Iron Cross Begonia

Basic Information

Common Name: Iron Cross Begonia

Scientific Name: Begonia masoniana

Native Habitat: New Guinea

History / Discovery / Cultivator

Begonia masoniana, commonly known as the Iron Cross Begonia due to the distinctive, dark brown cross-shaped marking in the center of its textured, puckered leaves, is a fascinating and relatively recent addition to the world of cultivated begonias. Its discovery is intrinsically linked to the renowned plant collector and botanist Maurice Mason.

Maurice Mason, a Norfolk farmer with a deep passion for exotic flora, embarked on several plant-hunting expeditions, primarily to Southeast Asia, throughout the mid-20th century. It was during one of these expeditions, specifically to New Guinea in the early 1950s (some sources specify 1952), that he first encountered what would become Begonia masoniana. The exact circumstances of the discovery are somewhat anecdotal, adding to the mystique surrounding the plant. One prevailing account suggests that Mason discovered the Begonia growing on rocky outcrops in a remote region of the island. He was immediately captivated by the plant’s unique leaf structure and striking markings, unlike anything he had seen before.

Upon returning to his estate in Norfolk, England, Mason meticulously cultivated the newly acquired Begonia, propagating it and studying its growth habits. He recognized the horticultural potential of this unusual plant and began to share it with other enthusiasts. It’s important to note that the precise identification and classification of the species took some time. Initially, it was circulated under various provisional names.

The formal description and naming of Begonia masoniana occurred in 1955 by German botanist Ruth Ziesenhenne. She recognized it as a distinct species and honored Maurice Mason for his role in its discovery and introduction to cultivation by using the epithet “masoniana.”

The popularity of Begonia masoniana grew steadily in the following decades, largely due to its striking appearance and relatively easy cultivation as a houseplant. While not as ubiquitous as some other Begonia species, it remains a highly sought-after plant among collectors and enthusiasts, prized for its unique foliage and the intriguing story behind its discovery. The plant’s textured leaves make it a conversation starter and its distinct patterns stand out compared to more common houseplants.

The Iron Cross Begonia is still relatively rare in some regions, partly because of the challenges in propagation. However, its appeal continues to endure, ensuring its place as a botanical treasure discovered and popularized by the dedication and passion of Maurice Mason. The success of the plant in cultivation stands as a testament to both Mason’s keen eye for exceptional plants and to Ruth Ziesenhenne’s botanical expertise.

Plant Care Summary

Botanical Insights

Adaptations

The Iron Cross Begonia’s adaptations largely revolve around its native tropical environment. The puckered, textured surface of its leaves is believed to aid in water collection and reduce water loss in humid environments. The prominent brown “Iron Cross” marking may serve as camouflage or mimic the appearance of less palatable plants, deterring herbivores. As a plant that thrives in the dappled light beneath the canopy, the broad leaves are adapted for efficient light capture in shaded conditions. Finally, its sensitivity to cooler temperatures indicates an adaptation to consistently warm tropical climates.

Propagation Methods

Begonia masoniana can be propagated through several methods, the most common being leaf cuttings. To propagate via leaf cuttings, select a healthy leaf and cut it into sections, ensuring each section includes a vein. Place the leaf sections on a bed of moist sphagnum moss or well-draining potting mix, and cover with a humidity dome or plastic wrap. Keep the cuttings warm and humid, and new plantlets should emerge from the cut edges of the leaf within a few weeks. Stem cuttings can also be successful, though less common. Take a cutting with a few leaves and place it in water or directly into moist soil. Division of larger plants during repotting is another viable option. Seed propagation is possible but less common and requires specific conditions and fresh seeds.

Toxicology

The Iron Cross Begonia contains soluble calcium oxalates, which are toxic to both humans and pets, especially cats and dogs. If ingested, these oxalates can cause immediate and intense oral irritation, characterized by drooling, pawing at the mouth, and vomiting. In humans, ingestion can lead to a burning sensation in the mouth and throat, difficulty swallowing, and potentially nausea. While rarely life-threatening, it’s essential to keep this plant out of reach of children and pets. Contact with the sap may also cause skin irritation in sensitive individuals.

Common Problems

Pests:

• Mealybugs
• Spider mites
• Aphids

Diseases:

• Powdery mildew
• Root rot
• Botrytis blight

Other:

• Leaf yellowing: Often caused by overwatering or poor drainage.
• Browning leaf edges: Typically due to low humidity or inconsistent watering.
• Stunted growth: Can result from insufficient light or lack of nutrients.

Rarity & Value

Rarity:

The Iron Cross Begonia is considered relatively rare compared to more common Begonia varieties. Its slow growth rate and somewhat challenging propagation contribute to its limited availability. While not exceptionally difficult to care for, it requires specific conditions to thrive, which can deter some growers. It is no longer considered to be as exceptionally rare as it was when first discovered, but it is not a ubiquitous plant either.

Value:

The value of a Begonia masoniana specimen is influenced by several factors. Larger, more mature plants with well-developed “Iron Cross” markings generally command higher prices. The overall health and vigor of the plant are also crucial. Collector trends and the availability of the plant in a particular region can also impact its market value. The condition of the foliage greatly impacts its value. Plants with damaged or poor looking foliage are much less valuable.