Many gardeners like to keep geraniums from one year to the next. This provides plants for the home in the winter and eliminates the cost of buying new plants in the spring. Geraniums which are kept over from year to year also seem to be larger and bushier that those that are purchased in the spring. There are several methods of handling geraniums over the winter.
One method is to take cuttings and root them early in fall. Geranium stem cuttings, often called "slips," should be about four inches long. Take the slips from the tips of the healthiest stems. Remove the leaves on the bottom two inches of the cuttings. Cuttings will root faster if you dip the ends in a rooting hormone powder. Good potting mixtures are coarse sand, perlite, vermiculite or sphagnum peat moss. Plant the cuttings two inches deep in the potting mixture and water thoroughly. Place them in a north or east window or underneath artificial light until rooted. This generally takes three to four weeks.
After the cuttings have rooted, plant them in individual pots and put them in a well-lighted spot. Keep them evenly moist and fertilize lightly every four to six weeks once new growth appears.
Rather than take cuttings some people prefer to pot their best plants and bring them indoors for winter. Cut the plant back to about one-third its original height so the root system does not have to support so much foliage. It would die back anyway when the root system is cut and there is a change in light source. Carefully dig up the plant and pot it into a six-inch or larger flowerpot. Water thoroughly and put it by a sunny window.
If you have a place in your home, garage, or a shed which stays at 32 to 40 degrees, you can take containers of geraniums in for the winter and they will stay until spring. You may need to give them a little water about mid-winter, but they usually stay green and remain in a dormant state. In the spring when it warms up, cut them back and water them thoroughly, and they take right off for the year. Do not put outside until frost danger is passed. Remember, geraniums are heat loving plants. Cool temperatures in the spring have a tendency to stunt the plant, and it will take a long time for it to recover.
An old method of carrying geraniums over winter is to dig the plants, shake excess soil from their roots, then hang them in your basement. Most basements are too warm and dry for this method, but some people report success with this method. To find out if this will work in your basement, try it with several plants, but be sure to take cuttings too, in case you lose the original plant. Take the plants down occasionally and place the roots in water for several hours. Then, hang them back up. Do this several times over the winter to prevent them from drying out completely. Pot your geraniums in early spring, and put them in a sunny window until frost danger has passed.
Something to consider before pruning
Late summer and fall pruning can be done; however, keep in mind that any new growth which may be spurred by pruning at this time will not have time to harden off before winter. The tree will also have less time to heal up or seal that pruning cut as the tree is going dormant for the winter. The dry winter winds and weather could cause more drying or damage to the freshly cut area than if the pruning was done at the end of the winter (February and March). Pruning done toward the end of the winter has the advantage of seeing the shape of the tree with no leaves hiding the branches. You are dealing only with wood. The tree is also getting ready for its spring growth which will quickly seal pruning cut. If you have a branch that hangs too low, mark it with a string so you will know that this needs to be pruned in February or March.
Kyle Schulz is a Wadena County Master Gardener from Sebeka, and the regular gardening columnist for the Wadena Pioneer Journal.