The genus Begonia is one of the top ten most speciose angiosperm genera with about 1400 species divided into 66 sections.They are found in moist tropical and subtropical regions around the world with the most diversity in Asia (600+ species) and the Neotropics (600+ species), fewer African species (150+, about a third of which are endemic to Madagascar and nearby islands); but no presence in Australia tropical forests.Research suggests that the begonias originated in Africa relatively recently (16-43 million years ago) and colonized Asia and the New World in separate events (Tebbitt 2006 and references within).
Begonia species are terrestrial (sometimes epiphytic), shade-loving herbs, shrubs and lianas. Species range in size from a few inches to over 12 feet in height. Terrestrial species in the wild are commonly upright-stemmed, rhizomatous, or tuberous. The leaves are usually asymmetric, and often have color variegation.Although there are some exceptional annual and dioecious species, most begonias are perennial and monoecious (male and female flowers on the same plant).Male flowers have numerous stamens; female flowers have a large inferior ovary and two to four branched or twisted stigmas. Most species produce a “winged” fruit containing hundreds of tiny seeds, adapted for wind dispersal, although others produce fleshy animal-dispersed fruits and some (e.g. sections Platycentrum and Parvibegonia) show unique morphologies adapted to rain dispersal (Wikipedia 2014; Tebbitt et al. 2006).
The range of begonia flowers, foliage colors and sizes and resilience are diverse, and have been hybridized and cultivated for gardens and homes in many parts of the world. Even in temperate climates, begonias are grown outdoors as annuals, or as house or greenhouse plants.The genus is unusual in that many species throughout the genus, even those from different continents, can hybridize with each other and have been cultivated for hundreds of years, which has given rise to an enormous number of cultivars (classified into cultivar groups, which don’t reflect any phylogenetic or taxonomic structure). These hybrids cannot reproduce sexually; most are propagated vegetatively from leaf cuttings or leaf sections.
There is concern about extinction of wild begonia species; the IUCN includes 48 species on the red list of threatened species, three listed as critically endangered: B. asympeltata (Ecuador), B. pelargoniiflora (Cameroon and Equatorial Guinea), and B. salaziensis (Mauritius).The American Begonia Society (ABS) is a resource in species conservation, promoting interest, cultivar development, nomenclatural standardization, research and public education of begonias and has built a seed bank (Fuqua 2005; ABS website).
Because they accumulate free oxalic acid, a product of metabolic activity, in their leaves and petals, most begonias are sour to the taste.While some species are used as a substitute for rhubarb (e.g. Begonia rex) others are toxic, and some ornamental begonias are listed as potential household hazards (Wikipedia 2014; Kinghorn 2013).
Begonia is a genus of perennial flowering plants in the family Begoniaceae. The genus contains more than 2,000 different plant species. The Begonias are native to moist subtropical and tropical climates. Some species are commonly grown indoors as ornamental houseplants in cooler climates. In cooler climates some species are cultivated outside in summertime for their bright colorful flowers, which have sepals but no petals.
With 2,002 species, Begonia is one of the largest genera of flowering plants.[1][2] 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. 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 (unequal-sided).
Begonia brevirimosa
Begonia aconitifolia
A flowering begonia
Begonia cultivars come in many different colors, such as yellow
A begonia leaf
A pair of blossoms, male and female
A nautilus-leaf form of begonia
Begonia
Begonia leaf
Cracklin Rosie begonia
Cracklin Rosie begonia
Leaf of Begonia masoniana
The genus name Begonia was coined by Charles Plumier, a French patron of botany, and adopted by Linnaeus in 1753, to honor Michel Bégon, a former governor of the French colony of Saint-Domingue (now Haiti).
The following phylogenetic tree shows the relationships among sections of the genus Begonia.[3]
Begonia Yellow‑Flowering African Begonia (YFAB)Section Scutobegonia
Section Filicibegonia
Section Loasibegonia
Section Erminea
Fleshy‑Fruited African Begonia (FFAB)Section Quadrilobaria pro parte
Section Mezierea
Nerviplacentaria–Quadrilobaria Clade
Malagasy Begonia (MB)Section Tetraphila pro parte
Section Tetraphila pro parte
Section Baccabegonia
Section Squamibegonia
Section Tetraphila pro parte
Seasonally Dry Adapted African Begonia 1 (SDAAB 1)Section Sexalaria
Section Rostrobegonia
Neotropical Clade 1Section Gaerdtia
Section Latistigma
Section Tetrachia
Section Kollmannia
Begonia acetosa Clade
Section Donaldia
Section Stellandrae
Wagneria Clade
Core Pritzelia Clade
Asian Begonia Socotran Begonia (SB)Section Peltaugustia
Section Reichenheimia pro parte
Section Haagea
Section Reichenheimia pro parte
Asian Clade CSection Lauchea
Section Parvibegonia + Begonia smithiae
Section Diploclinium pro parte
Section Alicida
Section Diploclinium pro parte
Section Diploclinium pro parte
Section Diploclinium pro parte
Section Diploclinium pro parte
Section Diploclinium pro parte
Section Platycentrum
Asian Clade DSection Coelocentrum
Begonia amphioxus Clade
Section Ridleyella
Section Baryandra
Section Begonia olivacea
Section Jackia
Section Bracteibegonia
Ptermannia–Symbegonia Clade
Seasonally Dry Adapted African Begonia 2 (SDAAB 2)Section Augustia
Neotropical Clade 2 Neotropical Clade 2‑iiiSection Eupetalum pro parte
Section Eupetalum pro parte
Section Eupetalum pro parte
Begonia cremnophila Clade
Section Knesebeckia I + Section Barya
Section Australes
Section Knesebeckia III pro parte
Section Knesebeckia III pro parte
Section Knesebeckia II
Section Gobenia
Neotropical Clade 2‑iSection Quadriperigonia
Section Parietoplacentalia
Section Urniformia
Section Gireoudia
Neotropical Clade 2‑iiSection Astrothrix
Section Solananthera
Section Microtuberosa
Section Pereira
Section Trachelocarpus
Section Rossmannia
Section Pilderia
Section Ephemera
Section Ruizopavonia
Casparya–Semibegoniella Clade
Section Lepsia
Section Doratometra
Section Begonia
Begonia acutifolia Clade
Section Hydristyles
Section Cyathcnemis
Selected species:[4]
The different groups of begonias have different cultural 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.[5]
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.
The nomenclature of begonias can be very complex and confusing. The term 'picotee' refers to edging on the petals that is in contrast to the color of the main petal if the colors blend. If they do not, then the term 'marginata' is used, but sometimes these terms are used simultaneously.[6] 'Non-Stop' refers to a camellia tuberous hybrid that under certain conditions will bloom 'non-stop' all year round.
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 classifies begonias into several major groups:
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.
The following is a selection from about 70 species, varieties and cultivars which currently hold the Royal Horticultural Society's Award of Garden Merit:[7]
The cultivar 'Kimjongilia' is a floral emblem of North Korea.
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.[22]
Begonia is a genus of perennial flowering plants in the family Begoniaceae. The genus contains more than 2,000 different plant species. The Begonias are native to moist subtropical and tropical climates. Some species are commonly grown indoors as ornamental houseplants in cooler climates. In cooler climates some species are cultivated outside in summertime for their bright colorful flowers, which have sepals but no petals.
Pink flowering Begonia
