Begonias are a diverse group of plants famous for their colorful flowers. They’re typically grown in tropical regions, making winter a challenging time to care for them. That’s why extra care is necessary to ensure these plants return the following year to grace your garden with their exquisite blooms.
You should cut back tuberous begonias to prepare them for overwintering. On the other hand, it’s best to prune fibrous root begonias before moving them indoors. Removing the dried-up leaves and stems will help your plant preserve energy during the winter and prevent risks of diseases.
In the rest of this article, I will share how to care for various types of begonias in winter. Read on to learn how to encourage your begonias to bloom again next year.
How to Care for Begonias in the Winter
Various species of begonias have different levels of tolerance to the cold, giving them distinct care requirements in the winter. The easiest way to determine what kind of care they require during the cold season is to identify their root system.
With the exception of many rhizomatous begonias and a few other winter-blooming cultivars, other begonia species have reduced metabolic activities in winter.
The other two classifications of begonias based on root system are fibrous root begonias and tuberous begonias. These two groups require special care in winter.
If you live in regions where winter temperatures seldom drop below 60 °F (15.6 °C), you can grow rhizomatous begonias in a shady area in your garden. Kept under suitable conditions, the flowers will bloom in winter until early spring.
However, despite blooming in winter, these begonias don’t tolerate frosts. They use the shorter daylight hours in winter as a stimulus for flowering, but they can die from hard frosts. As the frost on the ground thaws, the plants’ roots can become water-logged and suffer from root rot.
Rhizomatous begonias thrive best when grown indoors in pots or hanging baskets, depending on the cultivar.
In winter, you must ensure the soil or the growing substrate remains damp to continue nourishing the plants as their flowers bloom. Rhizomatous begonias don’t enter dormancy in winter and still require sufficient moisture and occasional feedings of appropriate fertilizers during the blooming period.
You can deadhead the plant by plucking off spent flowers to encourage more vibrant blooms until spring. It also helps to remove visibly damaged or drying leaves to increase the number of healthier flowers and improve the quality of new foliage.
Fibrous Root Begonias
This type of begonias (also referred to as wax begonias) is more tolerant of summer heat and full sun than other cultivars. As a result, you can grow them outdoors, where they can receive bright morning light.
However, they can be sensitive to the cold, especially when you live in an area with harsh winters. That’s why many gardeners treat them as annuals and grow new plants in the spring.
If you want to have better chances of seeing your begonias blooming again in the summer of the following year, you must move them indoors as outdoor evening temperatures drop below 60 °F (15.6 °C).
For this purpose, it’s best to grow them in pots. Choose a large pot to accommodate several years’ worth of root growth and avoid the need to re-pot your plant too frequently. A 10-inch (25-cm) tall pot with a 10-inch (25-cm) wide mouth is suitable for this type of begonia.
It’s also easy to move indoors during the cold season. You can choose a nice ceramic pot with drainage holes if you’re concerned about the aesthetics of your home.
You don’t have to cut back fibrous root begonias in the winter. However, it helps to remove drying leaves and deadhead spent flowers to allow the plants to preserve more energy while they’re less active during the cold weather.
Provide your plants with sufficient sunlight by placing them next to a bright window. However, keep the window closed to protect the plants from cold winds and fluctuating temperatures.
As long as you keep the indoor temperatures between 60 and 80 °F (15.6 and 27 °C), your mature wax begonias will thrive.
Water them when the upper 2 inches (5 cm) of the soil is dry. Remember that the soil will dry up more slowly with less sun exposure and lower temperatures, so adjust your watering schedule accordingly during the cold season.
Tuberous begonias have tender bulbs that need special attention during winter. Left underground during a hard frost, the bulbs are likely to die from the cold or suffer from root rot caused by fungal infections.
Potted begonias can be easily moved indoors for overwintering. If your begonias are buried in the ground, you’ll have to dig out the tubers before the first hard frost.
To overwinter begonia bulbs, you must cut back the leaves and stems, leaving only about 2 inches (5 cm) of the shoots above the tuber. Removing the foliage will help the bulbs store energy and gradually enter dormancy. It can also help prevent the risk of carrying diseases through the next growing cycle.
Let the remaining shoots dry for about two weeks before completely pulling them off the bulbs. You can store the bulbs in a cardboard box and leave them in a dark and dry room kept at around 40 to 50 °F (4 – 10 °C).
You can learn more about how to take care of tuberous begonias in winter by reading my other article: Complete Guide to Overwintering Tuberous Begonias in Pots
The hybrid category of begonias makes winter care a bit tricky. As mentioned, begonias are a group of diverse flower species, so it’s rather challenging to provide a general guideline regarding how to care for them in winter.
Hybrids also have distinct requirements, depending on the parent species. Your best option is to consult the garden store expert from whom you acquired your begonias. They can provide you with more thorough instructions regarding the appropriate methods of caring for your plant all year round.
It’s crucial to purchase begonias from sellers in your region so you can follow the care tips easily. Acquiring begonia varieties from an area with a different climate will make the process of caring for your plant challenging as you try to make more adjustments based on their light, water, and temperature requirements.
Soil pH can also vary from one region to another, adding to the number of things you need to consider.
Tips for Caring for Begonias in Winter
Considering the large number of begonia species and cultivars, there are various ways to care for different types of begonias. However, there are some general tips you may find helpful.
This list also summarizes the care requirements of various types of begonias:
Identify Your Cultivar
The first and most important step in caring for begonias is understanding what species you have and where you acquired it. Your supplier is the best source of information about your plant’s needs.
Non-dormant variants need constantly damp soil. Although not all of them bloom in winter, they still need adequate moisture.
Adjust your watering schedule depending on how quickly the soil dries up. Meanwhile, leave your begonia tubers to dry while in storage.
Provide Adequate Sunlight
Most begonias don’t appreciate direct sunlight, especially in winter. Place your pots or hanging baskets near an eastern window with light curtains to filter the light.
Keep a Steady Room Temperature
Begonias that don’t go dormant prefer temperatures between 60 and 80 °F (15.6 and 27 °C). On the other hand, keep your tuberous begonia bulbs in a cold room between 40 to 50 °F (4-10 °C).
Acclimatize Them Before Moving Outdoors
You should also acclimatize your begonias before moving them outdoors. Allow your begonias a few hours each day with a gradual increase to adjust to the outdoor conditions before permanently leaving them outdoors during the warm season.
Not all begonias should be cut back in winter. Depending on the cultivar, non-dormant begonias may only need to be moved indoors, and gardeners must adjust the watering schedule, light intensity, and indoor temperature to allow the plants to continue their activities.
On the other hand, tuberous begonias should be cut back in the winter to help them enter a short period of dormancy and avoid the risks of diseases spreading during storage.