Begonia rex

Begonia rex, the king begonia, is a species of flowering plant in the family Begoniaceae. It is found from Arunachal Pradesh to southeast China, and has been introduced to Bangladesh, Cuba, and Hispaniola.^[1][2] It is a parent to over 500 cultivars in the Begonia Rex Cultorum Group of houseplants.^[3] Other parents in the multitude of crosses made during the creation of the Group include Begonia annulata, B. cathayana, B. decora, B. diadema, B. dregei, B. grandis, B. hatacoa, B. palmata, and B. xanthina.^[3]

Begonia rex
Begonia rex 'Red Tango' cultivar
Putative variety Begonia rex var. imperator by Adam Gatternicht
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Cucurbitales
Family:	Begoniaceae
Genus:	Begonia
Species:	B. rex
Binomial name
Begonia rex Putz.
Synonyms[1]
Platycentrum rex (Putz.) Seem. 1860 Begonia dominiana Veitch ex J.Dix 1859 Begonia marginata T.Moore 1860 Begonia picturata Hend. ex Bosse 1861 Begonia rex var. grandis E.J.Lowe & W.Howard 1859 Begonia rex var. leopardina T.Moore 1860 Begonia rex var. nebulosa E.J.Lowe & W.Howard 1860

The following cultivars in the Begonia Rex Cultorum Group have gained the Royal Horticultural Society's Award of Garden Merit: 'Benitochiba', 'Carolina Moon', 'China Curl', 'Curly Fireflush', 'David Blais', 'Dewdrop', 'Emerald Beauty', 'Escargot', 'Fireworks', 'Green Gold', 'Helen Lewis', 'Hilo Holiday', 'Ironstone', 'Martin Johnson', 'Midnight Magic', 'Mikado', 'Namur', 'Orient', 'Pink Champagne', 'Princess of Hanover', 'Red Robin', 'Regal Minuet', 'Rocheart', 'Roi de Roses', 'Sal's Comet', 'Sea Serpent', 'Silver Cloud', 'Silver King', and 'Silver Queen'.^[4]

These plants are noted for their dark leaves with prominent silvery grey bands. When this species was introduced into cultivation, it became popular as a houseplant. Hybrids began to appear with varying leaf patterns as Rex begonias hybridize quite freely.^[5]

Light

Rex begonias do well in bright, indirect light. Foliage of these plants could burn when plants are exposed to excessive direct sunlight. The ideal light intensity for most Rex begonia varieties is 1,500 to 2,200 foot-candles.^[6]