Northern California Coastal & Inland Valleys
Create a plan to protect delicate plants from frost. Move delicate cymbidium orchids, potted citrus, and other frost sensitive plants such as succulents and cactus under eaves or against a south-facing wall. Build lightweight wooden frames that can be covered with plastic or fabric to protect plants in the ground. Watch for cold days with no wind which usually indicate a frost is imminent.
Add a protective layer of compost or mulch around the roots of perennial plants and shrubs. Slightly dibble the mulch into the existing soil to incorporate nutrients into the soil around the roots. Even if the temperatures drop below freezing, the roots will be protected. Add a product such as Dr. Earth to stimulate enzymes and beneficial bacteria in the soil.
Ferns shine in the winter months. Make sure they are groomed and ready to take their place center stage. Remove dead, faded, or broken fronds. Fertilize with liquid fish to stimulate new growth.
Clean and Sharpen Pruning Tools
Next month is the beginning of dormant-season pruning so it's time to gather your pruning tools for cleaning and sharpening. Use a metal file to sharpen blades on shears and loppers. Clean wooden handles with linseed oil. A small round metal file can be used to sharpen saw blades or chain saw blades. Oil mechanical parts with WD-40 or other lubricating products. Remove rust with steel wool or bronze wool.
Stop Watering Cactus
Give potted cactus plants a winter break by holding back water between now and Mid-February. This included indoor-grown cactus. Succulents such as Christmas cactus (Schlumbergera spp.) should be allowed to go dry between waterings to give the plants a rest. Plants native to the tropics and the desert benefit from a few months' resting period.