Begonia is a genus of perennial flowering plants in the family Begoniaceae. The genus contains more than 2,000 different plant species, distributed primarily across tropical and subtropical regions of Africa, Asia, and Central and South America, with Africa considered the center of origin. Some species are commonly grown indoors as ornamental houseplants in cooler climates, or cultivated outside in summertime for their bright colorful flowers, which have petals but no sepals.

left|thumb|A female flower on the left and a male flower on the right, from a [[Begonia johnstonii plant.]]

thumb|right|Pink flowering Begonia

Description

With 2,000+ species, Begonia is one of the largest genera of flowering plants. The species are terrestrial (sometimes epiphytic) herbs or undershrubs, and occur in subtropical and tropical moist climates, in South and Central America, Africa, and southern Asia. Terrestrial species in the wild are commonly upright-stemmed, rhizomatous, or tuberous. The plants are monoecious, with unisexual male and female flowers occurring separately on the same plant; the male contains numerous stamens, and the female has a large inferior ovary and two to four branched or twisted stigmas. Flowers come in all colors other than blue, and range in size from tiny individual blossoms to blooms the size of dinner plates. In most species, the fruit is a winged capsule containing numerous minute seeds, although baccate fruits are also known. The leaves, which are often large and variously marked or variegated, are usually asymmetric such that their left side and right side are different sizes. The plants vary in size from less than a foot to the recently discovered Begonia giganticaulis which can exceed twelve feet (3.6 meters) in height.

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File:BegoniaBrevirimosa.jpg|Begonia brevirimosa

File:B. aconitifolia JV 250x242.jpg|Begonia aconitifolia

File:Begonia 1.jpg|A flowering begonia

File:Yellow begonia.jpg|Begonia cultivars come in many different colors, such as yellow

File:Begonia 'Parviflora' Leaf 3000px.jpg|A begonia leaf

File:Begonia blossoms maleandfemale.jpg|A pair of blossoms, male and female

File:Nautilus leaf begonia Surreybrooke farm 2012-07-1.jpg|A nautilus-leaf form of begonia

File:Begonia 0.jpg|Begonia

File:Begonia leaf.jpg|Begonia leaf

File:Cracklin Rosie begonia 02.jpg|Lucerna begonia

File:Cracklin Rosie begonia 03.jpg|Lucerna begonia

File:鐵十字秋海棠 - 溪頭自然教育園區 Begonia masoniana - Xitou Nature Education Area, Taiwan 20220309210209 01.jpg|Leaf of Begonia masoniana

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Etymology

The genus name Begonia was coined by Charles Plumier, a French monk and botanist after discovering six new species in the Antilles, which he named Begonia to honor Michel Bégon, a former governor of the French colony of Saint-Domingue (now Haiti). The first time the name Begonia was used in print was in 1700, in a publication by Joseph Pitton de Tournefort. In 1753, Carl Linnaeus merged the original six species into one (Begonia obliqua). It was published in Species Plantarum and the name has been used ever since.

Species

Selected species:

  • Begonia coccinea
  • Begonia cucullata
  • Begonia foliosa
  • Begonia grandis <small>Dryand.</small>
  • Begonia obliqua

Cultivation

thumb|right|A potted [[angel wing begonia (Begonia aconitifolia × B. coccinea)]]

The different groups of begonias have different care requirements, but most species come from tropical regions, so they and their hybrids require warm temperatures. Most are forest understory plants and require bright shade; few will tolerate full sun, especially in warmer climates. In general, begonias require a well-drained growing medium that is neither constantly wet nor allowed to dry out completely. Many begonias will grow and flower year-round except for tuberous begonias, which usually have a dormant period. During this dormant period, the tubers can be stored in a cool, dry place. Begonias of the semperflorens group (or wax begonias) are frequently grown as bedding plants outdoors. Wax begonias are very attractive, they adapt well when brought inside the house for overwintering and can live up to 4–5 years.

A recent group of hybrids derived from this group is marketed as "Dragonwing" begonias; they are much larger both in leaf and in flower. Tuberous begonias are frequently used as container plants. Although most Begonia species are tropical or subtropical in origin, the Chinese species B. grandis is hardy to USDA hardiness zone 6 and is commonly known as the "hardy begonia". Most begonias can be grown outdoors year-round in subtropical or tropical climates, but in temperate climates, begonias are grown outdoors as annuals, or as house or greenhouse plants.

Most begonias are easily propagated by division or from stem cuttings. In addition, some can be propagated from leaf cuttings or even sections of leaves, particularly the members of the rhizomatous and rex groups.

Horticultural nomenclature

thumb|Plum Paisley Begonias in a greenhouse.

To describe the flower-shape of a begonia, the following abbreviations are sometimes used:

  1. (S) Single – large single flowers, four usually flat tepals (flower part undistinguishable as sepal or petal)
  2. (Fr) Frilled, Crispa – large single flowers, tepal margins frilled or ruffled
  3. (Cr) Cristata, Crested – large single flowers, frilled or tufted center of tepals
  4. (N) Narcissiflora, Daffodil-flowered – large more or less double flowers, central tepals form "trumpet"
  5. (C) Camellia, Camelliflora – large double flowers resembling camellias, unruffled, solid colors
  6. (RC) Ruffled Camellia – camellia flowers ruffled on edges
  7. (R) Rosebud, Rosiflora – large double flowers with rose bud-like center
  8. (Car) Carnation, Fimbriata Plena – large double carnation-like flowers, tepals fringed on margins
  9. (P) Picotee – large usually double flowers like camellias, tepals with different color on margin blending with other color
  10. (M) Marginata – like Picotee only distinct non-blending line of color on margins
  11. (Mar) Marmorata, Marbled – like Camellia but rose-colored, blotched or spotted with white
  12. (HB) Hanging Basket, Pendula – stems trailing or pendant, large to small flowers single or double
  13. (Mul) Multiflora – low, bushy, compact plants with many small single or double flowers 'Non-Stop' refers to a camellia tuberous hybrid that under certain conditions will bloom 'non-stop' all year round.

Cultivar groups

thumb|right|upright|Display of (tuberous) begonias, Hampton Court Flower Show

Because of their sometimes showy flowers of white, pink, scarlet, or yellow color and often attractively marked leaves, many species and innumerable hybrids and cultivars are cultivated. The genus is unusual in that species throughout the genus, even those coming from different continents, can frequently be hybridized with each other, and this has led to an enormous number of cultivars. The American Begonia Society is the International Cultivar Registration Authority for Begonia, and classifies them into several major groups:

  • Cane-like
  • Shrub-like
  • Semperflorens
  • Rhizomatous
  • Rex
  • Tuberous and Semi-Tuberous
  • × Hiemalis/ Reiger/ Elatior Cheimantha
  • Thick-stemmed
  • Trailing/Scandent

For the most part, these groups do not correspond to any formal taxonomic groupings or phylogeny, and many species and hybrids have characteristics of more than one group or do not fit well in any of them.

AGM plants

The following is a selection from about 70 species, varieties and cultivars which currently hold the Royal Horticultural Society's Award of Garden Merit:

  • Begonia 'Benitochiba'
  • Begonia dregei
  • Begonia foliosa var. miniata
  • Begonia 'Glowing Embers'
  • Begonia grandis subsp. evansiana
  • Begonia grandis subsp. evansiana var. alba
  • Begonia 'Green Gold'
  • Begonia listada
  • Begonia luxurians
  • Begonia masoniana
  • Begonia metallica
  • Begonia solananthera
  • Begonia soli-mutata
  • Begonia sutherlandii

Culture

The cultivar 'Kimjongilia' is a floral emblem of North Korea.

The species Begonia darthvaderiana was named for the Star Wars character.

Most begonias are sour to the taste, and some people in some areas eat them. This is safe in small amounts but potentially toxic in large quantities due to the prevalence of oxalic acid in the tissues.

In floriography begonias represent a warning, "we are being watched," "this must end," "be careful," and/or "take heed."

Bian Gong<!--Q15938085--> wrote a poem titled Begonia, and Chen Chun wrote an Inscription on Begonia. Begonias are associated with the love stories of Lu You and Wan Tang as well as a legend titled 采兰杂志(采兰, so begonias are symbolic of love in China.

References

Journal articles

  • American Begonia Society
  • Phylogenetic Relationships of the Afro-Malagasy Members of the Large Genus Begonia Inferred from trnL Intron Sequences at bioone.org
  • A Phylogeny of Begonia Using Nuclear Ribosomal Sequence Data and Morphological Characters at ingentaconnect.com
  • Plants of the World Online
  • Begonia L.
  • Accepted species