Yes, certain bamboo species exhibit purplish or black hues. While a vibrant, bright purple bamboo like some flowers does not naturally exist, various species develop deep, rich purplish-black culms (stems) as they mature, especially when exposed to sufficient sunlight.
Understanding Purple Bamboo
The concept of “purple bamboo” refers to bamboo culms that undergo a color transformation, typically from green to a darker shade of purple, reddish-brown, or black. This distinctive coloration is primarily observed on the culms, not the leaves, and its intensity can vary depending on the specific species, age of the culm, and environmental factors like sun exposure. The development of these darker hues is a natural process, occurring as the culm matures over one to three seasons.
New bamboo shoots emerge green, gradually developing their characteristic dark color over time. Culms may first appear mottled green and black before fully transitioning to their mature, darker shade. Sunlight plays a role in enhancing this pigmentation, leading to a richer, more pronounced color.
Common Purple Bamboo Varieties
Several bamboo species are known for their striking purplish or black culms. Phyllostachys nigra, commonly known as Black Bamboo, is one such species. Its culms emerge green and gradually turn a polished black or purplish-black over two to three years. This running bamboo can reach heights of 15 to 25 feet, with culms up to 2 inches in diameter.
Another variety is Gigantochloa atroviolacea, often called Java Black Bamboo or Tropical Black Bamboo. This species is a clumping bamboo, meaning it grows in dense clusters rather than spreading aggressively. Its culms begin as dark green and become jet black or purplish-black within six to twelve months, with the color intensifying in drier conditions. Gigantochloa atroviolacea can grow up to 30 feet tall with culms 1 to 2 inches in diameter. Some Bambusa textilis cultivars also develop purple or black culms, though their darkening process may take longer.
Growing Purple Bamboo
Cultivating bamboo varieties with colored culms involves care to encourage vibrant coloration and healthy growth. Sunlight is a factor, as full sun exposure promotes the deepest purplish or black hues. While some species like Phyllostachys nigra can tolerate partial shade, their color development might be less intense. Most bamboos thrive in well-draining, moist, and fertile soil, preferring a slightly acidic to neutral pH.
Consistent watering is necessary, especially for newly planted bamboo and during dry periods, to establish a robust root system. Deep watering less frequently is more effective than shallow daily watering. For clumping bamboos like Gigantochloa atroviolacea, water can be focused around the base, while running bamboos require saturation of a wider area. Applying a balanced fertilizer and mulching can further support growth and maintain soil moisture. If growing running bamboo, containment methods like root barriers are used to manage their spread.