Timely Tips

What to Do in December 2025
Weekly Gardening Timely Tips from
Cornell Cooperative Extension of Westchester County

Dec. 7 to 13

Perennials: Seed heads of black-eyed Susan, coneflowers and native grasses and many native plants provide welcome meals for finches and other songbirds.

Flowers: Holidaypoinsettia plants may last well past the holidays if exposed to bright light and cool night temperatures in the 50s or 60s. Water them well, allowing them to dry slightly between waterings without getting to the point of wilting. Protect them from drafts and direct heat sources.

Fruits and Vegetables: Check the veggie garden for surviving harvestable produce. Remove spent plants and add healthy remnants to a compost pile. Remove leaves, grass and weeds around the stems and trunks of shrubs and fruit trees to discourage damage by critters. Consider using collars constructed of hardware cloth to protect tree trunks over winter where animal pressure is high. The collars should extend at least several inches above possible snow depth and be placed a few inches into the ground. Make sure the collars are wide enough that they don’t touch the surface of the trunk.

Trees and Shrubs: In areas that may receive heavy snowfall, evergreen shrubs that are small enough to reach safely and at risk of splitting under heavy snow or ice can be loosely tied. Jute or another soft biodegradable twine should be tied loosely at the base of the shrub, then gradually and loosely wrapped in a spiral upward. The twine should be wrapped tightly enough to keep the stems in place without immobilizing them. Wrapping should stop about a quarter from the top of the plant, and the end of the twine should be tied to the end of a stem. To avoid damage, snow and ice should be allowed to melt naturally, and the twine should be removed before growth starts in spring. When planting new evergreen shrubs in the future, selecting or training the plants to a single main stem will help them shed snow naturally without breakage.

Lawns: As cold weather persists and grass growth has stopped, the mower should be put away. If this has not already been done, the deck and body should be thoroughly cleaned, and the blade sharpened. Electric equipment batteries that are not rated for extreme cold should be stored in a dry place at a temperature around 40 to 50°F (with an overall safe range of approximately 32 to 104°F). Proper storage will prolong battery life, reduce environmental impact, and save money. Gas-powered equipment should be winterized by changing the oil, lubricating parts, and either draining fuel or adding a gas stabilizer to fuel tanks.

Houseplants: Aphids, mealy bugs, scale, spider mites, thrips, and whiteflies are common pests that can damage houseplants. A small infestation may be removed by hand, but heavily infested plants are often best discarded. For guidance on treatment options, contact the local Cooperative Extension.

General: To enjoy watching birds, birdfeeders should be set out if they have not already been placed. Feeders should be kept filled and cleaned regularly to maintain bird health. All visible debris should be removed, feeders scrubbed, sanitized, and dried before refilling. For more information, seehttps://www.allaboutbirds.org/news/browse/topic/feeding-birds/bird-feeders-feeding-birds#
Birds also require a continuous source of fresh, clean water that does not freeze.

Here’s a great holiday gift for the gardener in your life:a subscription to the Home Garden Lecture Series through Cornell Cooperative Extension of Westchester. There is one webinar lecture per month from January through May, and a tour in May while space lasts. Advance registration is required. The whole webinar series is $45; individual webinars are $5 each. Check out the brochure at https://www.canva.com/design/DAG37gykNic/RGq-kIdH95APY6-bKoGQYw/view?utm_content=DAG37gykNic&utm_campaign=designshare&utm_medium=link2&utm_source=uniquelinks&utlId=hcc45ab7c29 For more information, please call CCE at 914-285-4640, 914-285-4620 or email westchester@cornell.edu

Last updated December 6, 2025