Bamboo holds the world record for being the fastest growing plant. This is welcome news for the impatient gardeners among us – or is it? While bamboo provides the instant gratification of being a fast grower, some varieties of bamboo can become very invasive and grow out of control. Is black bamboo invasive though? Read on for the answer and learn how to care for black bamboo plants in the garden.
I. Appearance and Characteristics
Phyllostachys nigra, commonly known as black bamboo or purple bamboo (Chinese: 紫竹), is a species of bamboo, native to Hunan Province of China, and is widely cultivated elsewhere.
Growing up to 25 m (82 ft) tall by 30 cm (1 ft) broad, it forms clumps of slender arching canes which turn black after two or three seasons. The abundant lance-shaped leaves are 4–13 cm (2–5 in) long.
Numerous forms and cultivars are available for garden use. The species and the form P. nigra f. henonis have both gained the Royal Horticultural Society’s Award of Garden Merit. The form henonis is also known as Henon bamboo and as cultivar ‘Henon’.
Like many species of bamboo, black bamboo synchronizes its flowering, with flowering events happening every 40-120 years. According to one source, it has bloomed every 120 years “since records have been kept”. It is monocarpic, that is, after flowering, the plants die.
Henon bamboo flowers every 120 years and is predicted to flower in the 2020s. Since it is widely distributed in Japan, dieback of its stands may cause serious social and environmental problems. Moreover, Henon bamboo rarely sets fertile seeds, so it is not clear how this species has survived over long periods in Japan.
II. How to Grow and Care
Sunlight
Black bamboo is not overly picky when it comes to light conditions. It can be grown in anything from full sun to partial shade.
Temperature and Humidity
Considered one of the hardiest bamboo species out there, black bamboo can be grown in zones 7 to 10. Despite being a tropical plant, this bamboo variety can withstand temperatures down to 0 degrees Fahrenheit. This makes black bamboo a perfect choice for northern gardeners.
For those living in areas with harsh winters, black bamboo grown in containers can easily be brought indoors for the colder months. As for humidity, black bamboo is quite tolerant of varying conditions. However, if kept indoors, the occasional misting will ensure better growth and vitality.
Watering
Black bamboo loves water and will benefit most from a consistent watering schedule. Try to keep your soil moist, but never soggy.
For bamboo plants in a container, you will need to water more frequently. Depending on the humidity and temperature in your area, you may need to water these plants as often as every other day.
Soil
Black bamboo loves nutrient-rich soil. Moist, loamy, well-draining types are ideal for optimum growth. A mix of sand, clay, and silt is a great combination, but black bamboo can adapt to many soil conditions as long as it is well-draining.
To help keep your soil a healthy balance of moist and well-draining, try adding a layer of mulch around your bamboo.
Fertilizing
To promote healthy growth, you might choose to fertilize black bamboo for a boost of additional nutrients. Choose a fertilizer that is high in nitrogen for the best results; this type of fertilizer is typically best for grasses. Apply fertilizer in the late spring and again in the middle of the growing season.
Pruning
Bamboo is known to be a fast-growing plant, which adds to its appeal as a natural privacy barrier. However, to keep the height of your bamboo in check, you should plan to occasionally prune the plant to your desired height.
Pruning bamboo to control growth should be done in the spring. The nodes of the plant provide an easy visual cue on where to cut back the height of each stalk. Cut each stalk just above a node.
In addition, curb unwanted growth of in-ground black bamboo plants by cutting new shoots that sprout from the rhizomes to ground level. Keep in mind that this will check the growth of this plant, but it is a prolific spreader once planted directly in the ground and you may not be able to control its growth simply by cutting back new growth.
Propagation
Propagating bamboo is simple and best done by division. It is ideal to divide bamboo plants in the late winter or early spring.
- Water the bamboo well the day before you plan to divide it.
- Before dividing, cut off the top 2/3 of the culm.
- Using a sharp spade, dig up the section you would like to divide. You may need a saw to cut through the thick roots.
- From here, you can keep the clump large or divide it into smaller sections of 3 or 4 culms each.
- Plant each section in a hole twice as wide as the root ball.
- Mix in compost or other fertilizer and fill in the area.
- Water thoroughly.
Potting and Repotting
Black bamboo can easily be grown in containers, which is a perfect choice for those with smaller yards or who want to keep it inside. When choosing a container, try to find one that is short, wide, and bottom-heavy. Adding rocks to the bottom of the container can help with this. Because bamboo grows to be so tall, a lighter, taller pot can easily get blown over.
Since black bamboo is a running bamboo and a rapid grower, it may outgrow its pot quicker than other species. You will need to repot once your bamboo is root-bound. Potted bamboo will need more water than plants in the ground, so be sure to keep tabs on your soil moisture. Place your pot in a sunny, wind-sheltered area and enjoy it’s striking looks and green foliage.
III. Uses and Benefits
It is used for lumber (timber), food, and musical instruments, among other things, in areas of China where it is native and also worldwide.
IV. Harvesting and Storage
Bamboo shoots make an interesting and fun addition to vegetable stir-fries and are often used in Asian cuisine. To harvest the young sprouts, wait until they are a few inches tall. Try to harvest while they are 6 inches or less for the best flavor.
Using a sharp knife, cut the shoot at ground level. Be sure to harvest plants sustainably and responsibly, making sure not to strip the plant of all of its new growth. When you are ready to prepare your harvest, cut the shoots in half length-wise and remove the hard outer sheath. Then, cut them to the desired thickness and boil or fry them.
