Ask a Master Gardener: Will geraniums live through winter?
Q: I brought my geraniums inside before it got cold. Now what should I do with them? Will they live through the winter?
A: Geraniums can be overwintered in several ways. If you have brought in pots, or dug up and potted plants from the garden, set them in a cool location with lots of bright direct sunlight. Cut the plants back by half their original size and water well. From then on, only water as needed. They are nearly dormant over the winter and prefer to stay relatively dry. Don't fertilize until May just before placing them outside again.
Cuttings from trimming the plants can be rooted. Do this by removing 3- to 4-inch sections of the stem tip with a sharp knife. Pinch off the leaves from the lower half of the cutting. You may have better success if you dip the cut end into a rooting hormone, but you can skip this step. Place ends in a moist, porous, well-drained rooting medium such as perlite or vermiculite. Use small pots with good drainage. Several stems can be potted together. Keep moist and in indirect light. After six to eight weeks cuttings should have rooted and can be placed in pots of well-drained potting soil and moved to brighter light.
One other way of holding over geraniums is to place them into a deeper dormancy. You may lose more plants with this method, but depending on your space, it may be your best option. Geraniums are one of a few plants that can survive without soil for a time. When you dig them up, carefully remove most of the soil from their roots. Cut their stems back by about one-third. Then, hang them upside down or put them in open paper sacks, and store them, preferably in a dark, cool space. Temps ideally should run 45 to 50 degrees. During this dormancy, every month or two, put their roots in water for one to two hours. In March or April, trim off dead material, repot, water and put in a sunny location. Since they have been dormant, it may take a few weeks to see them re-awakened to new growth.
However you overwinter your geraniums, they will lose their outdoor hardiness from being inside for months, so when you're ready to take them back outside, they'll need to be gradually reintroduced to sun and wind. Put them in a shaded, protected area at first, and give them a little more time outside each day for a week or so. Eventually they'll toughen up and be happy in full sun again.
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