Begonias

With fierce competition for light and nutrients on the rainforest floor but plenty of water, begonias don’t waste effort on deep roots — instead they grow large leaves to catch maximum light.

In 2020 over 90 begonia species were on the IUCN list, of which 40 species are either endangered or critically endangered due to habitat loss and illegal collection.

Begonias have been collected in Africa, South and Central America, India, southern China, Vietnam, Malaysia, the Philippines, Indonesia and Papua New Guinea. The only locations where they are not found are Australia and Polynesia.

Although Begonias face fierce competition for light and nutrients on rainforest floors the habitat is inherently moist. Instead of putting energy into growing deep roots they have adapted to grow large leaves which help them to catch as much of the low light as they can.

Water-loving Begonias may also be found in the wild on steep slopes or rocks near waterfalls and streams, or in damp caves. There are even epiphyte Begonia species’ that can be found clinging to trees and branches.

Begonias have asymmetric leaves, and their flowers are monoecious, which means that both male and female flowers are found on the same plant. The Begonia’s ability to adapt to environmental triggers over many thousands of years has led to them being ideal for cross-breeding and propagating, and thousands of hybrids have been bred both commercially and by hobbyists.

‘Begonia’ is both the common name and the botanical name for all members of the genus. Begonia varieties have been separated into nine distinct sub-groups to make them easier to describe. Their differing habits offer many and varied blooms, some of which are lightly fragranced, and striking foliage that is often textured, which makes them an exciting plant for home gardeners who want to get to know a single plant family.

Begonia varieties:

• Rhizomatous: Compact and grown for their highly patterned and textured leaves and stems, Rhizomatous Begonias grow from a ground-stem or rhizome

• Rex: Rex Begonias are a type of Rhizomatous Begonia grown for their dramatic, multi-coloured foliage

• Semperflorens: One of the Begonias that can be eaten raw, Semperflorens are used as bedding plants because of their abundance of flowers

• Shrub: This group branches often, has a low-growing habit and interesting foliage which may be hairy or velvety

• Thick-stemmed: One of the lesser-known varieties, if you like foliage and branches they may be the plant for you. They do not flower often, need more room, like more light and have deeper roots than other Begonia types.

• Trailing: These Begonias are grown as ground covers and climbing plants. They are ideal in hanging baskets because of their trailing habit and will also grow up posts and trellis’ with a bit of help.

• Tuberous: Tuberous Begonias have been bred to have large, eye-catching flowers. Some of them die back in winter and emerge from their tubers again in Spring

• Elatior: This Begonia type is the result of cross-breeding experiments with winter flowering species’ that could be grown indoors in the early 1900s. They now grow year-round and are prized for their blooms

• Cane: The Cane Begonias have long stems with swollen nodes that resemble bamboo. They are grown for both their foliage and their flowers.

Whether you’re looking for an indoor plant that grows in low light, a little something for containers in a small space or a shallow-rooted bedding plant to add some potted colour to a shady spot in the garden, there’s a Begonia for you.

Are Begonia flowers edible?

Yes! The rumour is true, First Nations Peoples have been using Begonias in their plant medicines for thousands of years, and the leaves and flowers of some species are edible too. They have however adapted to produce high levels of oxalic acid to protect themselves from insects and herbivores, so please make sure to check that yours is edible before you nip out to the garden to forage a salad.

Bright ideas for potted colour

If you’re always wondering what other uses you can put your plants to, oxalic acid is a mordant used to fix plant dyes, so there’s potential for your Begonias to yield even more joy and colour when you prune or uproot them at the end of the season.

In the hard to find Dyes from Plants of Australia and New Zealand (1971), Joyce Lloyd says scarlet Begonia flowers yield a bright pink when mordanted with alum. If you decide to experiment, remember to wear gloves, keep your dye pots separate from your food pots and work in well-ventilated spaces.

This rare Begonia likes to live dangerously, growing on steep, moist limestone cliffs in the semi-shade of a broadleaf forest near the mouth of Palawan's Puerto Princesa underground river. B. Taraw was also found in a cave semi-shaded by tropical forest nearby.

The epithet 'Taraw' means Kast Limestone in the language of the Tagbanua people of the island.

Although protected due to its location in a National Park, B. Taraw is critically endangered and listed on the IUCN Vulnerable list due to the threat of rapid habitat loss in the Philippines.

B. Taraw has fleshy, broadly ovate leaves and grows to 10cm. Its leaves are discolourous – mid-green on top and red underneath.

Clusters of flowers in pink to white shades are arranged in cymes 50cm above the leaves with a central male flower and lateral female flowers up to 2cm in size with 3-winged ovaries. The female flowers branch up to six times, maturing successively, and there is a ring of fleshy hairs at the base of the flower's stem. The fruit of this tenacious Begonia is a 3-winged papery, pale brown capsule.

A single B. Taraw specimen has been cultivated in Taiwan and flowered from summer to autumn. The plant was fruiting and flowering in November 2011 when the first specimens were collected.

This rare Begonia likes to live dangerously, growing on steep, moist limestone cliffs in the semi-shade of a broadleaf forest near the mouth of Palawan's Puerto Princesa underground river. B. Taraw was also found in a cave semi-shaded by tropical forest nearby.

The epithet 'Taraw' means Kast Limestone in the language of the Tagbanua people of the island.

Although protected due to its location in a National Park, B. Taraw is critically endangered and listed on the IUCN Vulnerable list due to the threat of rapid habitat loss in the Philippines.

B. Taraw has fleshy, broadly ovate leaves and grows to 10cm. Its leaves are discolourous – mid-green on top and red underneath.

Clusters of flowers in pink to white shades are arranged in cymes 50cm above the leaves with a central male flower and lateral female flowers up to 2cm in size with 3-winged ovaries. The female flowers branch up to six times, maturing successively, and there is a ring of fleshy hairs at the base of the flower's stem. The fruit of this tenacious Begonia is a 3-winged papery, pale brown capsule.

A single B. Taraw specimen has been cultivated in Taiwan and flowered from summer to autumn. The plant was fruiting and flowering in November 2011 when the first specimens were collected.