Begonias represent one of the largest genera of flowering plants, containing tremendous natural diversity. Answering how many types exist is complex, as classification depends on whether one counts wild species, cultivated varieties, or hybrids. The sheer volume of forms, ranging from tiny creeping plants to small shrubs, makes the genus fascinating. Understanding the primary methods used to categorize these plants helps appreciate the scope of the Begonia family.
The Difference Between Species, Cultivars, and Hybrids
The genus Begonia contains over 2,000 officially recognized species, which are the naturally occurring, wild forms found across tropical and subtropical regions globally. These species are the foundation of all begonia types, classified using traditional botanical naming conventions.
When two different species are cross-pollinated, the resulting offspring is called a hybrid, combining genetic traits from both parents. Reproduction of these hybrids must be vegetative—using cuttings—to ensure the new plant is identical to the parent.
A cultivar, short for “cultivated variety,” is a specific hybrid or naturally occurring variant intentionally selected and named for a desirable, stable trait, such as a unique leaf pattern or compact growth habit. The number of named cultivars and unnamed hybrids extends into the tens of thousands, making a definitive total count of all begonia “types” impossible. The vast majority of begonias sold commercially are complex hybrids and named cultivars, not the original wild species.
Begonia Classification by Stem and Root Structure
Horticulturalists typically group begonias into categories based on their root and stem structure, which dictates their overall growth habit. This method provides three primary structural types: Cane-like, Rhizomatous, and Tuberous. This classification system is highly practical for gardeners, as each type is distinct in how it stores resources and grows.
Cane-like begonias are identified by sturdy, upright stems that feature prominent, swollen nodes, giving them a segmented, bamboo-like appearance. These types often grow quite tall and tend to be free-flowering, producing large clusters of blooms. The popular “Angel Wing” begonias belong to this category, named for their elongated, wing-shaped leaves that frequently display silver spotting and reddish undersides.
Rhizomatous begonias, considered the largest group in cultivation, are characterized by a fleshy, thickened stem called a rhizome that creeps horizontally along the soil surface. This specialized stem functions as a storage organ for water and nutrients, contributing to the plant’s low-growing, mounding habit. While they do produce flowers, this group is primarily valued for its spectacular and diverse foliage, which can be star-shaped, round, or spiraled with varied colors and textures.
Tuberous begonias are distinguished by a subterranean, starchy storage organ called a tuber. This allows the plant to enter a dormant period, typically during winter or dry seasons. This group includes many hybrids known for producing large and showy flowers, sometimes up to six inches across, in a wide array of vibrant colors. These begonias are frequently grown as annuals or are dug up and stored over winter in regions experiencing frost. The flowers are monoecious, meaning the male and female blooms appear separately on the same plant; the larger, often double, flowers are the male ones.
Distinctive Foliage and Flowering Groups
While structural classification is systematic, begonias are also grouped by their most prominent ornamental feature, which is more useful for consumers choosing a plant. Rex Begonias and Wax Begonias are two examples of groups marketed for their visual appeal.
Rex Begonias, often sold as King, Fancy-Leaf, or Painted-Leaf Begonias, are a complex group of hybrids known as the Begonia Rex Cultorum. Although structurally a type of rhizomatous begonia, they are categorized separately because their leaves are the main attraction. Their small, pinkish-white flowers are often considered insignificant. Their stunning foliage features intricate patterns, bold spirals, and a metallic sheen in shades of silver, purple, pink, and deep green.
Wax Begonias, also known as the Semperflorens Cultorum Group, are the most commonly grown bedding plants in the begonia family. This group is characterized by a fibrous root system and fleshy, succulent stems, making them tough and heat-tolerant. The name Semperflorens means “always flowering,” reflecting their ability to produce continuous clusters of white, pink, or red blooms from spring until the first frost. They possess glossy, rounded leaves that can be bright green or a dark bronze; the bronze-leaved varieties often show greater tolerance for direct sunlight.