How to Overwinter Geraniums

It’s not difficult to master wintering geraniums, thanks to their tough-as-nails constitution. By storing these plants in a dormant state or treating these annuals as houseplants, you can get a jump on next spring’s garden season — and save a few dollars along the way.

What Types of Geraniums Can be Overwintered?

Choose geraniums that belong to the Pelargonium genus for overwintering. This includes zonal or cutting geraniums, as well as ivy, scented or seed geraniums. Although Regal or Martha Washington geraniums fall into this group, they don’t usually overwinter well. Treat these cool-season favorites as true annuals and compost them when their flowering season draws to a close.

Store Plants in an Unfinished Basement

A low-effort method for wintering geraniums involves storing plants in a dormant state. Zonal geraniums yield consistently successful results with this technique due to their hearty genetics. Other geranium types may or may not overwinter well as dormant plants. This is the way that many of our grandparents overwintered geraniums, in an era when basements often had dirt floors, stone walls and high humidity. Modern basements are frequently too dry and warm to use this method.

Prep the Geranium Roots

Prepare geraniums for dormancy by lifting plants from the soil. In cold regions, you can wait until a light frost zaps leaves. A frost also helps by knocking down insects that might be hiding among leaves. Definitely gather geraniums before a killing frost occurs. Knock most of the soil from the roots. You might want to cut plants back by one-third to one-half, but it’s not necessary.

Grow Gerauiums as Houseplants

Another method for wintering geraniums is growing them as houseplants. You might want to cut plants back by one-third to one-half, depending on how much room you have indoors. Provide bright light, cool air temperatures and water only when the soil is dry. Check plants carefully before bringing them indoors to make sure you’re not ferrying insects inside.

Wintering geraniums causes plants to produce larger flowers as plants mature in years. This is especially true for zonal geraniums. Plants that are just a few years old can produce flower heads the size of softballs. Keeping geraniums over winter also saves money — money that you can spend on other plants for your garden.