How to Overwinter Geraniums Indoors: 3 Proven Methods

Geraniums (botanically Pelargonium) are tender perennials that we usually treat as annuals, but they will live for years if you keep them out of the cold. They die at the first hard frost, so anywhere colder than USDA zone 9 means you either buy new plants every May or bring them through winter yourself. The good news: an established geranium is far bigger and blooms far sooner than a four-inch nursery start, so overwintering a mature plant gives you a head start of six to eight weeks the following spring. This guide covers the three methods that actually work in a typical home, with the temperatures, timing, and troubleshooting you need to land them with a high survival rate.

In this guide

1. When to Bring Geraniums Indoors
2. Method 1: Dormant Bare-Root Storage
3. Method 2: Take Cuttings
4. Method 3: Grow as an Indoor Houseplant
5. Pest Check Before Anything Comes Inside
6. Common Problems and Fixes
7. Frequently Asked Questions

When to Bring Geraniums Indoors

Timing is the single biggest factor in success. Geraniums are damaged at around 28-30°F and killed outright by a hard freeze, but they also start to sulk once nights fall consistently below 45-50°F. Don’t wait for frost on the forecast — move plants in when overnight lows first dip into the mid-40s, which in most of the northern U.S. and Canada falls in late September to mid-October. In zones 7-8 you may have until early November. Mark your average first-frost date (your county extension office publishes it) and act seven to ten days ahead so you have time to inspect and treat plants without rushing.

Bringing them in early also means dealing with pests while the weather is still mild enough to do it outdoors. If you garden in containers, this is part of the same autumn routine as deciding which other tender plants to rescue — the same logic applies whether you are saving a geranium or a coleus, as covered in our guide on bringing houseplants inside for winter.

Method 1: Dormant Bare-Root Storage

This is the old-fashioned approach — the one your grandmother may have used — and it works because geraniums store water and energy in their thick, semi-succulent stems. Held cool and dark, they go semi-dormant and coast through winter on almost nothing. It is the most space-efficient method: you can fit a dozen plants in a single cardboard box or paper bag, no light required. The trade-off is that survival is less certain than with cuttings, usually landing somewhere between 50 and 80 percent depending on how steady your storage temperature is.

Step-by-step

1. On a dry day before frost, dig or unpot the plant and shake or gently wash most of the soil from the roots.
2. Cut the plant back by roughly half, removing all flowers, buds, and any soft or yellowing growth.
3. Let the plants air-dry in a shaded, airy spot for a day or two so cut surfaces callus over.
4. Place them loose in a paper bag or open cardboard box, or hang them upside down by the roots from a rafter. Avoid sealed plastic, which traps moisture and invites rot.
5. Store at 45-55°F in a dark spot — an unheated basement, root cellar, attached garage, or cool closet is ideal.

About once a month, take the plants out and inspect them. The stems will shrivel and look alarming — that is normal — but they should still feel firm, not mushy. If a plant looks bone-dry and brittle, soak its roots in water for an hour or two, then return it to storage. Discard anything that has gone black and slimy. In late winter (six to eight weeks before your last frost), pot the survivors in fresh potting mix, water them in, and move them to a bright, warm window. New growth appears within a couple of weeks, and you can move them outdoors after hardening off once frost danger passes.

Method 2: Take Cuttings

If you want the highest success rate and don’t mind giving up the parent plant, cuttings are the way to go. They take little space, root readily, and turn one geranium into several. This is also the only method that lets you keep a specific variety going indefinitely — useful if you fell in love with a named cultivar that may not be on the garden-center bench next spring. The technique is the same one used for many soft-stemmed plants; if you want a primer on what helps cuttings strike, see our comparison of rooting hormone vs. honey.

Step-by-step

1. Choose healthy, non-flowering shoots and cut 4-6 inch tips just below a leaf node with a clean, sharp blade.
2. Strip the lower leaves so the bottom two inches of stem are bare, and pinch off any flower buds.
3. Let the cut end dry and callus for a few hours to several hours — geraniums root better when the wound seals first, which reduces rot.
4. Optionally dip the base in rooting hormone, then insert each cutting an inch or two deep into a small pot of moist, gritty mix (a 50/50 blend of potting soil and perlite or coarse sand drains well).
5. Keep the pots in bright, indirect light at room temperature. Do not tent them in plastic — geraniums are prone to rot in high humidity.

Water sparingly — just enough to keep the mix barely moist — and roots will form in three to four weeks. Tug gently; resistance means they have rooted. Once established, pot them on individually and grow them on a sunny windowsill through winter, pinching the tips every few weeks to keep them bushy. By spring you will have stocky, branching young plants ready to harden off and plant out.

Method 3: Grow as an Indoor Houseplant

The simplest method is to keep the whole plant growing through winter as a houseplant. You skip dormancy and cuttings entirely, and with enough light a geranium will even bloom on and off all winter. The catch is that geraniums are sun-lovers, and most homes are far darker in winter than the plant would like, so this method demands the brightest spot you have and a little restraint with the watering can.

• Light: a south- or west-facing window is essential. With less than four to six hours of direct sun, plants stretch, pale, and stop blooming. Supplement with an LED grow light if your windows are dim.
• Temperature: geraniums prefer 60-70°F days and cooler nights around 55°F. Keep them off cold glass and away from heating vents, which dry them out fast.
• Watering: let the top inch of soil dry between waterings, then water thoroughly and empty the saucer. Cool, low-light winter conditions mean they use far less water than in summer — overwatering is the number-one killer.
• Feeding: ease off fertilizer in winter; a half-strength balanced feed once a month is plenty while growth is slow.

Before bringing the plant in, cut it back by about a third to reduce its size and remove leggy growth, and repot it only if it is badly root-bound. Pinch leggy stems through the season to keep it compact. Some leaf yellowing and drop in the first few weeks is normal as the plant adjusts to lower light; remove fallen leaves promptly to discourage disease.

Pest Check Before Anything Comes Inside

Whichever method you choose, never carry pests indoors with the plant. Whitefly, aphids, spider mites, and mealybugs all hitchhike inside and explode in the dry warmth of a heated house, with no natural predators to check them. Inspect both sides of the leaves, the stems, and the leaf joints. Spray the whole plant with a sharp jet of water, then treat with insecticidal soap or a horticultural-oil spray, coating the undersides of leaves where mites and whitefly hide. Repeat after a week to catch newly hatched eggs. For dormant-storage plants, washing the roots and stripping most foliage removes most of the problem on its own.

Common Problems and Fixes

• Black, mushy stems (stem rot/blackleg): too much moisture. Cut back to firm tissue, reduce watering, and improve airflow.
• Leggy, pale growth: not enough light. Move to a brighter window or add a grow light and pinch back the stems.
• Yellowing lower leaves: normal acclimation, or overwatering. Let the soil dry further and remove spent leaves.
• No winter blooms: expected with low light; cool, bright conditions encourage budding, but many gardeners simply let the plant rest and bloom in spring.
• Shriveled dormant plants: normal, but soak the roots if stems feel brittle and hollow.

Geraniums are tougher than they look, and any of these three methods will carry a healthy plant through to spring. If you are short on light, choose dormant storage or cuttings; if you want winter flowers, grow them on as houseplants. Many gardeners hedge their bets and use two methods on the same plant — taking a few cuttings as insurance while storing the parent dormant. For more cold-season container strategy, our urban gardening hub covers overwintering tender plants in small spaces.