Tuberous begonias are one of the most popular flowering plants, and it’s not hard to see why. They come in a wide range of colors, they’re relatively easy to care for, and they bloom prolifically from early summer until fall.
If you’re thinking about adding a few tuberous begonias to your garden this year, here’s everything you need to know about how to grow and care for begonias.
Plant Facts
Always include a fact table as below sample and format:
| Scientific name | Begonia Tuberhybrida |
| Common names | Tuberous begonias, hybrid begonias |
| Family | Begoniaceae |
| Plant Type | Houseplant |
| Height and Width | 12-18” wide, 6-12” tall |
| Origin | Tropical South America and Southern Africa |
| Flower colors | Red, white, yellow, pink, salmon |
| Foliage color | Medium green |
| Sun Exposure | Filtered, indirect light |
| Soil Type & pH | Well-drained soil |
| Special features | Wide selection of colors, thrive in the shade, good container or bedding plants |
How to Grow Tuberous Begonias
Tuberous begonia plants should be planted in well-draining soil in a location that receives partial sun. They can be planted directly in the ground or in containers.
If you’re planting them in containers, make sure the pots have drainage holes to allow excess water to escape.
Tubers should be planted unbranched side down about 2 inches deep. Once they’ve been planted, water them well and continue to water them regularly, keeping the soil moist but not soggy. Plants will emerge within 2-3 weeks.
Propagation
Tuberous begonia flowers are one of the most popular flowering plants. They are easily propagated from stem or leaf cuttings taken from the parent plant. It’s a good idea to take cuttings from the parent plant in late summer or early fall, after it has finished blooming for the season.
The first step is to take cuttings from the parent plant. You will need a sharp knife or garden shears for this. Cut 4-6 inch stem or leaf cuttings from the parent plant, making sure to include a node (the point where leaves are attached to the stem). Place the cuttings in a clean container filled with water.
Fill a planting container with sterile potting mix. Wet the mix thoroughly and then allow it to drain. Make a small hole in the center of the potting mix with your finger.
Gently remove each cutting from the container of water and insert it into the hole in the potting mix, making sure that at least one node is buried beneath the surface of the mix.
Firmly press the potting mix around each cutting. Water well and place in a bright, indirect sunlight location. Keep the soil moist but not soggy during rooting.
Once your cuttings have rooted and new growth appears, you can transplant them into individual pots filled with fresh potting mix. Allow the soil to dry out somewhat between watering.
Fertilize your plants every 2-3 weeks with a water-soluble fertilizer formulated for flowering plants. Deadhead spent flowers regularly to encourage continued blooming.
Soil
Soil potting mix is one of the important things you must know when it comes to begonias care.
Fortunately, tuberous begonias are relatively easy to care for, but one of the most important things to keep in mind is that they need well-draining soil in order to thrive.
Begonia tubers will rot if they’re allowed to sit in waterlogged soil, so it’s important to make sure that the soil you’re using drains well. One way to do this is to mix in some perlite or sand before planting.
Another option is to plant your begonias in raised beds or pots with drainage holes. Whichever method you choose, just make sure that the roots of your plants are never sitting in water.
In addition to being well-draining, the ideal soil for tuberous begonias should also be loose and loamy. This will help the roots of the plant to spread out and establish themselves quickly.
A good way to achieve this is by mixing in some organic matter such as compost or dry peat moss to the perennials. You can also add a slow-release fertilizer to the soil before planting to give your begonias a boost.
Pruning
If you have tuberous begonias, and you want to keep them looking their best, you’re going to have to do some light pruning.
The first step is understanding when to prune your begonias. You’ll want to wait until the blooming season is over – so anytime from late fall to early winter. This will give the plant a chance to rest and recuperate before putting out new growth in the spring.
Now that you know when to prune, it’s time to get down to business. Start by cutting back the main stem of the plant by about half. Then, cut any side stems back by about a third.
Once you’ve done that, shake or brush off any dead leaves or spent blooms. And that’s it! A few quick snips and your tuberous begonias will be good as new.
Deadhead spent blooms regularly to encourage continued flowering. To deadhead, simply snap the stem off just below the spent bloom. When fall arrives, dig up the tubers and store them indoors over winter so they can regrow next spring.
Repotting and Transplanting
Tuberous begonias are typically described as summer blooming plants, but they can actually bloom year-round if they’re grown indoors.
Whether you’re growing your begonia indoors or outdoors, you’ll want to repot or transplant it in late winter or early spring, before new growth begins. This will give the plant time to adjust to its new pot or location and get established before it has to start producing new leaves and flowers.
If your tuberous begonia is starting to look cramped in its pot or it hasn’t been repotted in a few years, it’s probably time for a fresh pot of soil. When repotting, choose a pot that’s only one size larger than the current pot—begonias don’t like being transplanted into pots that are too large. Begonias also prefer clay pots over plastic pots, as they provide better drainage.
Start by taking your begonia out of its current pot and gently shaking off any excess dirt from the roots. Next, fill your new pot with fresh Begonia Potting Mix—this mix is formulated specifically for tuberous begonias and will help ensure optimal drainage and aeration. If you can’t find Begonia Potting Mix, you can use regular potting soil mixed with perlite or sand.
Once your pot is filled with fresh potting mix, place your begonia in the center of the pot and fill in around the roots with more mix. Gently press down on the mix around the roots to remove any air pockets.
Water your plant well, making sure the water drains out of the bottom of the pot. You may need to water your plant more frequently than usual for the first few weeks after repotting, as Begonia Potting Mix tends to dry out more quickly than regular potting soil.
Transplanting a tuberous begonia is similar to repotting one—the main difference is that with transplanting, you’re moving the plant into a new location rather than just giving it a fresh pot of soil.
When transplanting outdoors, choose a spot in partial sun or shade—too much sun can cause leaf scorch on begonias. As with repotting, transplanting should be done in late winter or early spring before new growth begins.
Start by digging a hole that’s twice as wide as the root ball but not quite as deep—you want the top of the root ball to be level with (or slightly higher than)the surrounding soil so that water won’t pool around the base of the plant when it rains.
Carefully remove your plant from its current location, being careful not to disturb too much of the root ball. Place your plant in the hole and backfill around it with native soil. Water well and mulch around the base of the plant.
How to Care for Tuberous Begonias
Tuberous begonias are fairly low-maintenance plants, but there are a few things you need to do in order to ensure that they thrive. Here are a few tuberous begonia care tips.
Water
Begonias need to be kept consistently moist, but be careful not to overwater them. The best way to tell if your begonia needs water is to stick your finger into the soil; if it feels dry more than an inch below the surface, it’s time to water.
Keep the soil evenly moist, but not soggy. Allow the top few inches of soil to dry out before watering again. Begonias are susceptible to root rot, so good drainage is essential.
Sunlight
Tuberous begonias are native to Central and South America, and they thrive in shady, humid conditions. In their natural habitat, these flowers grow beneath the canopy of rainforest trees, where they receive filtered sunlight throughout the day.
When grown indoors, tuberous begonias should be placed in a spot that receives bright, indirect sunlight for at least six hours per day. South- or west-facing windows are ideal.
These flowers cannot tolerate direct sunlight, as it will scorch their leaves and flower petals. If you live in an area with very hot summers, it’s best to grow your tuberous begonias indoors or in a shady spot outdoors. Morning sun is preferable to late afternoon sun, as the heat of the afternoon sun can be too intense for these delicate flowers.
Temperature and Humidity
Tuberous begonias are tropical plants, which means that they prefer warm temperatures and high humidity. In general, begonias do best when daytime temperatures are between 70 and 85 degrees Fahrenheit, and nighttime temperatures are between 60 and 70 degrees Fahrenheit.
However, there are a few things to keep in mind when it comes to temperature. First of all, begonias are sensitive to changes in temperature, so it’s important to make sure that they’re not getting too much or too little sunlight.
If possible, try to find a spot in your garden that gets morning sun and afternoon shade. This will help prevent your begonias from getting too hot during the day.
Secondly, begonias can’t tolerate frost, so if you live in an area where the temperatures drop below 60 degrees Fahrenheit at night, you’ll need to bring your plants indoors or grow them in a greenhouse. Bring these containers or baskets indoors as soon as there is a danger of frost and you can put them outside following the last frost date to get a jump start on the growing season.
Lastly, don’t forget that Begonia tubers need a period of dormancy in order to flower properly, so if you live in a climate where it doesn’t get cold enough at night (below 50 degrees Fahrenheit), you may need to store your tubers in the fridge for a few months before planting them again.
In general, these plants do best when the air around them is kept moist—between 60% and 80% relative humidity is ideal. There are a few different ways to achieve this level of humidity:
One option is to use a humidifier in your home or office (if you’re growing your begonia indoors). Another option is to mist your plant regularly with water—I like to do this once or twice a day using a plant mister or fine-mist spray bottle.
You can also set your plant on top of a pebble tray—this is simply a tray filled with gravel or rocks that has water added to it so that the water evaporates and increases the humidity around the plant.
And lastly, Begonia tubers can be stored in perforated plastic bags filled with damp sphagnum moss; this is an especially good option if you live in a dry climate or if your home tends to be on the drier side.
Fertilizer
Tuberous begonias are relatively easy to care for once they’ve been planted. They don’t require a lot of fertilizer, but you should fertilize every 4-6 weeks using a balanced fertilizer such as 10-10-10. Be sure to follow the directions on the fertilizer package so you don’t over or under fertilize your plants.
Pest and diseases
Tuberous begonias are a beautiful addition to any garden. However, they are also susceptible to pests and diseases. Here is a list of the most common problems that begonia growers face, as well as some tips on how to prevent and treat them.
Aphids
Aphids are small, soft-bodied insects that feed on plant sap. They are often found in groups on the undersides of leaves. Aphids can cause stunted growth, yellowing of leaves, and reduced flower production. To control aphids, spray plants with water or insecticidal soap. Ladybugs and other predators can also be used to control aphid populations.
Thrips
Thrips are tiny, winged insects that feed on plant tissues. They can cause distortion of new growth, stippling of leaves, and browning of flower petals. To control thrips, remove infested leaves and flowers. You can also spray plants with water or insecticidal soap. Beneficial predators such as predatory mites can also be used to control thrips populations.
Powdery Mildew
Powdery mildew is a fungal disease that forms a white powdery film on the surfaces of leaves and stems. It can cause stunted growth, leaf drop, and reduced flower production. To control powdery mildew, spray plants with water or fungicidal soap. You can also avoid overhead watering and provide adequate ventilation for your plants.
Botrytis Blight
Botrytis blight is a fungal disease that causes grayish-brown lesions on leaves and stems. It can also cause flowers to merge together and turn brown. To control botrytis blight, remove infected leaves and flowers. You can also spray plants with water or fungicidal soap. Avoid overhead watering and provide adequate ventilation for your plants.
Common Varieties and Cultivars
There are many different varieties and cultivars of tuberous begonias, each with its own unique appearance.
There are two main types of tuberous begonias: fibrous-rooted and rhizomatous. Fibrous-rooted begonias have a shallower root system, while rhizomatous begonias have a deeper root system. The type of root system will affect how often you need to water your plant. Fibrous-rooted begonias will need to be watered more frequently than rhizomatous begonias.
Tuberous begonias come in a wide range of colors, including white, pink, red, orange, and yellow. Some have an upright growth habit while other hybrids are more sprawling. The plants can also be variegated (have multi-colored leaves). The flowers vary in size depending on the variety of plant, but they are typically around 3 inches in diameter.
There are hundreds of different varieties and cultivars of tuberous begonia, so it can be difficult to choose the right one for your garden. Here are some of the most common varieties:
- ‘Apricot Shades’ – has peach-colored flowers with ruffled edges
- ‘Garden Wonder’ – has large orange flowers with frilled edges
- ‘Nonstop Mocca’ – has salmon-pink flowers with frilled edges; one of the most heat tolerant varieties
- ‘Sundown’ – has yellow flowers with ruffled edges; blooms later than other varieties
There are many other types and varieties of begonias you can plant as well including rex begonia plants.
Conclusion
With their showy flowers and attractive foliage, it’s no wonder that tuberous begonias are such a popular choice for gardens and containers alike. Although they are typically grown as annuals, with the proper care they can be overwintered and re-bloom the following year.
Just remember to choose a sunny spot, water regularly, fertilize regularly, pinch back young plants, and protect these beautiful flowers from the first frost, and you’ll be well on your way to success!
See more: How to care for rex begonias
*image by photokrolya/depositphotos