Gardening tips for December | Jefferson City News Tribune

Gardening tips for houseplants, trees and shrubs in December.

Houseplants

In winter, houseplants generally need less water than in summer due to less sunlight. Be careful and use lukewarm water instead of cold water. Soil that is too moist can cause fungus gnats to lay more eggs in the moist soil.

When purchasing houseplants in winter, be sure to protect the foliage from the cold on the way home. Place the plants in a cardboard box or other protective cover to prevent damage to the leaves.

Move houseplants away from icy windows on extremely cold nights to prevent cold damage.

Poinsettias thrive best in bright, indirect light and night temperatures between 50 and 60 degrees. Keep plants away from drafts, registers and radiators. Allow the soil to dry slightly between thorough waterings. Make sure the water can drain and evaporate. If necessary, punch holes in the decorative film.

Check houseplants regularly for common pests such as aphids, spider mites, scale, mealybugs, whiteflies and thrips.

Trees and bushes

Only female hollies bear the red berries. A male tree must be nearby for pollination and fruit formation.

Branches of apples, pears and other rose plants that have been infected with fire blight can now be safely cut off. Another option is to wait until a dry spell in mid-summer.

Make sure the root area of ​​the shrubs is thoroughly mulched. Any organic material will do.

Living Christmas trees will keep their needles longer if you make a clean, fresh cut at the base and always leave the trunk in water.

Holly trees can now be trimmed. The cuttings can be used for Christmas decorations.

Miscellaneous

Monitor overwintering dormant plants, bulbs and tubers by ensuring they have not completely dried out or rotted.

Check whether seeds purchased for next season need stratification to germinate. The seed package should indicate whether this process is required. The most common seeds that require stratification include Asclepias, Echinacea, Rudbeckia and Baptisia. If necessary, replicate cold stratification by placing the seeds in the refrigerator at 33-40°C for 1-3 months.

Dhruba Dhakal, PhD, is a University of Missouri Extension Gardener who has served Missourians in central Missouri for about a decade. Dhakal can be contacted for gardening questions at (email protected).