How to Overwinter Begonias: 3 Tips for Overwintering Begonias

Overwintering is the process of ensuring a plant survives the winter by protecting it from the cold and providing the extra light needed in the long, dim winter months. Ornamental plants, such as begonias, feature flowers over the summer, but the blooms die off in cold weather. If properly cared for, begonia plants, usually treated as annuals, can be perennial plants and last for many years.

There are many begonia species and ways of categorizing them, but they generally fall into these categories:

1. 1. Wax begonias: As their name might suggest, wax begonias (Begonia x semperflorens-cultorum) often have leaves that appear waxy or glossy. They tend to be hardy plants and come in a wide range of colors.
2. 2. Tuberous begonias: Known for their big, showy flowers, tuberous begonias (Begonia x tuberhybrida) require shaded environments and temperate climates.
3. 3. Rex begonias: Rex begonias (Begonia rex-cultorum) have colorful foliage that are streaked in colors from bright pink, to yellow, to violet, to white, and silvery-tones.
4. 4. Cane begonias: Also called angel-wing begonias, cane begonias are named for their stiff and sturdy stems. Cane begonias can grow much taller than other types of begonias—sometimes exceeding eight feet in height.
5. 5. Rhizomatous begonias: Rhizomatous begonias come in a wide range of colors, shapes, and sizes. They don’t get very tall but can extend wide because they grow from rhizomes, a type of stem that grows horizontally just below the soil’s surface.

Overwintering is the process of ensuring that plants survive the changing seasons. You can use a few different methods, depending on the specific set of conditions available and type of begonias:

1. 1. Leave your begonias in the garden. This method is highly dependent on your local climate. In warm climates where the winter frosts are rare to nonexistent, you can leave begonias to go dormant on their own and they will come back as annuals every year. The changing season will usually force dormancy, especially in tuberous varieties. If this occurs, it’s good to cut back any dead or withered foliage, trimming the plant back to the ground.
2. 2. Overwinter potted begonias. If your begonia plants grow in pots, overwintering is a simple matter of bringing them inside. Try to get begonias indoors before the temperature drops below sixty degrees Fahrenheit. Fibrous varieties can make excellent houseplants, provided they have enough light exposure and moisture— keeping up the humidity levels inside is a helpful measure to take. It is best to leave tuberous-rooted begonias dormant. You can also bring rhizomatous begonias, which grow best in pots, inside to live out the winter as houseplants. They will likely lose their foliage initially, but with weekly watering and a good source of indirect sunlight, begonias will typically produce new growth in a few weeks.
3. 3. Dig up tubers. You can overwinter tuberous begonias by digging up, drying, and storing the begonia tuber through the cold season. To succeed, the tubers must be indoors before the first frost, preferably before temperatures drop below fifty degrees outside. Dig up the tubers with a garden fork, as it allows careful clearing out of the surrounding soil without cutting into any portion of the tuber. You can also carefully use a spade. It’s good practice to give at least a foot of space outside the plant. After safely removing the tuber from the soil, shake it gently to discard excess dirt. Allow the tubers to dry out by leaving them out in the dry air over a few days. Then, transfer to a cardboard box or paper bag, and keep them in a cool, dark, dry location for the winter.

The process of overwintering begonias is relatively straightforward, but having a few additional guidelines and extra gardening tips is an excellent way to boost your chances of keeping your begonias alive through the winter:

1. 1. Pack the tubers snugly. When storing the tubers, whether in a cardboard box or a paper bag, it’s a good idea to pack them with peat moss, coco coir, sawdust, perlite, vermiculite, or another light, absorbent material that will keep them dry and separate them from each other. This method will allow you to pack several bulbs in one box.
2. 2. Transition the plants gradually. After the last frost, you can move your potted begonias outdoors in early spring. Place them in the shade, and ensure they’re protected from wind, rain, and steep temperature changes. Then, after a couple of weeks of acclimation, you can move them into their usual spots.
3. 3. Replant the tubers. If you preserved your tuberous begonias, you should wait until the soil temperature has reached sixty degrees Fahrenheit before replanting them—a soil thermometer is handy. You can also start them early, from six to eight weeks before moving them outside, by putting them in a shallow container with a loose, well-draining potting medium and lightly, regularly watering them. They are susceptible to root rot, so make sure they aren’t in standing water at any point.

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