December is the start of deep winter in Maryland — the Chesapeake holds its great concentrations of Tundra Swans, geese, and ducks, Bald Eagles mass at Blackwater and Conowingo, the Christmas Bird Counts begin, and the cold, dry nights deliver the brilliant winter sky and the year's best meteor shower.
Week by week in December
December 3–9
- Bald Eagles mass at Blackwater and below Conowingo as the open farm country draws harriers, kestrels, and short-eared owls.
- Orion climbs the southeast and the Pleiades ride high in Taurus through the long, cold December nights.
- A planning week — order seeds and seed catalogs, review the past season, and force paperwhites indoors for winter bloom.
December 10–16
- The Geminid meteor shower peaks around December 14 — the year's richest, with bright meteors visible well before midnight from a dark site.
- The Christmas Bird Counts begin across Maryland, the great annual census of the wintering flocks.
- Storage crops, cold-sweetened greens, and the Chesapeake's prime winter oysters carry the holiday markets.
December 17–23
- The winter solstice near December 21 brings the longest night of the year — and the most time under the brilliant winter sky.
- Feeders are at their winter best with chickadees, titmice, cardinals, and juncos, while in irruption years pine siskins push south.
- American holly is bright with red berries for the holidays and the western mountains' Christmas-tree farms are at their busiest.
December 24–31
- Winter birding holds steady — Tundra Swans and diving ducks crowd the Chesapeake while Bald Eagles patrol the open water.
- The Winter Hexagon and brilliant Orion blaze through the long, frigid nights, closing the year under the clearest skies of the season.
- The bare sycamores, shaggy hickories, and dark loblolly pines stand against the gray sky as the woods settle into their winter rest.
Birds This Month
December is peak waterfowl winter on the Chesapeake. Blackwater National Wildlife Refuge holds thousands of Tundra Swans, Canada and snow geese, and rafts of canvasback, redhead, scaup, ruddy duck, bufflehead, and northern pintail, watched over by one of the densest concentrations of wintering and nesting Bald Eagles on the East Coast. Below the Conowingo Dam on the lower Susquehanna, eagles and gulls gather where the water stays open. The Christmas Bird Counts begin in mid-December, the great annual census.
The open farm country of the Eastern Shore and Piedmont draws hunting northern harriers, rough-legged and red-tailed hawks, American kestrels, and roosting short-eared owls at dusk. Feeders are at their winter best with Carolina chickadees, tufted titmice, white-throated sparrows, dark-eyed juncos, northern cardinals, and house and goldfinches; in irruption winters, pine siskins, purple finches, and the odd red-breasted nuthatch push south. The coastal bays hold wintering brant, black ducks, and loons.
What's Blooming
December offers no true wildflowers in Maryland's cold landscape, but the winter fields and marshes carry their own structure and color. The frost-killed meadows stand in tans and russets — the dark seed-heads of black-eyed Susan (the state flower) and coneflower, the splitting milkweed pods still trailing silk, the bleached Queen Anne's lace, and the tawny plumes of goldenrod, broomsedge, and the native grasses catching the low winter sun.
In the rich Piedmont woods, the evergreen ground plants hold their color through the cold — leathery Christmas fern, the paired red berries of partridgeberry, and the leaves of the cranefly orchid and rattlesnake plantain on the forest floor. The tidal marshes of the Chesapeake are wide sweeps of golden-brown cordgrass and switchgrass. The last native witch hazel may still hold a few yellow ribbon-flowers in sheltered woods, and in mild gardens the very earliest snowdrops can break ground during a December thaw. The standing seed-heads feed the wintering sparrows and finches.
Garden This Month
December settles the Maryland garden into its winter rest, but a few hardy crops and tasks remain. In the milder central and Eastern Shore zones, kale, collards, spinach, leeks, mâche, and Brussels sprouts keep cropping under row cover and in cold frames, and mulched carrots, parsnips, and leeks can be dug from the ground all winter. Check that mulch still protects the fall-planted garlic, the strawberries, and tender shrubs, and keep brushing heavy, wet snow off evergreens, boxwood, and hollies to prevent breakage.
Most of the month is for planning and protecting. Let snow accumulate over perennial beds as insulation, drain anything that could freeze and crack, and watch for deer browsing on bark and buds during lean weeks. On mild, dry days, prune dormant fruit trees and shade trees. Order seeds and seed catalogs, review the past season, and sketch next year's plan and rotations. Set up a grow-light shelf for the slowest seedlings — onions, leeks, and celery — to start in the new year, and force a few paperwhites or amaryllis indoors for winter bloom.
Zone 6b (western Maryland & the Frederick uplands): the garden is locked in cold. Let snow blanket the perennial beds as insulation, brush heavy wet snow off arborvitae and hollies, check mulch over garlic and carrots, and turn to seed catalogs and planning.
Zone 7a (central Piedmont & the Baltimore–Washington corridor): mostly dormant. Cold frames and low tunnels still hold hardy greens and spinach, mulched root crops keep in the ground, and mild days are good for dormant pruning and tool maintenance.
Zone 7b (lower Eastern Shore & the Bay's warming edge): the mildest gardens carry on. Kale, collards, spinach, and mâche keep cropping under row cover and in cold frames, fall-planted garlic sits under mulch, and you can plan and prune on the frequent mild days.
What's at the Farmers Market
December markets in Maryland run on winter stores and the holiday table. The storage crops carry the season — winter squash, sweet potatoes, potatoes, onions, garlic, carrots, beets, turnips, parsnips, and cabbage — joined by the cold-sweetened greens: kale, collards, spinach, Brussels sprouts, and leeks. Crisp storage apples and fresh cider from the western Maryland and Frederick orchards remain in good supply at the indoor and year-round markets.
The Chesapeake's oysters are at their cold-weather best, the heritage shellfish of the Bay in their prime winter months. Local honey, farmstead cheeses, eggs, baked goods, and holiday greens and wreaths fill out the stalls. Choose storage apples and squash that are firm and heavy with no soft spots, keep root vegetables cold and humid in the crisper, and store sweet potatoes and onions in a cool, dry, dark place rather than the refrigerator. Pick greens with deep color and crisp stems, and use the cold-sweetened brassicas while they are at their best.
Night Sky This Month
December's long, cold, dry nights bring back the brilliant winter sky and the year's best meteor shower over Maryland. The Geminid meteor shower peaks around December 14, the richest and most reliable of the year, sending dozens of bright, often colorful meteors an hour from Gemini — and because they fly well before midnight, they are easy to watch from a dark site like Assateague Island or the Garrett County highlands without staying up to dawn.
The winter constellations dominate the season. Orion climbs the southeast, his belt pointing down to dazzling Sirius, the Pleiades and Hyades ride high in Taurus, and the great Winter Hexagon sprawls across the sky, with the Orion Nebula glowing in binoculars. The winter solstice near the 21st brings the longest night of the year — and the most time under the stars. The printable Maryland night-sky guide lists this year's exact Geminid peak date, planet positions, and the best dark-sky sites near you.
Butterflies & Pollinators
December halts Maryland's butterfly flight, but the insects are present all around, hidden and dormant through the winter. The overwintering adults — mourning cloak, eastern comma, and question mark — are tucked behind loose bark, in woodpiles, hollow trees, and unheated sheds along the Piedmont and Coastal Plain woods, where they can survive the cold in a frozen, dormant state and will emerge on the first warm days of late winter, often Maryland's earliest butterflies of the new year.
The rest of the fauna waits out the cold in earlier stages. Monarchs have completed their journey to the Mexican overwintering forests, leaving none behind. The great spangled fritillary sleeps as a tiny unfed caterpillar in the leaf litter, the zebra and eastern tiger swallowtails as chrysalises camouflaged against twigs near their host pawpaw and cherry, and many skippers and whites as eggs or larvae in the dormant grasses. The undisturbed leaf litter, brush piles, and standing stems of the winter garden are full of next summer's butterflies — the best reason of all to leave the fall cleanup undone.
What to plant for them is in the Maryland native plants guide
Trees This Month
December reveals the full architecture of Maryland's forests, every deciduous tree stripped to bare branches against the winter sky. This is the month to read bark and form — the blocky bark of the mature white oak (the state tree), the shaggy strips of shagbark hickory, the pale smooth gray of American beech still holding its bleached marcescent leaves, and the flaking white sycamores glowing along the Potomac and Patuxent bottoms.
The evergreens carry the winter green and define the landscape. On the Eastern Shore and Coastal Plain, the loblolly pine dominates, glossy American holly is bright with red berries for the holidays, and eastern red cedar stands dark in the old fields; the baldcypress in the swamps is bare to its knees. In the cold western mountains of Garrett County, native eastern hemlock and planted red spruce hold the high country, and Maryland's Christmas-tree farms are at their busiest. The buds are already set and waiting — the fat clusters at the twig tips of the oaks and the long pointed buds of beech promise the spring to come.
The Maryland native plants guide covers what grows with them
Weather & Daylight
Across Maryland, a typical December day averages a high near 47°F and a low near 29°F, with about 3.7 inches of precipitation — statewide averages from the 1991–2020 U.S. climate normals.
Short, cold days hover in the upper 40s while long nights drop near freezing, damp chill settling over everything.
| Average high | 47°F |
|---|---|
| Average low | 29°F |
| Precipitation | 3.7 in |
| Sunrise (mid-month) | 7:19 ET |
| Sunset (mid-month) | 16:46 ET |
Figures are statewide averages over the 1991–2020 U.S. climate normals; local conditions vary with elevation and distance from the coast. Sunrise and sunset are computed for a midstate point on the 15th (ET).
Next month's version of this page, by email
One short note when Maryland's next month turns — what's arriving, blooming, and worth a night outside.
Go deeper with the Maryland guides
The complete Maryland birding, native-plant, and night-sky references — or the whole year, week by week, in one book.
Same month elsewhere: December in Massachusetts · December in Michigan · December in Minnesota