Begonia ‘Black Mamba’ Rex Begonia

Begonia ‘Black Mamba’ (also sold as ‘Black Mambo’ or ‘Dark Mambo’) is a striking foliage begonia prized for its deep, almost black leaves. Broad, slightly ruffled blades show plum, blue, or red undertones depending on the light, giving this plant a dramatic, high‑contrast presence in any collection. It stays relatively compact and shrubby, making it ideal for shelves, desk corners, and plant cabinets where you want one small plant to anchor the whole display.
This cultivar is a rhizomatous begonia, growing from thick horizontal rhizomes rather than tall canes. Like most specialty begonias, ‘Black Mamba’ rewards consistent conditions: bright, indirect light, a chunky well‑draining mix, and moderate to high humidity. In the right spot, it responds with rich color, lush foliage, and a dense silhouette that plays beautifully with softer greens and variegates.
Features
• Near‑black, velvety foliage with subtle iridescent undertones
• Compact, shrubby growth habit from underground rhizomes
• Excellent for plant shelves, cabinets, and bright terrariums
• A standout specimen for collectors who love dark, dramatic leaves
Size
• Pot size: 4” nursery pot
• Typical indoor size: about 12–16” tall and wide with good care
Light
• Best in bright, indirect light to maintain color and healthy growth
• Avoid hot afternoon sun, which can scorch leaves
• Can sit a bit back from the window, but will look its best with consistent filtered brightness
Water & soil
• Keep soil evenly moist but never waterlogged
• Allow the top layer of the mix to dry slightly before watering again
• Use a light, airy, organic mix with added perlite/pumice for drainage
• Overwatering is the most common issue; this begonia stores moisture in its rhizomes and leaves, so it prefers “slightly dry” over “soggy”
Humidity & temperature
• Prefers humidity above 50%
• Thrives in plant cabinets, bright bathrooms, or near a humidifier
• Ideal temperature range: roughly 65–75°F (18–24°C)
• Protect from cold drafts and sudden temperature swings
Pet information
• Begonias are considered toxic if ingested by pets or humans
• Keep out of reach of curious cats, dogs, and small children
What you’ll receive
You’ll receive a well‑rooted Begonia ‘Black Mamba’ in a nursery pot, similar in size and quality to the plant shown in the photos. Natural variation in leaf shape and depth of color is expected and part of what makes this cultivar unique.