Begonia maculata


Begonia maculata, the polka dot begonia, is a species of begonia native to southeast Brazil. It grows naturally in the understory of the Atlantic rainforest, with occurrences confirmed in the Brazilian states of Espírito Santo and Rio de Janeiro. It has been introduced into Mexico, Cuba, the Dominican Republic, and Argentina.
Begonia maculata has olive drab colored oblong leaves with silver dots. The undersides of the leaves are red-purple. The plant grows white or pink flowers in clusters with yellow centers on a single stem.

History

B. maculata was first documented by botanists based on a specimen found on the mountain Corcovado in central Rio de Janeiro. Giuseppe Raddi named and described the species in 1820. It's thought B. maculata is one of the 4000 specimens he acquired from a 7-month trip to Brazil in 1817.
Before the twenty-first century, this plant was commonly called trout begonia, fish begonia, and sometimes clown begonia. It wasn't until polka became popular in the mid-1800s that B. maculata and another popular houseplant, Hypoestes phyllostachya started being referred to as polka dot plants.

Plant Physiology

The white/silver spots on the leaves are caused by air trapped the epidermis, creating an effect known as blister variegation, or air space variegation. One theory on the evolutionary biology of these spots is that they mimic the appearance of butterfly eggs. Another possibility is these spots mimic pest damage from leaf miners.

Horticulture

B. maculata is a perennially popular houseplant. As early as 1871, the California Horticulturist described B. maculata as "a very desirable variety", and as recently as 2023, #begoniamaculata was the second most popular species-specific begonia hashtag on Instagram.

Propagation

The best conditions for propagating are bright, indirect light and water poured just below the surface of the soil anytime it seems dry to the touch. Use filtered water or rainfall, it requires less water but more often than other tropical plants.