Can My Plant Go Outside? Calculator
Check tonight’s low against your plant’s cold tolerance before moving it out.
Check the overnight low, not the daytime high, because cold damage happens after dark. Bring plants in before the first autumn cold snap.
Before you move plants outdoors
A summer holiday outdoors can do houseplants a world of good, but one cold night can undo it. This check compares the forecast overnight low with your plant's cold tolerance (plus a small safety margin) and tells you whether to leave it out or bring it in.
Two things to remember
- Acclimatise gradually to avoid sun-scorch on indoor-grown leaves.
- Watch the forecast and bring plants in well before nights turn cold in autumn.
Frequently Asked Questions
What temperature is too cold for houseplants?
Most tropical houseplants start to suffer below about 12-13°C (55°F) and can be seriously damaged below 10°C (50°F). Cold-sensitive plants like calatheas and many aroids may show damage even before that, so the calculator builds in a safety buffer.
Do I need to harden plants off before putting them outside?
Yes. Even when it’s warm enough, move plants out gradually. Start with an hour or two in shade and build up over 1-2 weeks. Sudden full sun will scorch leaves grown indoors, regardless of temperature.
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