How to Overwinter a Begonia Plant for Success

Table of Contents

1. Introduction
2. Identify Your Begonia Type
3. How to Overwinter Tuberous Begonias
4. Overwintering Begonias as Houseplants
5. Waking Up Begonias in the Spring
6. Understanding Hardiness Zones and Timing
7. Simple Troubleshooting for Winter Success
8. Conclusion
9. FAQ

Introduction

Begonias are a highlight of the summer garden, offering lush foliage and vibrant blooms that seem to glow in the shade. Whether you have the trailing blossoms of a tuberous begonia or the striking, metallic leaves of a Rex variety, these plants bring a tropical elegance to any space. One of the most rewarding parts of growing them is knowing that you do not have to say goodbye when the first frost arrives. At Longfield Gardens, we enjoy helping gardeners preserve their favorite plants so they can return even bigger and better the following year.

Overwintering a begonia is a straightforward process that saves money and allows you to keep rare or favorite varieties in your collection. The method you choose depends entirely on the type of begonia you are growing and your local climate. This guide will walk you through identifying your plants and the simple steps needed to keep them healthy until spring. By following a few basic rules for storage and care, you can ensure your begonias thrive for many seasons to come.

Identify Your Begonia Type

Before you start preparing for winter, you must know which type of begonia you have. Begonias are a diverse group of plants, and they don't all handle the cold months the same way. Some prefer to go completely dormant, while others can live happily as houseplants in a sunny window.

Tuberous Begonias

Tuberous begonias are famous for their large, rose-like flowers and are often grown in hanging baskets or shade garden beds. These plants grow from a thick, potato-like underground structure called a tuber. In their native environments, they experience a dry season where they die back to the ground to rest. In your garden, they require a dormant period during the winter. Varieties like the Begonia Hanging Golden Balcony are classic examples of tuberous types that need to be lifted and stored.

Wax and Cane-Type Begonias

Wax begonias are the small, mounded plants often used as bedding annuals. They have fleshy, succulent-like leaves that are either green or bronze. Cane-type begonias, such as the popular 'Angel Wing' varieties, grow tall with woody stems and distinctive spotted leaves. These types do not have a large tuber and do not go dormant. If you want to save these, you must bring them indoors as active houseplants. For a broader look at begonia types, see All About Begonias.

Rex Begonias

Rex begonias are grown primarily for their spectacular foliage. Their leaves come in swirls of silver, purple, pink, and deep green. Like cane begonias, these are fibrous-rooted plants that prefer to stay active year-round. They are particularly sensitive to low humidity, so they require a bit of extra attention when they move from the humid outdoors to a dry indoor environment.

Key Takeaway: Always check the root system of your plant. If you find a solid, rounded "bulb" or tuber at the base of the stems, your plant needs a dormant winter rest. If the roots are thin and fibrous, the plant should be kept as a houseplant.

How to Overwinter Tuberous Begonias

Tuberous begonias are tropical perennials that cannot survive a freeze. However, because they store energy in their tubers, they are very easy to "hibernate" in a cool, dark place. This process is often called "lifting" the tubers.

Timing the Harvest

The best time to start the overwintering process is in late autumn. As the days get shorter and temperatures drop, you will notice the leaves beginning to yellow. This is a sign that the plant is moving its energy into the tuber.

Wait until the first light frost has nipped the foliage, but do not wait for a hard, ground-freezing freeze. A light frost helps signal to the plant that it is time to sleep. Once the tops have wilted or turned brown, you are ready to dig. If you live in a region that does not experience frost, simply wait until the plant stops blooming and begins to look tired in late October or November.

Digging and Curing the Tubers

When you are ready to lift the tubers, follow these simple steps:

1. Cut back the stems: Use clean garden shears to cut the stems back to about 2 or 3 inches above the soil line.
2. Lift carefully: If the begonias are in the ground, use a garden fork to gently lift the soil around the plant. Be careful not to nick or bruise the tuber, as wounds can lead to rot. If they are in containers, simply tip the pot over or pull the root ball out.
3. Shake off excess soil: You do not need to wash the tubers. In fact, keeping them dry is better. Just gently brush away the largest clumps of dirt.
4. The curing phase: Place the tubers in a warm, dry, and shaded spot for about two weeks. This "curing" time allows the outer skin to toughen up and any remaining stem pieces to dry out and fall off naturally.

Curing is a critical step because it prevents moisture from being trapped against the tuber during storage. Once the remaining stem stubs are dry and brittle, you can gently snap them off. For a step-by-step planting refresher, see How to Plant Tuberous Begonias: Which End Is Up?.

Packing for Storage

After curing, your tubers are ready for their winter nap. The goal is to keep them dry enough that they don't rot, but protected enough that they don't shrivel up completely.

We recommend placing each tuber in its own small paper bag or wrapping them individually in newspaper. This prevents any potential rot from spreading from one tuber to another. Place the wrapped tubers in a cardboard box or a plastic bin with the lid left slightly ajar for ventilation.

For extra protection, you can pack them in a breathable medium. Common choices include:

• Dry peat moss
• Vermiculite
• Coarse sand
• Wood shavings

Finding the Right Storage Spot

Location is everything when it comes to storage. You need a spot that is cool, dark, and frost-free. The ideal temperature range is between 40°F and 50°F.

A cool basement, an insulated crawl space, or a heated garage usually works well. Avoid spots near a furnace or water heater, as these areas are too warm and will cause the tubers to sprout early or dry out. Check your tubers once a month. If you see any soft spots, remove that tuber immediately. If they look very shriveled, a light misting of water on the packing medium can help, but be careful not to overdo it. For a compact, flower-heavy example of this type, try Begonia Non Stop Mix - Bulk Offer.

What to do next:

• Wait for a light frost to kill the top growth.
• Lift tubers carefully and cut stems to 2 inches.
• Cure in a dry spot for 10–14 days.
• Pack in dry peat or paper bags.
• Store in a cool (40–50°F), dark location.

Overwintering Begonias as Houseplants

If you have Wax, Cane, or Rex begonias, you will treat them as indoor guests rather than storing them in boxes. These varieties stay green all year and will often continue to bloom throughout the winter if they get enough light.

Moving Day: Bringing Plants Inside

The transition from the Great Outdoors to the living room can be a bit of a shock for plants. To make it easier, bring your begonias inside before the night temperatures consistently drop below 50°F. Sudden changes in temperature can cause begonias to drop their leaves.

Before bringing them in, give your plants a thorough inspection. Check the undersides of leaves for hitchhiking insects. A quick rinse with a garden hose can help knock off any pests. If the plants are currently in the ground, you will need to pot them up using a high-quality, well-draining potting mix. For a dramatic cane-style example, Begonia Upright Double Bertini is a good one to know.

Light and Temperature Requirements

Indoors, begonias need bright, indirect light. A window facing east or west is usually ideal. If you only have a north-facing window, you might find that your plants become "leggy," meaning they grow long, thin stems as they stretch toward the light. If this happens, you can use a simple LED grow light to supplement the natural sunshine.

Begonias prefer the same temperatures that humans do. They are comfortable in rooms that stay between 60°F and 75°F. Keep them away from cold drafts near doors or windows, and away from the direct blast of heating vents, which can dry out their foliage too quickly.

The Importance of Humidity

The biggest challenge to overwintering begonias indoors is the dry air caused by home heating systems. Rex begonias, in particular, will show their displeasure with crispy, brown leaf edges if the air is too dry.

You can easily increase the humidity around your plants without turning your home into a swamp. One of the best methods is a pebble tray. Simply fill a shallow tray with small stones and add water until it is just below the top of the stones. Set your begonia pot on top of the stones. As the water evaporates, it creates a small pocket of humid air right where the plant needs it.

Grouping plants together also helps. As plants "breathe" (a process called transpiration), they release moisture, creating a microclimate that benefits the whole group.

Water and Fertilizer

During the winter, begonias grow much more slowly than they do in the summer. This means they need less water and very little, if any, fertilizer.

The most common mistake gardeners make is overwatering indoor begonias. Always check the soil first. Stick your finger about an inch into the potting mix; if it feels dry, it is time to water. If it still feels moist, wait a few more days. Watering correctly is a simple gardening rule that prevents root rot, which is the leading cause of plant loss during the winter.

Stop fertilizing in late fall. You can resume a regular feeding schedule in early spring when you see new leaves beginning to emerge. If you want a large-flowered container favorite, Begonia Upright Double Superba White is another beautiful example.

Key Takeaway: Indoor begonias need bright light and high humidity but very little water. Think of them as being on a "winter diet"—they are just ticking over until the sun returns.

Waking Up Begonias in the Spring

As the days grow longer in February and March, it is time to think about the upcoming garden season. This is the most exciting part of the process, as you get to see your plants "wake up" and start their new growth cycle.

Starting Stored Tubers

For your tuberous begonias, you can give them a head start by starting them indoors about 6 to 8 weeks before the last expected frost in your area. How to Start Tuberous Begonias Indoors is a helpful companion guide for this stage.

1. Check for buds: Look at your tubers. You may see small, pinkish bumps starting to form on the concave (indented) side. These are the new growth points.
2. Choose the right pot: Use a shallow pot that is only slightly larger than the tuber itself.
3. Planting depth: Fill the pot with moist potting soil. Place the tuber on the surface with the hollow side facing up. Press it gently into the soil, but do not bury it deep. Only a thin layer of soil should cover the top.
4. Warmth and light: Place the pots in a warm spot (around 70°F) with bright, indirect light.
5. Water sparingly: Do not soak the soil. Wait until you see green shoots before you begin watering regularly. Overwatering a dormant tuber before it has roots is a fast track to rot.

Refreshing Indoor Begonias

For the begonias that spent the winter as houseplants, spring is the time for a "haircut." If the stems have become long or sparse, you can prune them back to encourage bushier growth. You can also move them into slightly larger pots if they have become root-bound.

As the weather warms, you can begin to increase your watering and start using a balanced liquid fertilizer at half-strength every two weeks. This provides the nutrients the plants need to produce those spectacular summer flowers. For a classic pink option, Begonia Upright Double Roseform Pink is a lovely choice.

Moving Back Outdoors

Wait until the danger of frost has completely passed and night temperatures are reliably above 50°F before moving any begonia back outside. Just like when you brought them in, the move back out should be gradual.

Place them in a sheltered, shady spot for a few hours a day, gradually increasing their exposure to the outdoor elements over the course of a week. This "hardening off" process prevents the leaves from burning in the sun or tattering in the wind.

Understanding Hardiness Zones and Timing

When you order plants from us, we time our shipments based on your USDA hardiness zone. This ensures your plants arrive when it is safe to plant them in your local area. For more detail, see our Hardiness Zone Map.

Knowing your zone is also helpful for overwintering. If you live in Zones 9 or 10, you may be able to leave certain begonias in the ground with a thick layer of mulch. However, for most of the United States (Zones 3 through 8), begonias must be brought inside. Weather can be unpredictable, so it is always better to act a week too early than a day too late when a freeze is in the forecast. If you are comparing delivery timing, Shipping Information can help you plan ahead.

Simple Troubleshooting for Winter Success

If your overwintering doesn't go perfectly the first time, don't be discouraged. Gardening is a learning process, and even experienced gardeners lose a plant occasionally. Here are the most likely reasons for a struggle and how to fix them:

• Mushy Tubers: This is almost always caused by too much moisture. Ensure your tubers are dry before storing and that your storage medium isn't damp.
• Dry, Brittle Leaves: This usually points to low humidity. Increase the use of pebble trays or move the plant away from heat vents.
• Yellowing Leaves (on indoor plants): While some yellowing is normal as old leaves die off, widespread yellowing often means the soil is staying too wet. Let the top inch of soil dry out before watering again.
• Leggy Stems: This is a clear sign the plant needs more light. Move it to a brighter window or add a small grow light.

By focusing on these few basics—proper light, correct watering, and the right temperature—you will find that begonias are surprisingly resilient.

Conclusion

Overwintering your begonias is a satisfying way to extend the life of your garden and enjoy these beautiful tropical plants year after year. Whether you choose to let your tuberous varieties rest in a cool basement or keep your Rex begonias glowing on a windowsill, the process is simple and achievable for gardeners of all levels. At Longfield Gardens, we believe that gardening should be a rewarding journey, and successfully keeping a plant from one season to the next is one of the greatest rewards there is.

With just a little bit of preparation in the fall, you can look forward to a spectacular display of color when the warm weather returns. Take the time to identify your plants, give them the care they need during the dark months, and get ready for another beautiful growing season.

Next Steps for Winter Success:

• Identify if your begonia is tuberous or fibrous-rooted.
• Prepare your storage containers or indoor potting stations.
• Monitor the weather for that first light frost.
• Enjoy the satisfaction of seeing those first green shoots reappear in the spring!

FAQ

Can I leave my begonias in the ground over winter?

In most parts of the United States, begonias cannot stay in the ground because they are tropical plants that die when the soil freezes. If you live in a very warm climate, such as USDA Zones 9 or 10, you might be able to leave them outdoors with heavy mulch. For everyone else, lifting the tubers or bringing the plants inside as houseplants is the only way to ensure they survive. If you are unsure about your zone, the Hardiness Zone Map is the best place to start.

How do I know if my begonia tuber is still alive in storage?

A healthy tuber should feel firm and heavy for its size, similar to a fresh potato. If you squeeze it gently and it feels mushy or hollow, it has likely succumbed to rot or dried out too much and should be discarded. In early spring, you will also see small pink or white "eyes" or buds beginning to sprout on the top surface, which is a sure sign of life.

Should I wash the dirt off the tubers before storing them?

It is best not to wash the tubers with water, as adding moisture right before storage can encourage fungal growth and rot. Instead, let the tubers dry in a shaded area for a few days so the soil becomes brittle. Once dry, you can gently brush away the excess dirt with your hands or a soft brush before packing them away. If you need a quick refresher on handling tubers, see How to Plant Tuberous Begonias: Which End Is Up?.

Why did my begonia drop its leaves as soon as I brought it inside?

This is a common reaction to the change in environment, often called "transplant shock." The air inside a home is much drier and the light is less intense than it is outdoors. To minimize this, bring your plants inside before the outdoor temperatures drop significantly, and provide extra humidity using a pebble tray or by grouping plants together. New leaves that are better adapted to indoor light will usually grow back quickly.