Overwintering guide
How to overwinter square-stemmed pelargonium
Winter watering
Water only occasionally — enough that the rootball never dries out completely, no more. No feeding until spring growth begins.
The mistake that kills square-stemmed pelargonium in winter
Bringing square-stemmed pelargonium into a warm living room. Too much winter warmth forces weak, pale growth that collapses when it goes back outside — cool and bright beats warm and dim.
More square-stemmed pelargonium care
Overwintering square-stemmed pelargonium — FAQ
Does square-stemmed pelargonium need to come indoors for winter?
Square-stemmed Pelargonium is hardy to roughly USDA zone 9 — winter lows around -7°C. That means it takes cool conditions but not a real freeze. Square-stemmed Pelargonium will take cool conditions but not a hard freeze, so the aim is a frost-free winter rather than a warm one. An unheated greenhouse, porch, conservatory or bright garage all work well. Keep it cool, bright and on the dry side, and it will hold steady until growth restarts in spring.
When should I move square-stemmed pelargonium for winter?
Move under cover before the first hard frost; back outside after the last spring frost.
How often should I water square-stemmed pelargonium in winter?
Water only occasionally — enough that the rootball never dries out completely, no more. No feeding until spring growth begins.
What kills square-stemmed pelargonium over winter?
Bringing square-stemmed pelargonium into a warm living room. Too much winter warmth forces weak, pale growth that collapses when it goes back outside — cool and bright beats warm and dim.