December Garden Calendar

Lawns

• Continue to mow as long as the grass is still actively growing.
• Spray or hand pull winter annual weeds
• If no seeding is taking place, apply pre-emergent herbicide to prevent winter annuals. Irrigation may be needed to activate the herbicide.
• Dormant seeding can start when temperatures drop below 40 °F.
• Remove large piles of leaves and debris, deeper than 3 inches, from lawn areas by bagging and removing, mulching them into the lawn, or moving them to an area off turfgrass.
• Do not leave large piles of leaves and debris (deeper than 3 inches) for an extended period, as it will kill the grass under it.
• Store unused fertilizers in a dry location and out of reach of children and pets.
• Store pesticides in a cool (not freezing) dry location, out of reach of children and pets.
• Review lawn service contracts.
• Water fall-planted grass as needed.
• Avoid extensive walking on frozen grass.

Vegetables and Fruits

• Store unused seeds in a cool, dry location or refrigerator.
• Check vegetables and fruit in storage for spoilage.
• Mulch strawberries for winter protection.
• Clean and oil garden hand tools for winter.
• Till the soil and add organic matter.
• Store unused garden chemicals in a cool, dry, and safe location protected from freezing.
• Update garden journal for success and failure.
• Start planning for next spring on cold winter nights.
• Soil test to determine fertility needs.

Flowers

• Mulch grafted roses by mounding soil 6 to 8 inches deep to protect the graft.
• Continue to plant spring flowering bulbs until the ground is frozen.
• Leave flower seed heads to feed winter birds.
• Leave hollow flower stalks for stem-nesting bees.
• Give plants or gift certificates as holiday gifts for gardening friends.
• Empty decorative pots and containers, store them inside.

Trees and Shrubs

• Keep heavy snowfall from limbs, lightly shaking to avoid damage.
• Avoid shoveling snow onto trees and shrubs.
• Protect the trunks of young trees with wraps or cages from rabbit and deer
• Protect the trunks of thin-barked trees from western sun with tree wraps.
• Prune damaged and dead branches throughout the winter months.
• Water newly planted trees and shrubs in winter to prevent dry soil conditions.
• Mulch roots of tender shrubs such as azaleas and rhododendrons.
• Mulch on tree roots should be pulled away from the trunk to prevent root girdling.
• Mulch on tree roots shouldn’t be deeper than 4 inches to prevent rodents from nesting in it.
• Prune branches of junipers, pines, hollies, and other plants for holiday decorations.
• Rake and remove any leaves that are diseased to reduce reinfection in the spring

Miscellaneous

• Start planning for next year by making notes and preparing orders.
• Turn compost pile to encourage winter breakdown.
• Make your Christmas list and add gardening supplies.
• Keep houseplants out of hot and cold drafts near vents and windows.
• Winter is a great time to soil test.

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Have questions? The Garden Hotline is staffed by trained EMG volunteers and Extension staff who will assist you with questions.

Phone: (913) 715-7050

Email: garden.help@jocogov.org