Rex Begonia

Basic Information

Common Name: Rex Begonia

Scientific Name: Begonia rex

Native Habitat: Northeast India, China, Vietnam

History / Discovery / Cultivator

Begonia rex, with its flamboyant and diverse foliage, boasts a history interwoven with exploration, cultivation, and enduring popularity. The species was first discovered in Assam, Northeast India, in 1856 by plant hunter William Griffith. Griffith, an employee of the East India Company, was collecting botanical specimens when he encountered the strikingly patterned foliage of what would become known as Begonia rex. He sent specimens back to England, where they captivated botanists and horticulturists.

The scientific name, Begonia rex, directly translates to “King Begonia,” a testament to the plant’s regal appearance. The “rex” epithet reflects the large size, bold patterns, and vibrant colors that differentiate it from other Begonia species. Early botanists recognized its unique qualities and the potential for hybridization and cultivation.

It wasn’t long before breeders began experimenting with Begonia rex, crossbreeding it with other Begonia species to create a dazzling array of cultivars. The late 19th and early 20th centuries saw a surge in the development of new Rex Begonia varieties, each with its own distinctive leaf shape, color combination, and texture. Hybridizers focused on enhancing desirable traits such as leaf size, color intensity, and overall plant vigor.

Among the influential cultivators and breeders of Rex Begonias was Anton Hoog of Holland, who, in the early 20th century, introduced many significant cultivars that remain popular today. His work contributed significantly to the plant’s widespread availability and enduring appeal. Other notable figures in the development of Rex Begonias include the French hybridizer Victor Lemoine, whose work in the late 19th century further expanded the range of available varieties.

The Rex Begonia quickly gained popularity as a houseplant, prized for its ornamental foliage and relatively easy care under indoor conditions. Its ability to thrive in bright, indirect light and tolerate moderate humidity made it well-suited to the home environment. Furthermore, its diverse range of leaf colors, including shades of green, silver, red, purple, pink, and brown, allowed for endless possibilities in interior design.

Today, Begonia rex and its many cultivars continue to be beloved by plant enthusiasts worldwide. Its history is a testament to the enduring power of plant exploration and the transformative impact of selective breeding. From its humble beginnings in the forests of Northeast India, the Rex Begonia has evolved into a global icon of horticultural beauty. Its vibrant foliage and relatively easy care make it a popular choice for both novice and experienced plant collectors, ensuring its continued presence in homes and gardens for generations to come. The ongoing development of new and exciting cultivars ensures the Rex Begonia remains a dynamic and captivating addition to the world of ornamental plants.

Plant Care Summary

Botanical Insights

Adaptations

Rex Begonias have evolved several interesting adaptations. Their large, often asymmetrically shaped leaves maximize light capture in the dappled shade of their native forest floors. The varied leaf patterns and colors may serve as camouflage or as a visual deterrent to herbivores. Some Rex Begonias develop rhizomes, which are modified stems that grow horizontally along the surface or just below the soil. These rhizomes allow the plant to spread vegetatively and store nutrients, enabling it to survive periods of drought or nutrient scarcity. As houseplants, their tolerance for moderate shade and relatively low maintenance requirements have contributed to their popularity.

Propagation Methods

Rex Begonias can be propagated through several methods:

• Leaf Cuttings: This is perhaps the most common and effective method. A single leaf can be cut into sections, with each section placed on a moist growing medium.
• Rhizome Cuttings: If the plant has a rhizome, sections can be cut and replanted.
• Stem Cuttings: While less common, stem cuttings can also be used, especially if the plant has a trailing growth habit.
• Division: Mature plants can be divided at the root ball, ensuring each division has sufficient roots and leaves.

Toxicology

Rex Begonias contain soluble calcium oxalates, which are toxic to both humans and pets if ingested. When consumed, these oxalates can cause oral irritation, excessive salivation, vomiting, and difficulty swallowing. In severe cases, ingestion can lead to kidney damage. Pets, particularly cats and dogs, are more susceptible to the toxic effects due to their smaller size. It is crucial to keep Rex Begonias out of reach of children and pets to prevent accidental ingestion. If ingestion is suspected, immediate veterinary or medical attention is recommended.

Common Problems

Pests:

• Mealybugs
• Spider Mites
• Aphids

Diseases:

• Powdery Mildew
• Root Rot
• Botrytis Blight

Other:

• Leaf Yellowing: Often caused by overwatering or nutrient deficiency.
• Browning Tips: Usually due to low humidity or inconsistent watering.
• Leaf Drop: Can be caused by temperature stress, underwatering or overwatering.

Rarity & Value

Rarity:

While some Rex Begonia cultivars are widely available, certain varieties, particularly those with unique variegation patterns, unusual leaf shapes, or limited production, can be considered relatively rare. Older, heirloom varieties may also be harder to find. Slow growth and the difficulty of reliably propagating some cultivars contribute to their scarcity.

Value:

The value of a Rex Begonia specimen is affected by several factors. Size and maturity play a role, with larger, more established plants commanding higher prices. Variegation quality and stability are crucial; highly contrasted, stable variegation patterns increase value. Rare or unique cultivars are generally more valuable. Current collector trends and the provenance (history of the plant) can also influence the price, especially for specimens with a documented history of award-winning or historically significant parentage.