Mountain Garden December Checklist

Decorating

Living Christmas Tree

Norfolk Island pine (Araucaria heterophylla) makes a great small tree. Hide the pot in a cachepot; decorate with white lights, lightweight ornaments, garlands. Keep in cool, bright room; mist daily; water when soil barely moist; rotate for even light. Watch for scale, mealybugs, spider mites—treat with insecticidal soap.

Poinsettia Safety

Cats may nibble and get nauseated. Display out of reach or choose alternatives: azaleas, bromeliads, Christmas cactus, freesia, gardenia, miniature roses, orchids, rex begonia, star jasmine.

Outdoor Containers

Pot evergreens in frost-proof foam containers; place in sheltered spot (porch). Add creeping mahonia, English ivy, hardy herbs; decorate with bows/lights. Water when dry. Below 0°F: move to garage or wrap in frost blanket. Long-term container candidates: boxwood, dwarf Alberta spruce, dwarf Colorado spruce, topiaried junipers, meserveae holly, small pines ('Vanderwolf's Pyramid' limber pine).

Rosemary Topiary

Set in attractive container; add ribbon garland spiraling down; decorate with balls, dried flowers, pinecones. Bright room; water when soil barely dry. Move outside after frost danger passes.

Planning

Assess Winter Structure

Note where evergreens and ornamental grasses would enhance winter landscape. For xeriscapes: hardy agaves, cylindrical opuntias, yuccas. Mark spots with stakes for spring planting.

Planting

Hyacinths

Prechilled bulbs (available until early December) bloom in weeks. Gift idea: plant single bulb in hourglass vase with pebbles/marbles; water to bulb base; tie ribbon.

Maintenance

Cover Marginally Hardy Shrubs

Before temps drop below 0°F, cover with evergreen boughs, pine needles, or frost blankets (pinned). Plants to protect: autumn sage, Eumorphia prostrata, hardy rosemary 'Arp', lavender, lavender cotton, Penstemon fruticosus, P. rupicola, stonecress, thymes, winter savory.

Prune Evergreens

Partially dormant now—good time to remove limbs, thin twiggy growth, shorten overlong branches. Cut just beyond side branches; prune evenly. Save trimmings for mulch or holiday decor (soak in water, keep cool, spray with antidesiccant).

Spread Winter Mulch

3–4 inches of lightweight mulch (hay, leaves, straw, pine needles) over entire garden keeps ground frozen, prevents freeze-thaw cycles. Cover perennial crowns; keep 12+ inches from tree trunks to deter rodents. Remove in spring to warm soil.

Support Wildlife

Brush pile for winter cover. Avoid disturbing hibernating toads. Multiple feeder types: suet (chickadees, jays, woodpeckers), thistle (finches, juncos), sunflower (cardinals, chickadees). Heated water source or de-icer in birdbath. Keep clean.

Christmas Cactus Care

Blooming: bright indirect light, even moisture, fertilize every 7–10 days. Post-bloom: rest 6–8 weeks in cool, dim room, no artificial night light, water sparingly. Then return to bright light, increase water—reblooms in weeks.

Prevent Winter Dehydration

Spray antitranspirant (e.g., Wilt-Pruf) on arborvitae, azalea, boxwood, dwarf conifers, false cypress, holly. One application lasts months.