How to easily overwinter geraniums indoors during the winter

As the leaves begin to turn shades of orange, yellow, and crimson red and the nighttime temperatures start to fall, you might be wondering what you can do to save some of your favourite summertime blooms. One of those favourites is most likely your geraniums. These beautiful flowers are often a staple in window boxes, planter pots, garden beds, and hanging baskets, but did you know that with a little time and attention geraniums can be successfully overwintered indoors and brought back out next year to enjoy again?

In today’s blog post, we walk you through three different common techniques for transitioning your geraniums indoors and keeping them alive over the winter. Each gardener will have their own preference of how they choose to bring their geraniums indoors, but knowing what options are available to you is the first step to becoming a successful indoor geranium gardener. No matter which technique you choose, by following the advice outlined in today’s blog, you will be well on your way to creating beautiful displays of geraniums in next year’s garden from the fruits of this year’s labour!

Taking cuttings to create new plants for next year’s garden

One way to save your geraniums over the winter is to take young cuttings from this year’s established plants to create new plants for next year’s garden. Taking cuttings not only saves you space by having to take care of a much smaller plant while indoors, but it is also a great way, if you have room indoors, of creating new plants off this year’s established geraniums. Before you dive into the world of taking cuttings from your geraniums, there are a few pieces of equipment that you will need to get started. The first thing you need is clean containers or pots to grow your new plants in and some good quality potting mix. You will also need a drip tray to place underneath your potted cuttings to catch any water that may run off when watering them over the winter.

To take the cuttings, you will need some sharp pruners or a cutting knife. If you have some pruners with a tinier, needle nose blade, these may be best for getting into tighter places to take cuttings from your geraniums. Make sure to sanitize any cutting tool that you are using before taking cuttings from your geraniums so that you do not transfer any diseases from previous use of your tool in other areas of your garden. 

How to take geranium cuttings for successful rooting and winter growth

To take your cuttings, you want to make cuts just below a leaf node. Make your cutting from a stem that is green and not the older woody parts. Ideally, you want to take a cutting from your geranium that is 4-6 inches in length and has at least two leaves on the top of it that are viable and healthy looking. Once cut, you want to remove any buds, flowers, and leaves that are remaining on the bottom two inches of the stem. If you prefer, you can dip the end of your cutting in a rooting hormone to help stimulate the development of roots, but this optional as many geraniums once they make contact with the soil will start to form roots. Place your cuttings in some new potting mix and then water as needed over the winter so help stimulate new growth and healthy root development.

Keeping your geraniums indoors as houseplants

Just like many common houseplants, you can also treat your geraniums like a houseplant and move them indoors as potted plants over the winter. Before bringing your geraniums indoors, you want to inspect the plants for any insects to avoid creating an infestation indoors by bringing these bugs in with your potted geranium plants. Specific pests to watch out for are aphids, spider mites, or fungus gnats. These pests can easily breed indoors creating a whole host of problems for you later on. Some gardeners may wish to use an insecticidal soap to remove pests from their plants whereas others may prefer to give the plants a light mist or gently shake them to cause many of these bugs to fall out and move away from the plants. It’s all about personal preference here.

Tips to prevent pests and encourage new growth

If your geraniums are already in pots, a good idea is to repot them into a new indoor growing medium like a potting mix designed for houseplants. Look for one that is designed for flowering indoor plants. Repotting your geraniums into a new potting mix will help to cut down on any diseases or pests present in the soil from outside being transferred indoors. Once they are repotted, go ahead and trim back any parts of the geraniums that look weather damaged or moldy.

At this stage, you will also want to trim back any dead parts of the plants to encourage new growth. You can leave flowers on, but remove any spent blooms to help promote the long-term health of your geranium plants. Because germaniums were used to outdoor daylight conditions during the summer, when you bring them indoors, you want to recreate these conditions by either placing your plants in a sunny part of your house or keeping them under grow lights. 

Watering tips, pruning, and preparing for spring growth

When they come indoors, you will not need to water them as frequently. Once every couple of weeks should be sufficient for watering, but always keep an eye on the soil and if it seems dry, it is probably time for some more water. Remember that the roots of geraniums do not like to sit in too much water, so be sure to watch out for signs of overwatering such as stressed out leaves that have turned a deep red colour. If you see any signs that you may be overwatering, back off and let the plants dry out a bit before resuming your watering schedule.

Over the winter, your geraniums will put on growth indoors and could become a little tall. In March, inspect the growth of your geraniums and go ahead and prune them back by one half to two thirds. In a few weeks, they will put on more growth and be ready to start their transition outdoors in May or June depending on your local frost dates.

Storing geraniums as bare root plants

Before your first fall frost, dig up your geraniums or remove them from your hanging baskets and containers. Gently remove all of the soil from the roots. Gather some paper bags and place one or two geranium plants in the paper bag. Make sure before you store them in the paper bags, that they are dry to prevent the growth of mold or fungus. Store your bagged geraniums in a dry and cool location, or alternatively, you can hang them upside down in a cool and dry location. As they are being stored, the foliage and the shoot tips will die back. Don’t be alarmed as this is completely normal for this technique. In March, your stored geranium plants will look quite shriveled. At this time, trim back any dead material leaving the healthy green stem intact. 

Indoor care tips to prepare for a spring transition outdoors

After you have pruned your plants, repot them into a new, clean potting mix and give them a good watering. Place your potted geraniums in a bright place in your home such as a sunny window spot or under grow lights. Your potted geraniums will start to put on growth indoors and be ready to transition outdoors after the last frost in the spring. While growing indoors, keep an eye on their water levels and adjust accordingly. Before moving them outdoors, check your local forecast and be aware of the frost dates for your growing zone. Nothing could be worse than going to the trouble of keeping your geraniums alive during the winter to lose them to frost damage.

Final thoughts on overwintering geraniums

With a little care and attention, bringing your geraniums indoors and keeping them alive over the winter is possible. No matter which technique you use, setting your geraniums up for success indoors requires some patience, care, and careful monitoring. Until next time gardening friends, we hope that you give overwintering your geraniums a try this year. Join us on social media and let us know how your geraniums are doing indoors. Come spring when you are longing for some beautiful blooms in your garden to start off the growing season, you will be glad that you saved your prized geranium plants and gave them new life in next year’s garden!