There are several ways to overwinter geraniums (Pelargoniums) from your garden. With some newspaper, a cardboard box, paper bag, or a sunny windowsill, you can keep these tender perennials for the winter and have fresh blooms next spring and summer. Iโll walk you through the options and provide winter care tips.
If you have trees in pots, this shows how to overwinter a potted tree to keep it safe for the winter.
Overwintering Geraniums
Geranium | Genus: Pelargonium
The Geraniaceae family of plants includes Geranium (430 species), Pelargonium (280 species) and Erodium (80 species).
Pelargonium common names include: zonal, scented, ivy-leafed, and Martha Washington geraniums.
Misnomer: We commonly refer to Pelargoniums (Pelargonium x hortorum) as โgeraniumsโ but thatโs not their botanical name. At this point it’s more like a misplaced nickname that won’t go away.
Geranium (Pelargonium) Growing Tips
Long-living flowering annual (tender perennial)
โข Hardiness zones: 10 to 11
โข Full sun
โข Soil: well-draining
โข Propagation: grow from cuttings or division
โข Cold climates: overwintering tips
โข Grow indoors or outdoors
Gardeners have all sorts of ways to keep geraniums over the winter and regrow them in spring. I like to save particularly beautiful specimens, knowing I may not be able to find similar ones at plant nurseries next spring.
Some gardeners save them as family keepsakes, both overwintering the plants and taking rooting cuttings to ensure they survive for years.
There is some name confusion with these plants. The Geraniaceae family of plants includes Geranium (430 species), Pelargonium (280 species) and Erodium (80 species).
We commonly refer to Pelargoniums (Pelargonium x hortorum) as โgeraniumsโ but thatโs actually another genus in the family. Iโm using the two words interchangeably here.
Many Pelargoniums grow as bush-type plants with thick, succulent stems, which is why they are good candidates for winter storage.
The flowers are traditionally red, salmon, violet, white, or pink.
While they are sold as annuals, they are actually tender perennials, and tolerate temperatures down to about 45ยฐF (7ยฐC) while actively growing. Their sweet spot is between 55ยฐ-65ยฐF (12ยฐ-18ยฐC), which is ideal for indoor growing as well.
Contents
4 Easy Ways to Overwinter Geraniums
1Bring Inside as Houseplants
If you have room for the pots in a sunny location, you can bring your potted geraniums (Pelargoniums) into your house for the winter.
While they need sun, they do best with moderate temperatures 55ยฐ-65ยฐF (12ยฐ-18ยฐC). I have great success with a west-facing window that is slightly drafty, keeping the air around them a little cooler than the rest of the house.
Dig Up and Repot if Desired
There is some preparation necessary to ensure they are happy, healthy, and insect-free.
- If your geraniums are in the ground, dig them up and pot them about six weeks before first frost.
- If they are already in pots, you can repot them if desired but hard prune and do your bug inspections first (see below).
- While potting, trim back any super long roots or any gnarly root balls.
- Use potting mix suited for flowering plants in containers.
Tag by Colour
- Sort your geraniums by color and tag them if you want to keep track.
Hard Prune
- It is commonly advised to cut back the entire plant by one-third to one-half.
- You should also remove any dead, damaged, moldy, unhealthy, or diseased parts.
- While this hard pruning is best in the long run, you can try keeping any buds or flowers if the plant is otherwise nice and healthy.
Bug Inspection
- Check for aphids, spider mites, fungal gnats, and other sneaky beasts.
- Apply an insecticidal soap spray made specifically for transitioning plants indoors.
Bring Inside
- Water moderately, and get your plants settled in a sunny but not hot location.
- See How to Grow Geraniums Indoors as Houseplants for more tips.
Winter & Spring Care
- Keep moist, not dry or damp.
- Room humidity at 50% is optimum (without risking mold)
- Pinch back shoots.
- Fertilize lightly in spring.
- Begin to harden off (prepare plants for life outdoors) a few weeks before last frost.
2Take Cuttings
Instead of bringing the entire plant indoors for the winter, you can also take cuttings. This is a good solution if space indoors is limited, or you want more plants.
For step-by-step instructions, see How to Take Cuttings from Geraniums.
I’ve included videos (from other gardeners) for those who learn better this way. Keep in mind that each gardener has their own methods and they may vary (but still work) from what I’ve advised here.
3Cool Storage
I find this method is unreliableโsome years the geraniums do fine, other years they donโtโbut itโs not a bad choice if you just want an easy option and donโt mind if the plants die.
Keep the plant in its container, prepare it, and place in cold storage. The idea is to let the plant go dormant for the winter without letting the plant freeze or potting mix dry out. The stems and foliage can be cut back and/or protected with straw mulch if there is a chance of freezing.
Youโll need a cold space like a garage, shed, cold cellar, or unheated greenhouse or basement that does not dip below freezing. A good range is 34 to 40ยฐF (2 to 4ยฐC).
Prepare For Storage
To get started, clean up your potted geraniums by removing dead, damaged, moldy, diseased parts, and cutting the entire plant back by one-third to one-half.
Check and treat for insects.
Water deeply and place in storage.
I like to place some support rods in the soil and hang a blanket over the whole thing or cover in straw mulch as mentioned.
Winter & Spring Care
- Check monthly or more often and remove any moldy or dead parts.
- If you’re concerned conditions are too cold, use a simple kitchen thermometer with a probe to measure the temperature at root level.
- Water lightly every now and then.
- In spring, gradually reintroduce to outdoor light and normal watering routine.
Related: More Tips For Overwintering Plants
4Dormant Bare Root Storage
This is a popular method that has been done for generations. Youโll need a garage, shed, cold cellar, or unheated basement that does not dip below freezing or go beyond 45ยฐF.
We call it โbare rootโ storage because the plant is removed from the soil, pruned, and placed in cool storage. Pelargoniums can handle this because of their thick, succulent roots, which survive so long as they do not dry out or become diseased.
Hereโs what you do.
Label Your Plants by Color
- First, plan to label your plants if you want to keep track of the flower colors.
- You could store them in groups by color or place tags (loosely) around their roots.
- I write the details on little strips of cardstock and staple it like a wristband around the stems.
Dig Up or Unpot
- Gently shake off all loose soil.
- You can air dry the plant for a few days and then shake off more soil.
Storage
Whatever you do, you donโt want the plants to get damp or sit on moisture because they are prone to mold.
You do, however need to keep them watered, and not allow them to dry out (theyโll die).
There are several options:
- Suspend the plants from ceiling hooks.
- Place in paper bags and hang from hooks or set on shelf.
- Wrap in newspaper and sit on shelf.
- Place in cardboard box.
As far as I can tell, the advice to always hang the plants upside-down for better results seems to be a wivesโ tale.
Winter & Spring Care
- Check on your plants every week or two. I put a reminder in my computer calendar.
- The plants should remain firm, not withered or unhealthy looking.
- Remove any mold, black parts, or dead matter.
- Soak in warm water for one to two hours each month.
- Allow to dry before returning to bags, newspaper, or box.
Six Weeks Before Last Frost
Reviving Dormant Geraniums
- Prune as needed and remove any excessively long roots.
- Pot in moist potting mix, burying the plant two leaf nodes deep (these will form roots).
- Gradually re-introduce to light.
- New growth should appear in 1-2 weeks.
- Gradually introduce to life (harden) outdoors in anticipation of last frost.
Watch Geranium Tips
Resources
- Overwintering Geraniums | Iowa State University (PDF)
- How to Take Geranium Cuttings | Thompson & Morgan
- How to Buy and Care for Pelargoniums | Oregon State University Extension Service
Frequently-Asked Questions
Yes, you can overwinter geraniums (Pelargoniums) anywhere. It’s the storage conditions that matter. As long as the plants do not freeze or dry out, they can survive the winter.
You can keep geraniums (Pelargoniums) as houseplants, propagate cuttings, or store the entire plant or just the bare roots, in a dry, cool location.
No, geraniums (Pelargoniums) are tender perennials, hardy down to about 45ยฐF (7ยฐC). True geraniums (genus geranium) like cranesbill are hardy perennials.
Yes, you can take cuttings from geraniums (Pelargoniums) any time in the growing season and root them for new plants.
Fungus Gnats
If you notice tiny mosquito-like insects flying around your houseplant, it may be fungus gnats.
You can trap the adults using these sticky yellow cards which will in turn prevent females from laying eggs.
This has more ideas for garden jobs to take care of on a sunny fall afternoon.
~Melissa the Empress of Dirt โ
How to Overwinter Geraniums
Equipment
Supplies & Materials
- 1 Geranium plant (Pelargonium) Healthy
- 1 Paper bag or cardboard box
Instructions
- Remove plant from container and gently shake off soil.Air dry for a few hours if needed for more soil to fall off.
- Remove any dead or dying leaves or flowers.
- Place plant in paper bag or cardboard box in cool, dry location.
- Check every two weeks to ensure plant remains healthy looking not moldy.
- Six weeks before last frost, return to clean container with fresh potting mix. Water.
- Gradually reintroduce to light and warmth indoors.New growth should appear in 1-2 weeks.
- Gradually reintroduce to outdoors after last frost.