Houseplant Care in December
December is maintenance mode. Don’t propagate, don’t repot, don’t fertilize. Just keep the survivors alive.
Minimum watering. No fertilizer. Daily pest checks during heating-system runtime. Keep humidity above 35% if possible.
Light in December
Lowest light of the year. Even snake plant and ZZ benefit from a grow bulb in pure-interior rooms.
Watering in December
Some species (especially cacti and succulents) need almost no water in December. Aroids need much less than they did in July. Finger-test before every watering.
Pests and problems to watch in December
Spider mites at peak. Fungus gnats if you over-water. Bacterial leaf spot if humidity-loving species sit in cold drafts.
What to plan now
Plan repot list for March. Wishlist any species you want to add next spring. Start reading up on light meters — January is the highest-leverage month to deploy one.