Overwinter Geraniums the Correct Way
As the end of the growing season appears it may be sad to think of your beautiful geraniums’ endless show of color coming to an end. Fear not! While non-hardy geraniums are considered annuals, overwintering your prized plant indoors can carry them through to the following year, giving you a jump start on spring and saving you some money if you usually replace them each year. But beware – it’s not quite as simple as carrying your geranium pot inside and waiting for spring. This article talks about two ways to overwinter geraniums in a way that will maximize your chance of success.
By Kristina Valle, Master Gardener
It’s never too early to start thinking about final garden projects as we near the end of our growing season. Sad to think of your beautiful geraniums’ endless show of color coming to an end? Fear not! While non-hardy geraniums are considered annuals, overwintering your prized plant indoors can carry them through to the following year, giving you a jump start on spring and saving you some money if you usually replace them each year. But beware – it’s not quite as simple as carrying your geranium pot inside and waiting for spring. This article talks about two ways to overwinter geraniums in a way that will maximize your chance of success.
Overwintered geraniums are an early memory of mine. I distinctly remember running down the basement stairs of my grandparent’s home and being struck with the scent of the potted geraniums, lined up across the west facing window; the vibrant colors, a welcome contrast to the bright white winter landscape outside.
There are two main ways to overwinter your geraniums, both of which need to be done before the first frost:
While my grandparents chose to keep tending to their geraniums through the winter months in their original pots, you might keep your geraniums in planters or heavy pots that would be impossible to move indoors. If you want to keep the plants potted, you can transplant them into smaller indoor pots by carefully digging up the root ball, and replanting into the pot of your choice. Before bringing the plant indoors, check for any pests trying to hitch a ride and remove any dead leaves. Now is also a good time to trim back any dead stems. Place your potted plant in front of a bright window or under florescent lights, and water every 1-2 weeks once the top of the soil dries out.
The enemy of the bare rooted geranium is moisture. That said, you have two options when you are ready to pull your geraniums in for the winter: 1) you can wait for the soil to dry out before digging up the root ball, or 2) you can dig the root ball out of the soil, tapping off any remaining dirt and then let your plant sit out for a day or so to ensure that all excess moisture has evaporated. As with your potted geranium option, be sure to inspect your plant for any pests and cut away any dead leaves, buds or flowers. The objective for this overwintering method is to encourage the plant into dormancy and not spend any energy into supporting existing or new growth.
You also have a few housing options for your plant: 1) paper bag (think landscape or grocery), 2) cardboard box or 3) tied up at the root to hang upside down. Each of these options ensures good ventilation which is critical to help ward off excess moisture and darkness, which will lull the plant into dormancy. Place your bag or box in a cool dry location such as a basement, root cellar or shed – anywhere where temperatures will remain around 55-65 degrees. Check on your plant about once a month to inspect for mold or other disease and manage as needed.
Getting Ready for Spring – Breaking Dormancy
About 6-8 weeks before the last frost day, inspect your plants and trim them back by one-half to two-thirds. Don’t be alarmed if your plant has lost many or all of its leaves. Plant the geranium in a pot, give it a good watering and set it in front of a bright window. Patience and care should generate the first signs of growth in the coming days and weeks and by time the risk of frost has passed, you’ll be weeks ahead of any store-bought geraniums available to gardeners.
Photo credit: University of Minnesota Extension (1)