Delaware Nature Guide: December 2026
December settles Delaware into winter — short days, the first lasting cold, and the bay-shore refuges holding their full masses of Snow Geese and ducks. The Christmas Bird Counts tally the wintering flocks, the long dark nights offer the year's finest stargazing, and the evergreen hollies define a bare, quiet landscape.
What to look for this week
- Tens of thousands of snow geese crowd the Bombay Hook impoundments, rising in roaring white clouds — the heart of Delaware's winter waterfowl spectacle.
- The Quadrantid meteor shower peaks in a short, sharp burst around January 3; watch the northeast after midnight from a dark Cape Henlopen or lower-Sussex site.
- A kitchen-table planning week — order seeds and sketch beds, leaving any snow banked over perennials as insulation against the coastal-plain freeze-thaw.
- American holly, the state tree, stands glossy and red-berried through the bare coastal-plain woods, the signature green of the Delaware winter.
Birds This Month
December is deep into Delaware's winter waterfowl season. Bombay Hook and Prime Hook hold their full wintering spectacle — tens of thousands of snow geese, big flocks of tundra swans and Canada geese, and the assembled ducks: northern pintail, American wigeon, green-winged teal, gadwall, northern shoveler, black ducks, and mallards. Bald eagles, northern harriers, and short-eared owls hunt the marsh, and the long-running Christmas Bird Counts tally the winter birds across the state this month.
On the coast at Cape Henlopen and the Indian River Inlet, the sea ducks are in: long-tailed ducks, surf and black scoters, buffleheads, red-throated and common loons, horned grebes, and gannets offshore, with purple sandpipers on the jetties. At feeders, the resident Carolina chickadees, titmice, white-breasted nuthatches, cardinals, and Carolina wrens are joined by wintering juncos and white-throated sparrows.
This month's tip: join or follow a local Christmas Bird Count — Delaware's counts are among the most productive in the region thanks to the bay-shore refuges, and they are a fine way to see the full winter avifauna with experienced birders.
What's Blooming
Nothing blooms outdoors in a Delaware December — the ground is freezing and the flowering year has closed. What the dormant season offers is held color and structure across a bare, water-laced landscape. The scarlet berries of winterberry holly burn in the bay-shore swamps now that the leaves have dropped, and the glossy red-and-green of American holly, the state tree, abundant through the coastal-plain woods, becomes the signature sight of the Delaware winter — and the traditional holiday green.
The crimson stems of red-osier dogwood brighten the wet ditches, the dark blue-green of eastern red cedar studs the old fields, and the tawny, rattling seed heads of switchgrass, little bluestem, and the marsh cordgrasses stand through the frost in the fields and tidal marshes of Bombay Hook and Prime Hook. Indoors, this is the season of amaryllis, forced paperwhites, and poinsettias, and the start of the long catalog-dreaming weeks when Delaware gardeners begin planning the beds they cannot yet touch.
Garden This Month
December gardening in Delaware is mostly rest, protection, and planning. Beds are dormant statewide, and the active work is done — but a few cold-hardy greens like kale, spinach, and mache can still be harvested from under a low tunnel or cold frame, especially in the mild lower counties. Mulch the garlic bed and tender perennials if you have not, water any evergreens during dry spells before the ground freezes hard, and gently brush heavy, wet snow off boxwood, holly, and arborvitae to prevent branch breakage.
This is the start of the planning season: order seed catalogs, take stock of what worked, and begin sketching next year's beds and ordering the sweet corn, tomato, watermelon, and lima-bean varieties that suit the long First State growing season. Check stored dahlia tubers, potatoes, and bulbs for rot and adjust the storage if needed. On a mild, dry day late in the month you can begin dormant pruning of fruit trees and shrubs. Cut greens, holly, and pine boughs for the holidays, and enjoy the quiet pause before the cycle begins again. Leave the standing seed heads and leaf litter for the birds and overwintering insects.
Zone 7a (northern New Castle County): fully dormant now — leave snow banked over perennials as insulation against the freeze-thaw heaving that does the most damage here, and check stored bulbs and tubers for rot.
Zone 7b (Kent, Sussex, and the coast): the mildest corner of the state may still yield frost-hardy greens under a low tunnel — harvest kale, spinach, and mache through the month, and start browsing seed catalogs for the long season ahead.
What's at the Farmers Market
December markets in Delaware are firmly in the winter storage season, with a holiday lean. The durable harvest fills the stands: winter squash, pumpkins, sweet potatoes, white potatoes, onions, garlic, carrots, beets, turnips, parsnips, cabbage, and Brussels sprouts, alongside keeping apples eating crisp from cold storage. Heated hoop houses around Kent and Sussex supply frost-sweetened spinach, kale, and collards, and the markets carry holiday greens, wreaths, and cut American holly.
Look also for local honey, eggs, dried beans, jarred preserves, and cider held cold from the fall pressing. Store roots and squash cool and dark — sweet potatoes prefer a warmer, drier spot than other roots — and apples held cold and apart from other produce keep for weeks. Cabbage and Brussels sprouts hold well in the crisper, the sprouts at their sweetest after the frosts. Choose firm, heavy, unblemished produce that will keep through the cold months. The selection is narrow but durable, the table leaning on the harvest cured and stored through the fall.
Night Sky This Month
December gives Delaware its longest nights of the year around the winter solstice, and the cold, dry air makes for superb stargazing. The brilliant winter sky is in full command: Orion climbs the southeastern sky in the evening, his belt pointing down to Sirius, the brightest star in the night, and up to orange Aldebaran and the tiny dipper of the Pleiades in Taurus. The bright twins of Gemini and the great Winter Hexagon sprawl across the sky.
The Geminid meteor shower peaks around December 14, the richest and most reliable shower of the year, producing dozens of bright, often colorful meteors per hour from a dark site — the radiant near Gemini is up most of the night, making it the best meteor display Delaware offers. Bundle up and watch after dark. The Orion Nebula in the Hunter's sword is a fine telescope and binocular target on these clear, cold nights. Seek the darkest skies at Cape Henlopen and the lower Sussex coast.
Exact planet positions and this year's Geminid peak timing vary year to year — the printable Delaware night-sky guide carries the current dates and viewing details for your region.
Butterflies & Pollinators
No butterflies fly in a Delaware December — the cold has fully ended the season. The state's butterflies are scattered across the coastal plain in their hidden overwintering forms, waiting out the winter. The mourning cloaks, eastern commas, and question marks that overwinter as adults are tucked behind loose bark, in woodpiles, and inside hollow trees along the wooded stream corridors of White Clay Creek and the Brandywine, their natural antifreeze letting them survive hard freezes so they can fly on the first warm days of late winter.
The eastern tiger and spicebush swallowtails wait out the cold as chrysalides anchored to twigs in the moist coastal-plain woods, the great spangled fritillary survives as a tiny first-stage caterpillar in the leaf litter, and the monarchs that streamed down the Cape Henlopen coast in fall are now clustered in the oyamel firs of central Mexico. This is the season to leave brush piles, leaf litter, and standing stems undisturbed — they shelter the dormant butterflies — and to plan next year's garden around native milkweed, spicebush, and a long succession of nectar flowers for the First State's returning broods.
Trees This Month
December finds Delaware's trees fully bare and dormant, and the evergreens carrying the winter woods — never more so than this month, when the American holly, the state tree, stands at its glossy, red-berried best across the coastal plain and supplies the traditional holiday green. The dark loblolly pines of southern Sussex hold the canopy, the eastern red cedars stud the old fields, and the Atlantic white cedar darkens the frozen freshwater swamps.
The deciduous trees stand at their most readable: the young white oaks and American beech still hold tan, papery leaves through marcescence, the sweetgums dangle their spiky seed balls, the sycamores show mottled cream-and-gray bark along the Brandywine and Christina, and the broad upland silhouettes of white and willow oak and the straight columns of tulip tree read clearly against a gray or snowy sky. The bald cypress at Trap Pond stands leafless and rust-gray over the dark water, the northernmost stand of its kind. The First State woods are settled deep into their long winter rest.
Go deeper with the Delaware guides
The complete Delaware birding, native-plant, wildflower, and night-sky guides — or the whole year in one bundle.
Same month elsewhere: December in Washington, D.C. · December in Florida · December in Georgia