Tuberous

Tuberous Begonias

There are many different tuberous types of begonias. Most produce tubers as the growing season ends and the dry, or winter season, begins. The tubers, and dormancy, help get these plants through the difficult growing periods each year.

• The ×tuberhybrida types are complex hybrids, created almost entirely from high altitude Latin American species, and so prefer cool climates to grow in.
• There are many tuberous types from other parts of the world, however, that like warmer climates. Even now, there is still much discovery in these types of plants and new information to learn.

The ×tuberhybrida types

This is the glorious flowering group of begonias, with the largest flowers, and the widest range of flower colors and shapes. These plants prefer cooler climates and long days to bloom at their peak. The culture of tuberous begonias takes a bit of practice, but is incredibly rewarding. Tuberous types are grown for their flowers, but a few types have interesting leaves as well.

The Giant Flowers

Interest in breeding and growing the very large-flowered types changes with time, and it is specialized and requires a distinct group of Begonia ×tuberhybrida genetics. Specific growing techniques are necessary. England and New Zealand Begonia societies are currently the leaders in these large exhibition types. There are even bicolor flowers and some are scented.

Tuberous for garden planting

A new seed-produced line of ×tuberhybrida begonias has been produced which yields 2-3” blooms, but on squatter, tougher plants than the giant types. The Nonstop® series and others of this type are popular with commercial growers as they are mass produced from seed, and not propagated from tubers.

Multiflora types

These are smaller flowered, but covered in blooms. They must be grown from cuttings and so are less common, however, they are stunning plants when grown in a cool climate. For more information on varieties check the National Begonia Society’s page.

Pendula types

The hanging basket forms of ×tuberhybrida are mid-sized flowers (2-3”) and when grown in cool climates are very dramatic with flowers up to 3” across and featuring brilliant colors.

Species that went into creating Begonia ×tuberhybrida include:

Bolivian Begonias

Begonia boliviensis and its cultivars have recently become more popular, and are predominantly hanging basket types. The flowers are smaller than the ×tuberhybrida types, and with thinner, longer petals featuring a distinctly different look. This type is also more heat tolerant and can be grown in warmer climates.

New species being discovered

Mark Tebbitt, Ph.D. has dedicated much of his career to exploring the Andean begonias that were used to create Begonia ×tuberhybrida, as well as species that were not discovered in that initial exploration period. Dr. Tebbitt’s book Tuberous Begonias: A monograph of Begonia Section Australes, published by the American Begonia Society, is a documentary of this fascinating group of begonias as well as the first publication of many new species and natural hybrids.

Semi-tuberous types

Another related type of Begonia is the semi-tuberous which does not have a tuber, but which form a caudex, or swelling, at the base of the stem. Most semi-tuberous have small leaves and small white flowers, however, there are a few that feature pink flowers. These make almost a natural bonsai with their swollen base and small stems and leaves.

Tuberous Species from Asia and Eastern India

There are many new, and also older, species from Africa and Madagascar, Socotra to Northern India and Asia, all the way across the continent to China. Cliff dwelling species, near desert environments, to lush tropical jungles and higher elevations. As varied as the terrain that produced these tuberous species, this appears to be where the majority of new discoveries are occurring.