How to Overwinter Begonias: Dig, Store, and Replant for Bigger Blooms

Tuberous and wax begonias rank among the most popular bedding and container plants for summer gardens. A single well-cared-for plant can keep blooming for ten years or longer, but only if it survives the gap between fall and spring. Gardeners in hardiness zones 8 and higher, where winters stay warm, can grow begonias year-round or cut them back in autumn and let them regrow when the weather warms. Gardeners in zones 7 and lower need a storage plan. The basics of overwintering garden plants indoors apply to both types, with one key difference: tuberous begonias go dormant and store dry, while wax begonias keep growing as houseplants.

Know Your Begonia Type Before Winter Arrives

The method that works depends on the type and cultivar, so identify what you grow before the first frost. All begonias prefer steady temperatures and react poorly to wide swings, but the winter treatment splits into two clear paths.

Tuberous Begonias: Dig and Store

Tuberous begonias (Begonia x tuberhybrida) grow from fleshy underground tubers that go fully dormant in winter. In zones 7 and below, dig them before frost, dry them, and store the tubers above 45°F. Keep them dry through the cold months; moisture is the main cause of rot in storage. The same tubers can be started again indoors in late winter for an earlier bloom.

Wax Begonias: Pot and Bring Indoors

Wax begonias (Begonia semperflorens) have fibrous roots and do not produce tubers. They can be potted in fall and grown indoors through winter, or kept in a cool, frost-free garage until spring. Wax begonias need bright, indirect light as houseplants and a steady hand with watering: the top inch of soil should dry out between drinks.

Zone Check: Where Each Type Survives

Zones 8 and higher: begonias can overwinter in the ground, often with a simple autumn cutback. Zones 7 and lower: tuberous types must be lifted, and wax types must come inside or into a protected garage. Zone 7 sits on the line, so a mild winter can carry some plants through, but a hard freeze will not forgive a late decision.

How to Store Tuberous Begonias Step by Step

Tuber storage is a sequence of small tasks that protect the plant through months of dormancy. Do the work before the first hard frost, and check the tubers occasionally through winter. For a refresher on keeping the plants healthy all season, the basics of caring for begonias cover the watering, light, and feeding habits that produce strong tubers in the first place.

Dig Before the First Frost

Watch the forecast and dig tubers before the ground freezes. Frost blackens the foliage and signals dormancy, but frozen soil can damage the tubers themselves. Use a garden fork to lift from the outside of the root zone so you do not slice through the tubers. Shake off loose soil and cut the stems back to about 1 inch.

Dry, Clean, and Store the Tubers

Let the tubers dry in a sheltered spot for one to two weeks until the skins firm up. Remove remaining soil, then pack the tubers in a box or paper bag with dry peat moss, vermiculite, or sawdust. Keep them above 45°F in a basement, garage, or closet that stays frost-free. Check monthly and remove any tuber that shows soft spots or mold before it spreads to the rest of the batch.

Ideal Storage Conditions

Temperature and humidity do the work in storage. Aim for 45 to 55°F, which keeps tubers dormant without chilling injury. Humidity should stay low: packing material should feel dry, not damp. A tuber that shrivels is too dry, while one that rots is too wet. Adjust the packing and the location until the tubers hold firm through February.

1. Dig tubers with a garden fork before the first hard frost.
2. Cut stems back to about 1 inch and shake off loose soil.
3. Dry tubers for one to two weeks in a sheltered, airy spot.
4. Pack in dry peat moss, vermiculite, or sawdust.
5. Store above 45°F and inspect monthly through winter.

Overwintering Wax Begonias Indoors

Wax begonias skip dormancy entirely. They keep their leaves and keep growing slowly, so they need light, water, and occasional feeding through the winter months.

Pot Up Before Frost

Dig wax begonias before frost and pot them in containers with fresh potting mix, or move plants that already grow in pots straight indoors. Check the undersides of leaves for pests before bringing them in, since insects multiply fast in warm rooms. A quick rinse under the hose removes most hitchhikers.

Light, Water, and Feeding Through Winter

Place pots in bright, indirect light, such as an east-facing window or a spot a few feet back from a south window. Water when the top inch of soil dries, and cut feeding to once a month or stop entirely from November to February. Growth slows in low light, so the plant needs less food, not more.

Signs Your Plant Is Struggling

Leaf drop usually means the light dropped too fast when the plant came indoors. Leggy stems with wide gaps between leaves mean the window is too dim. Yellow lower leaves often mean overwatering. Fix light first, then adjust watering, and the plant settles into a winter rhythm.

• Leaf drop: raise light levels gradually when moving plants indoors.
• Leggy growth: move to a brighter window or add a grow light.
• Yellow lower leaves: let soil dry further between waterings.
• No new growth: normal from November to February; growth resumes as days lengthen.

Spring Wake-Up: Replant for Bigger Blooms

Spring reverses the process. Tubers wake up indoors, plants harden off, and everything moves back outside once nighttime temperatures hold above 50°F. The timing matters: plants set out too early sit in cold soil and sulk, while plants set out on schedule grow without a pause.

Start Tubers Indoors in Late Winter

About six to eight weeks before the last frost, set stored tubers in shallow trays of moist peat or potting mix, hollow side up, and keep them warm and bright. Shoots appear in two to four weeks. Pot each tuber once shoots reach about 2 inches, then grow them on indoors until planting time. This head start is what turns a modest tuber into a plant covered in flowers by midsummer.

Harden Off and Plant Outside

Replant begonias only after nighttime temperatures stay above 50°F. Move plants outside for a few hours a day, lengthening exposure over a week so leaves adjust to sun and wind. Plant tuberous begonias at the same depth they grew before, with the hollow side up, in rich, well-drained soil. Space them 8 to 12 inches apart, water in, and add a layer of mulch to hold moisture.

Common Overwintering Mistakes and How to Avoid Them

Most overwintering failures trace back to a few repeatable errors. Fix these and the plants come through winter reliably.

Storage Rot from Excess Moisture

Moisture kills more stored tubers than cold does. Tubers packed while still damp, stored in a humid basement, or checked too rarely develop soft spots and mold. Dry tubers fully before packing, use dry packing material, and inspect monthly. Remove any soft tuber immediately so rot does not reach its neighbors.

Plants That Get Too Little Light Indoors

Wax begonias moved indoors often suffer a sudden light drop. The plant reacts with leaf drop and stretched stems. Give them the brightest indirect light the house offers, keep them out of cold drafts near windows, and move them back outside gradually in spring. A south-facing room with sheer curtains gives most varieties enough light to hold their leaves through the darkest months.

Overwintering is a small seasonal task with a long payoff. Ten minutes of digging in October and a monthly check through winter bring back the same begonias you planted last spring, already adapted to your garden and ready to bloom harder than the year before.