Knowledgebase
Wintering geraniums #211821
Asked September 10, 2014, 6:50 PM EDT
Jefferson County Colorado
Expert Response
There are two common ways to overwinter geraniums. The first way is to bring pots indoors or pot up those growing in a garden bed. Next place them in a bright window, water and cut back about 1/3 to 1/2 of their current growth. The temperatures should be 65 to 70 degrees F during the day and about 10 degrees cooler at night. Warmer temperatures cause the plants to become spindly. If you don't have a bright window, you can use grow lights and keep them on 12 hours a day. You'll want to water when the soil dries.
The other method involves taking the plants out of their pots (or digging them up, shaking off as much of the soil clinging to the roots as you can. They may then be placed in large brown paper bags or hung upside down in a dry location with temperatures in the 45-55 degrees F range. They can then be potted up in March, watered and placed in light as above. The plants can be set outside after the last frost in May.
If your garage temperatures drop below 45 degrees then that is not the location for overwintering them. Be aware too, that if you bring potted plants indoors for the winter, they can contain fungus gnats. These insects decompose organic matter in soil, but can become a nuisance indoors. You may want to consider using fresh soil for overwintering the plants.
Good luck!
Yes, they do not need to be watered all winter in this particular situation.
Good luck!