Cold damage
Dark, water-soaked leaves that turn black after frost or a cold draft.
What you'll see
- Leaves look water-soaked and dark green, then turn black or brown and collapse.
- Tropical houseplants chilled below about 50°F (10°C) drop leaves, wilt or get spots.
- Soft new shoots and tips are hit first, and damage can keep appearing for a week.
Why it happens
Freezing forms ice that bursts plant cells, and tropical plants can be hurt by cold even well above freezing.
How to fix it
- Move potted plants into steady warmth, above about 50°F (10°C), away from the cold.
- Water sparingly; cold, wet soil invites root rot while the plant recovers.
- Wait until frosts are over or new growth shows, then cut back to healthy buds.
Keep it from coming back
- Keep tropical plants away from drafts, cold windows and unheated porches.
- Cover outdoor plants overnight with fleece or an old sheet when frost is forecast, not plastic.
- Bring tender potted plants indoors before the first frost.
Read more
- Which window is best for plants?
- Moving houseplants outside and back in
- Winter care for houseplants
- Frost dates: when to plant
- Hardening off seedlings
Sources
- RHS: Frost damage
- Missouri Botanical Garden: Frost injury and ice damage
- University of Maryland Extension: Diagnose indoor plant problems
General guidance, not a diagnosis. For valuable, edible or outdoor crops, check with a local extension service or plant expert. Use any product exactly as its label says, and keep children and pets away while it dries.