OSU Gardening Calendar

December

Maintenance and Clean Up

Spread wood ashes evenly on vegetable garden. Use no more than 1.5 lb/100 sq ft/year. Don't use if the soil pH is greater than 7.0 or if potassium levels are excessive.
Protect new landscape plants from wind. Use stakes, guy wires and/or windbreaks as needed.
Yard sanitation: Rake leaves, cut and remove withered stalks of perennial flowers, mulch flowerbeds, hoe or pull winter weeds.
Turn the compost pile and protect from heavy rains, if necessary.
During heavy rains, watch for drainage problems in the yard. Tilling, ditching, and French drains are possible short-term solutions. Consider rain gardens and bioswales as a longer-term solution.
Check stored flower bulbs, fresh vegetables, fruits for rot and fungus problems. Discard any showing signs of rot.
Tie limbs of columnar evergreens to prevent snow or ice breakage.
Central/eastern Oregon: Water your plants every 6 to 8 weeks with a deep soaking to prevent drying out.
Western Oregon: Do not walk on lawns until frost has melted.
Western Oregon: Make sure that landscape plants in protected sites receive water regularly during the winter.

Planting/Propagation

Pest Monitoring and Management

Monitor landscape plants for problems. Don't treat unless a problem is identified.
Check for rodent damage around bases of trees and large shrubs. Remove weeds to prevent rodents from using them as hiding places. Use traps and approved baits as necessary.
Avoid mounding mulching materials around the bases of trees and shrubs. The mulch might provide cover for rodents.
Monitor spruce trees for spruce aphids. Treat if present in large numbers. Read and follow pesticide label directions.

Houseplants and Indoor Gardening

Protect poinsettias from cold, place in sunlight, don't let leaves touch cold windows; fertilize with houseplant fertilizer to maintain leaf color.
Monitor houseplants for adequate water and fertilizer. Water and fertilizer requirements generally are less in winter.

Download a PDF of the December Calendar for easy printing.

Updated September 10, 2009.

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