Don't let frost kill your favorite geraniums. Instead, use these simple tips to keep geraniums indoors during the winter, and get a head start on your spring garden.

You can successfully keep tender Pelargoniums (commonly known as geraniums) alive inside your home throughout the winter, and get a great head start on your garden next spring with mature plants. Geraniums are usually treated as annual plants throughout most gardening zones in the United States. The first hard frost kills geraniums left outdoors. However, there are two methods for keeping geranium plants alive indoors during the winter months.

Requirements for Overwintering Geraniums

Geraniums can live indoors during the winter if given the proper conditions. They need cool temperatures, preferably in the low 60s (F). Most basements are ideal locations for geraniums during the winter months. Just add a fluorescent light fixture or a plant light to provide enough light for your plants. A sunny window can suffice for their light requirements, but check to make sure the radiator isn't blasting heat at the plants; they'll only be more stressed by the dry heat so typical of many homes during the winter. Make sure that you place a tray or pan underneath the pots so that water doesn't hurt your window sills or plant tables by leaving unsightly marks or rings.

Bringing Plants Inside

Bring your plant inside when fall temperatures begin consistently dropping into the 50s (F) at night or when a frost is threatened. Choose only the healthiest geraniums from among your outdoor plants. Remember, you donít have to save every single plant unless you want to; you can take cuttings from your plants next spring and grow more geraniums if you'd like more of a certain color or type. Once you've found the best specimens to bring indoors, youíll need to prepare them for life inside the house during the winter. Dig the plants from their containers or from the garden soil. Use water from your garden hose to clean the leaves and stems, checking plants carefully for any lurking insects, cocoons or egg cases that might hitch a ride indoors on the plant. Use water to wash them of before replanting your geranium. Use a plastic pot with drainage holes that is slightly larger than the root ball of your geraniums. Make sure the pot is clean. If you need to clean it before planting your geraniums, dunk it into a solution of 10% household bleach to 90% cold water, letting the plastic pot sit in the solution for 10 minutes. Then remove it and rinse thoroughly to get all the bleach off. Bleach kills many microorganisms that can harm plants. Trim back the selected plants so that they are about half the size of the fully grown plants. Remove yellow leaves and trim back most of the flowers. Now your geraniums are ready for transplanting. Use rocks, pebbles or a clean, paper, basket-style coffee filter inserted into the bottom of the pot to allow drainage but retain soil. Next, place a thin layer of sterile potting soil into the container. Place the geranium into the container and fill in the rest of the pot with potting soil or house plant soil. Do not use garden soil. Just as the plant can carry bugs into your house, garden soil can, too. Sterile potting soil purchased from a garden center prevents unwanted insect guests from arriving with your geranium collection. Tamp the soil down with your fingers and water the plant well outside so that excess water runs out of the pot. Then bring the pot indoors to the location youíve chosen. Keep the plant cool in a brightly lit area and water when the soil is dry.

How to Take Geranium Cuttings

Another method for saving cherished geraniums for next spring is to take cuttings from the parent plants several weeks before the last frost. While youíre not technically overwintering the plants, youíre propagating them so that you'll have plenty of the same colors or types next spring. Using a clean, sterile pair of scissors, take cuttings from newly emerged stems. Use soft wood cuttings only. To sterilize scissors, dunk them into rubbing alcohol. Pour some rubbing alcohol onto a clean cloth and rub it over your scissors in between cuts to keep them sterile and prevent spreading diseases among your geraniums. After taking cuttings, fill small pots with sterile soil. Dip the cut end of the geranium stem into rooting hormone powder, and then insert it into the soil. Water well and cover the cutting and pot with a clear plastic bag. Check it every few days to make sure that neither mold nor algae is growing on the soil or plant, signs that itís too wet. If it does look too wet, leave the bag off for a few hours or a day to dry it out. Water it well if it gets dry. You'll know your cutting has successfully rooted if a new set of leaves emerges in about 6 to 8 weeks.

Dormant Storage for Geraniums

Lastly, some gardeners sweat by storing dormant geraniums. Geraniums can actually die back and rejuvenate in the spring time. Remove plants from containers and shake off the excess soil from the roots. The roots should be free from clots of dirt, but not completely clean. Hang the plants upside down, root-side up, in a cool location where the temperatures never go above 50 degrees F. The plants should go dormant. Once a month, they must be taken down, and the roots soaked in cool water for approximately an hour. Then the plants must be hung up again in the same position. This method is often troublesome for gardeners simply because it's difficult to remember the monthly watering, and plants can die during storage if they dry out too much. Saving plants or taking cuttings are easier methods for most gardeners, especially beginners. Whether you save the entire plant or a cutting, it's hard to part with your favorite geraniums when autumn comes knocking on the garden gate. Saving plants means you can welcome spring with your favorite geraniums without spending a fortune to buy new plants.