As you watch your garden transition out of its summer showiness into the rich hues of autumn, it’s time to think about overwintering geraniums. You don’t have to lose your ornamental favorites to the first frost! It’s actually easy to save geraniums from a compost bin fate, so you can enjoy their annual flowers next year (and the year after and so on).

Geraniums are drought and heat tolerant, and still they produce abundant blossoms that attract pollinators throughout the season. It’s no wonder they’re the most popular flowering plants. Gardeners return to them time and again for hanging baskets, container gardens, and in-ground installations because it’s hard to beat the variety of colors and leaf shapes these tough yet gorgeous plants offer.

In this article, I’ll explain the process of overwintering geraniums, including preparing the plants, five overwintering methods, and how to bring them out of dormancy in the spring.

Perennial geraniums vs annual geraniums

To start, let’s clear up some common confusion about geraniums. There are two types of plants that we call geranium:

• Pelargonium spp. geraniums are tender perennial plants that we typically treat as annuals. They’re not “true” geraniums, but they do share the common name. These plants originated in South Africa, and there are about 280 species. This is usually what gardeners are talking about when they talk about geraniums, including zonal geraniums, seed geraniums, and pelargonium hybrids.
• Geranium spp. geraniums are perennials. These are also known as wild geraniums, hardy geraniums and cranesbills. Various perennial geraniums are native to USDA zones 4 to 8. You’ll find these alongside roads and wooded paths, as well as in native plant gardens. This is not the type of geranium covered in this article.

Reasons for overwintering geraniums

Learning how to overwinter geraniums makes a lot of sense. Here are some of the reasons you may want to consider putting in the effort:

• Why spend money on new geraniums each year when you can continue growing the ones you love for free?
• If you choose to overwinter your geraniums as houseplants, you get to enjoy their company throughout the year.
• If you’re taking geranium cuttings, it’s fun to share them with your plant friends!
• Think of overwintering geraniums as Gardening 201. Challenging yourself to overwinter plants, rather than simply grow them in their intended season, is a great way to level up your gardening skills.

How to prepare geranium plants for overwintering

The exact steps you need to take to prepare your geraniums for overwintering will depend somewhat on which of the five overwintering methods you decide to use. One fact that applies across the board is that you want the geraniums to be healthy and free from signs of insects. Get started on the overwintering process before frost damages the plants, and take care of any pests or disease—though not many affect these plants—ahead of time.

5 methods of overwintering geraniums

You have choices in how you proceed with overwintering your plants. Depending on the climate and space in your home, some of these methods will make more sense than others.

Assuming you’re overwintering more than one geranium plant, you could try several of these methods. Then next year, you can stick with the one you liked best.

Method 1: Keep a geranium as a houseplant or in a greenhouse

This is the simplest method of overwintering geraniums, and if you’re a geranium lover, you’ve probably done it before. Here’s how to overwinter geraniums as a houseplant or in a greenhouse:

1. Gently dig up each plant.
2. Put the plant in a pot with a potting mix rather than garden soil.
3. Water the geranium well, and water again about every two weeks.
4. Keep the plant in a sunny window or in your greenhouse. You can use grow lights, if needed. Geraniums want cooler temperatures indoors—60 to 65°F (15.5 to 18°C), if possible.
5. Spending a winter in lower light conditions than they’re used to will cause geraniums to grow tall and leggy. About six weeks before transplanting them outdoors, cut back the plants by one half to two-thirds, making your cuts just above the leaf nodes. Keep them in direct sunlight as much as possible.
6. If you plan to grow your overwintered geraniums in containers for the season, transfer them to larger pots to accommodate the new root growth they’ll experience come spring.

Method 2: Overwintering geraniums in a paper bag

Without the abundant windowsill, grow-light or greenhouse space for potted geraniums, overwintering dormant plants may be a better option for you. This method takes up less space:

1. Carefully dig up the geranium, and shake the garden soil from its roots.
2. Put one or two plants in a large paper bag, like one you’d get at a grocery store.
3. Keep the bag in a very cool, dry place—meaning 45 to 50°F (7 to 10°C). This might be an unheated mudroom or a somewhat-heated garage.
4. Over the winter, much of the plant will die back. In late winter, about six weeks before planting outdoors, prune away shriveled and dead parts so the firm, green stems can begin their regrowth.
5. Pot up the newly trimmed plant and water it well. Keep it in a sunny window, in a greenhouse or under grow lights.

Method 3: Hanging bare-root geraniums upside down

Before undertaking this method of overwintering geraniums, understand that the plant will lose its leaves throughout the winter and make a little bit of a mess.

1. Carefully dig up the geranium, and shake the soil from its roots.
2. Cut back the plant so it’s one-third to one-half its original height.
3. Hang from beams, rafters, a rope, hangers, etc., in a place that’s just 45 to 50°F (7 to 10°C). The plant may dry out if it’s any warmer.
4. Six weeks before transplanting outdoors, pot up the plant using a well-draining growing medium and water it well. Keep it in a sunny window, in a greenhouse, or under grow lights.

Method 4: Saving dormant geraniums in a cardboard box

Similar to the bare-root methods above, this method allows the geranium to go dormant for a winter’s nap before springing back to life when the weather warms. Follow these steps:

1. Carefully dig up the geranium, and shake the soil from its roots.
2. Cut back the plant to six inches in height. Also prune out any long roots.
3. The advantage of using a cardboard box for overwintering geraniums is the space-saving it offers. Pack all of the plants together in a cardboard box.
4. Cover the plants’ roots with moist peat moss or alternative.
5. Place the box in a cool, well-ventilated location that can withstand a little bit of water on the floor. Water the roots only when the peat moss is completely dried out.
6. Six weeks before transplanting outdoors, pot up the plant using a well-draining growing medium, and water it well. Keep it in a sunny window, in a greenhouse, or under grow lights.

Method 5: Overwintering geraniums as cuttings

Taking stem cuttings of plants is a fairly common gardening task. Use what you know about taking cuttings, and follow this process for overwintering your geraniums:

1. Using a sharp knife or pruning shears, take several three- to four-inch cuttings from the tips of the geranium shoots.
2. Pinch off the lower leaves.
3. Dip the end of each cutting in rooting hormone.
4. Plant the cuttings into a rooting mix contained in a well-draining pot. Vermiculite or coarse sand are good choices.
5. Water the cuttings well.
6. Cover the cuttings with a clear plastic bag or dome. This will create a mini-greenhouse effect with high humidity and keep the plants from wilting while they become established.
7. Keep your cuttings in a room with indirect natural light.
8. Start checking your plants in six weeks. When they start rooting, pot up each cutting individually, and keep them in a sunny window or under grow lights until you’re ready to plant or bring them outside in the spring. Water plants well. I wrote about taking geranium cuttings in this article.

What to do in the spring

After winter storage, and once you’ve done the prescribed pruning and repotting, water the plants regularly and watch your geraniums’ healthy green growth pick up. After your last frost date in the spring, begin hardening off your geraniums, bringing them outside for an increasing period of time each day and taking them back inside at night.

Plant these overwintered geraniums into your landscape or in their pots in a container garden. The plants should re-establish themselves and return to producing their abundant foliage and flowers in no time.

Troubleshooting tips

Of course there are things that can go wrong in overwintering your garden plants. Here are some things to ask yourself if your overwintered geraniums didn’t turn out as you’d hoped:

• How did the plant look when you dug it up or took the cutting? You want to start with healthy plants to give them the best chance at making it through the winter.
• Was it cool enough in the storage area for dormant geraniums?
• If you took cuttings, was their rooting medium wet enough to begin with?
• Did you prune enough of the plant—this is a tricky thing, because it’s so hard to cut back plants we love!—so it could regenerate new, healthy tissue?
• Also read this article about the causes of geranium leaves turning yellow, with advice from Niki.

One wonderful thing about gardening is that you get another chance next season. If things didn’t go perfectly as planned in your overwintering geraniums, you can make a trip to the nursery and try again.

More overwintering advice

• Overwintering plants that go dormant, like figs and brugmansia
• Geranium leaves turning yellow? 6 causes and solutions
• Saving pepper plants for next year
• For methods for overwintering tomato plants
• Storing cucamelon tubers