when spears are about 8 inches tall when they can be snapped off at soil level. Don’t harvest spears smaller around than your little finger; let the roots continue to mature and store energy. Patients are required but is worth it.
- Broccoli: Keep an eye on broccoli florets as they develop. You’ll want to harvest them when they are full before they become heavy and floppy. Once the central floret is cut, smaller florets will develop in leaf axils for further harvest. Depending on the variety you are growing.
- Cabbage: Cabbage heads can withstand temperatures down to 20°F (-6°C). Headed cabbage can be cut from the base of the plant when it feels firm. If the head feels loose or flimsy, let it mature longer. If you cut the head and leave some of the stalk behind, smaller heads will form for the second harvest in mild-winter regions.
- Carrots and Root Crops: Dig and harvest root crops stored in the garden under mulch as needed. If the ground does not freeze, sunchokes, carrots, parsnips, rutabaga, turnips, and other root crops can spend winter underground.
- Chard: Chard leaves can be cut when about 6 inches long and still young. Please don’t bother with older leaves; send them to the compost pile. Cut just what you can eat and come back later for more. Chard will keep producing as long as you avoid lifting the roots.
- Lettuce: Lettuce must be protected from freezing temperatures; keep the plastic tunnel handy when temperatures dip. Leaf lettuce can be harvested, cut-and-come-again, just like chard. Cut the leaves you can eat just above the base and let the plant grow on. Head lettuce is ready for harvest when the head is firm. Keep excessive rain from the head lettuce, or it will swell up, and the head will split.
- Peas: Pick snow pears before pods begin to bulge; pick snap peas before pods fully develop; pick shelling peas when the pods are plump and still bright green–and tender. Begin the pea harvest soon after the first blossoms appear–the first pods for picking will be low on the plant. Continue to pick peas every day until the harvest is finished.
December Garden Maintenance
General garden clean-up
If you haven’t already cleaned up parts of the garden that are not being used, Now is a great time.
Place compost and leaf mulch on the vacant garden beds.
Check the garden before and after storms and add more mulch if necessary after storms, remove broken branches from orchard trees and check the weight of snow still on branches.
PRO TIP: Protect crops from freezing temperatures with mulch, plastic tunnels, or cold frames. Loose straw or fallen leaves will protect plants from freezing temperatures also.
Ensure tools have been cleansed, sharpened, and stored in a dry place. Coat the metal part of the tools with light oil to prevent rust. You will thank yourself in the Spring!
PRO TIP: Tool handles can be painted or taped with a bright color to make them easier to find.
Compost
Turn the compost pile with a fork and water to speed winter disintegration.
Don’t have compost? Learn how to Vermicompost here or check out my teaching schedule for upcoming classes in Spring.
Winter Cold Frame Tune-up
Ventilate cold frame on mild and warm days. Remember, lack of air movement can encourage diseases. Gradually give plants less water to better tolerate low temperatures; disease will also be less of a problem.
Check plants regularly to pick off dead or dying leaves before they rot.
Now, onion seed, cabbage, cauliflower, broccoli, leaf lettuce, mustard, radish, and spinach can be sown in the cold frame.
Where temperatures are frigid, a piece of plastic sheeting can be stretched over single-layer lids made of glass, plastic, or Plexiglas. Double layers of glass–or an added layer of plastic sheeting–will provide the most excellent insulation.
We wish you and your family a Very Merry Holiday season.
