Cane type begonias are some of the world's best performing and easiest begonias to grow. They are second only to wax begonias in their ease of culture, and second to none in their beauty.
By far the best-known cane-type begonias are the angel wing begonias, which grow on upright stems with interesting leaves and magnificent displays of a pendant and drooping flowers. The dragon wing begonia, another beauty, also belongs in this category. In terms of culture, these are not particularly difficult to grow and can thrive indoors, providing you meet a few basic requirements.
Light: Bright, indirect light year-round. They are not as sensitive to direct light as Rex begonias, but cannot handle the direct sunlight of a wax begonia.
Water: Water when the soil dries through the first half-inch, water thoroughly and let drain. Provide lots of humidity.
Temperature: Average to warm (and humid). As with all begonias, they do not like cold drafts and cannot tolerate freezing.
Soil: Airy, light, fast-draining soil.
Fertilizer: Use liquid fertilizer weekly at quarter strength or biweekly at half strength. During blooming in later winter or spring, switch to high-phosphorous fertilizer.
Angel wing and cane-type begonias are very easy to propagate from cuttings. When new growth begins to emerge in the spring, carefully remove a two- the three-inch leaf-tip cutting that doesn't have blooms on it and insert into potting soil, then keep moist and warm until new growth begins.
A rooting hormone will increase the chances of success, but it's not strictly necessary as they readily root from cuttings under the right circumstances. As with other hybrids, these will not reproduce accurately from seed, so only grow begonia from seed if you're sure of the seed source (a seed company, for example).
Angel and dragon wing begonias seem to really thrive when they are slightly pot-bound. When repotting is necessary, such as when the plant has exhausted its potting media or the pot is tipping over, shift to a slightly smaller pot and refresh the potting soil.
These plants can grow large (more than 36" tall), and larger plants may have somewhat brittle stems. Stake up larger plants to prevent damage to their canes as the foliage is highly attractive. Repot in early spring, just as the first flush of new growth appears. Do not attempt to repot a plant in bloom, however, as the shock will cut short the flowering.
The angel wing begonia is a Begonia x corallina, and it has served as the basis of an extensive, long-term hybridizing program. As a result, there are dozens of named hybrids, as well as various species that loosely fall into the cane-type category. Look for hybrids with attractive leaves and lots of unopened blooms.
Favorites include the 'Lucerna' and 'Carriere.' All the angel wing begonias have similar growing requirements, so treat them all the same. The dragon wing begonia (based on B. descoleana) is a similar cane-type begonia that thrives on the same treatment as angle wing begonias.
Whereas other begonias might require a more careful touch, the angel wing begonias seem perfectly suited for indoor culture, providing you can give them the warmth and humidity they require. In winter time, they can even tolerate some direct sunlight and look great on a windowsill with a collection of winter-blooming plants (including the Rieger begonia).
To keep your collection fresh, take cuttings every spring and discard leggy adult plants—they have a tendency toward legginess if conditions are less than ideal, especially if they are cold and drafty.