With more than 1,000 species in the Begoniaceae family and more than 10,000 registered hybrids, picking a favorite is difficult and it’s even harder to find the name of one you especially like. Several stand out for a variety of reasons and might be considered for introduction into your garden, landscape or home.
Begonias grow best in tropical or subtropical climates and many feature unusual leaf shapes and patterns, as well as a wide array of flower shapes and colors. These features, along with the ease of cultivation and propagation, have made begonias popular garden accents and delightful houseplants.
Three types of begonias are commonly found in Hawaii: fibrous-rooted, rhizomatous and tuberous. The names refer to their root systems, but the plants within the types are not always closely related. Most begonias grown in Hawaii are fibrous-rooted types. These varieties range in size from a few inches to several feet tall. The taller ones are often referred to as “cane-type” because of their segmented stems. Most have interesting leaf shapes and produce a profusion of colorful flowers nearly year-round.
One example, the wax begonia, or Begonia semperflorens-cultorum, makes a wonderful bedding plant. This species is popular in commercial and residential gardens, providing a low-growing mass of color in a large area, as well as a sweet, single, potted plant. Wax begonias have a wide color range, including whites, reds, pinks and oranges. Wax begonias are always flowering, producing an abundance of small blossoms in both full sun and partial shade.
Another fibrous-rooted type matching the characteristics of the cultivar Begonia x benariensis defies common name classification, though “big red” seems to fit. This shrub-like plant grows to about four feet tall and its cane-like stems produce bright red flowers and attractive bronze leaves. Unlike many begonia relatives, this specimen grows well in full sun, as long as it receives adequate water. Its colors are enhanced by sun exposure.
Though most begonia flowers are edible, some are much tastier than others. Big red’s flower has a lemony flavor that recommends it as a salad accent, as well as a tasty and colorful topping for numerous dishes, soups and casseroles, or as a simple plate decoration. It grows well from cuttings, allowing you to produce a low hedge or edge of vibrantly colorful plants quickly from a single plant.
Begonia richmondensis is a readily available fibrous-rooted begonia. It can grow to two or three feet tall and produces lovely pink flowers. It is easy to propagate but the color and flavor of the flowers are less robust than big red.
Perhaps the best known of all begonias is the angel wing, or Begonia lucerna. They have distinctive wing-shaped leaves and produce red or pink flowers.
Another fibrous-rooted begonia most gardeners are familiar with is Begonia hirtella. This species is a weedy begonia in Hawaii. It has an elliptical shaped leaf, characteristic-of many begonia species, and a flower that resembles other begonias, but a growth habit that makes it pesky. This variety grows well from seed and readily reseeds itself, especially in moist areas of a garden. Though not unattractive, this small begonia can take over a garden, if not controlled.
An outstanding species in the rhizomatous type is Begonia rex. This begonia is known for its distinctive leaves, which are often large, usually very colorful and typically sport interesting shapes. Many cultivars have been developed, offering a nearly endless variety of color markings and patterns. Most grow in mounds about 12 to 15 inches tall in the garden or in a container. They grow best in the shade, in soil that is uniformly moist but not wet. They prefer high humidity and are heavy feeders, especially when young. They make interesting houseplants when given sufficient moisture and indirect light. Though it requires a moist environment, overwatering it can be lethal.
Some Begonia rex varieties branch out and are more upright, while others are compact and creeping. Most of the varieties are slow-growing. According to the American Begonia Society, all Begonia rex are descendants of an Indian species first introduced in the 1850s. Most of them grow from a thickened stem called a rhizome, but they are distinguished from other rhizomatous begonias because of their colorful, bold leaves and growing requirements.
Tuberous begonias require cool, moist and protected environments and must be dug up and stored during their annual dormancy. They are not often grown here; they are usually discarded after a single season.
Begonias come in a wide variety of types, sizes and shapes with distinctive leaf shapes and a range of colors, making it difficult to generalize about the genus but some characteristics ,seem to unite the family. Most could be classified as herbaceous perennials. They lack woody stems, and in tropical climates, they will grow and produce new leaves and flowers year-round.
Most varieties grow best in partial shade and moist soil that drains well. Their roots rot easily in overwatered conditions and dry out when inadequately watered. When the water supply is constant, they can be lovely specimens in full sun, which enhances vibrant leaf and flower colors. The taller, cane-type varieties require occasional pruning to maintain a compact shape, and all begonias will do best in soil that is healthy and fertile. Adding compost or mulch and some additional fertility will keep your plants happy and healthy.
Most varieties you’ll find in local nurseries have been propagated through cuttings. Some varieties set fertile seeds and some can be propagated from root slips, but a four-inch cutting of the stem, rooted in a light, moist medium will most likely produce a healthy begonia clone.
Begonias are not usually plagued with pests, though a few insects may take a nibble from time to time. Chinese rose beetles, grasshoppers and the occasional slug or snail may appear. Each pest is usually deterred or controlled easily by pest-specific methods, but none usually causes lethal damage.
Begonia varieties are widely available. It’s worth a trip to several nurseries to discover their current supply. If you are seeking edible varieties, be certain to taste the flowers before you buy. Caution is always advised when tasting plant parts. Not only do you want to be sure you are tasting an edible plant, but also you want to be sure the plants have been grown organically and have not been sprayed with any toxic substances.
Enjoy the search for the perfect begonia to add to your landscape, small garden, container garden or collection of house plants. They will likely reward you with years of pleasure.
Diana Duff is an organic farmer, plant adviser and consultant.