There are over a thousand different varieties of Bamboo, each with its unique growing habit, height, texture, and color. With so many varieties, you are sure to find one or two that will be a terrific addition to the garden. From sun to shade and from groundcover to a skyscraper, there is a variety for just about any space.
Bamboo is some of the fastest-growing plants in the world, reaching maturity typically in five to six years. This makes for quick, relatively inexpensive, and lush privacy screens. New shoots emerge in the spring typically between April and June and reach their full height in two to three months! They grow slightly larger than the previous years’ canes. Bamboo is also pest-resistant, incredibly easy to grow, and is great for erosion control. They also create a habitat for wildlife and are usually non-allergenic since they don’t flower for anywhere from 80-130 years. The new shoots of some varieties can also be edible if steamed or sautéed.
So, what’s the problem? Because it can be so easy to grow, some varieties can quickly become invasive. Think: Bamboo growing into your neighbor’s backyard (generally not a happy neighbor). Once Bamboo is established it can be a nightmare to try to remove, and so if you like to rearrange your garden every few years, this may not be the plant for you. That being said, a little knowledge goes a long way in selecting, maintaining, and enjoying Bamboo.
The most common type of running Bamboo in our area is Phyllostachys (Fye-LO-stoc-ees). This is typically what you think of when you envision lush, tropical Bamboo forests. They tend to be fast-spreading and hardy, able to withstand heat, cold and drought once established. The culms (stems) come in a variety of colors from yellow, green and black.
Typically, mid-sized Phyllostachys varieties are 15-30’ tall and have culms that are 1-2” in diameter. The most common varieties are Phyllostachys nigra with a black culm, Phyllostachys aurea with a yellow culm, and Phyllostachys aureosulcata. There is also big timber Bamboo, with some varieties growing well over 40 -50 feet tall and 5-6 inches in diameter. They can quickly form massive groves and need space to run, so give them at least a 25’x25’ area.
Just because it’s a runner doesn’t mean you shouldn’t consider it. With the proper planning and maintenance, you can have a beautiful screen or hedge in no time. For dense screening, you want to plant the Bamboo 3-5’ apart. Make sure to either use a Bamboo barrier made of HDPE (high-density polyethylene), typically at least 60 mils by 30” deep, or plan on installing a sand trench 8-10” deep and root pruning twice a year. It is recommended to check in the late summer and fall to see if rhizomes have crossed the trench, and if so, cut them off.
Hardy clumping Bamboo
For most gardens, you will want to go with clumping Bamboo. They tend to better behave as they have a non-invasive rhizome structure that grows outward in a circular formation anywhere from 4- 10” inches a year. They usually are somewhere between 8-25 feet high, growing 1-2’ taller each year depending on the variety. The most commonly used variety is Fargesia (Far-JEEZ-ee-ah) which tends to be shade-loving and cold-hardy. Some tolerate a fair amount of sun but do need afternoon shade to stay attractive. A few varieties can also lose some leaves in the fall but won’t become completely bare. The most common varieties for the Pacific Northwest, which also happen to be the most sun tolerant, are Fargesia robusta ‘Campbell’, Fargesia sp. ‘Rufa’, Fargesia sp. ‘Scabrida’.
With clumping Bamboo, you want to make sure to root prune every two years to keep them from spreading.
Ground cover Bamboo
Pretty much any Bamboo that stays under 6’ is considered a groundcover. Great for erosion control and often fast-growing, some varieties may need some form of barrier control to keep them from taking over.
Planting Bamboo in containers
Bamboo planted in containers takes more care and maintenance than those planted in the ground. This is because they tend to be more exposed to heat and cold and because they have a more confined space to live in. Make sure to water at least 3-5 times a week during summer and possibly more if the Bamboo doesn’t like the hot sun. Make sure the container will allow for adequate drainage but keep in mind those rhizomes are experts at finding any hole and escaping! If your Bamboo is over 15’ you may want to consider guying them so that they don’t fall over in a high wind. Also, don’t expect it to grow to the height advertised as most Bamboo tend to only grow to about half their stated size. Most will tend to be transplanted after 6-8 years in a container and may die if not given more room. If you root prune your Bamboo, that may extend their longevity along with proper care and maintenance.
A word about containers. Make sure containers are a good size, typically at least 2’ wide and tall to provide enough space for roots. Also, take into account what the container is made of. Some metal containers will conduct the winter cold and possibly freeze your Bamboo, so cedar or other materials that are insulated tend to work better. If you are planning on transplanting, keep in mind that if there are any gaps or grooves in the containers, such as in the metal cattle troughs, it will be nearly impossible to get the Bamboo back out.
Care and maintenance of Bamboo
Pruning is an important part of maintaining healthy Bamboo. Make sure not to prune until after late summer when it is done producing new shoots and they have matured. You’ll want to prune any dead or weak culms by cutting them horizontally at the ground level. Thinning every three years or so is important to allow adequate airflow through the plant, but never cut more than 1/3 of the Bamboo out at any time. Once your Bamboo has reached the desired height, it can be topped by cutting just above the node. This will result in new foliage and a more dense and lush Bamboo.
Since Bamboo is a grass, it loves to be fertilized during the early spring and summer. Typically, applying a layer of 3-5″ of compost, or compost manure mix, will encourage rhizomes growth and help retain soil moisture in the spring. An application of lawn fertilizer high in nitrogen can also give it a boost.
Bamboo can be a bit messy, as they will lose some of their leaves throughout the year but especially in the spring which is their autumn. This is a great mulch and can be left on the ground. However, if you like to keep a tidier looking garden, then you will have some clean-up to do.
Remember to keep an eye out late summer and fall for rhizomes that are trying to escape, and cut them back before they can get established. If you happen to forget and all of a sudden have a lot more Bamboo than desired, then you may be in for a fight. Cut back the culms to the ground and mow down any tender new shoots. Repeat as new shoots emerge. With this method, you are trying to exhaust the energy stores in the rhizomes. The other option is to cut the culms down and then try to dig up the rhizomes making sure not to leave any pieces that could regrow. Wetting the soil will make it easier to dig the root ball out. Depending on the extent of the eradication, you may want to get a stump grinder to remove thick rhizome areas just make sure to get as much of the roots out of the soil or the Bamboo will regrow.
With a little knowledge and advanced planning, Bamboo can be a thrilling addition to the garden. My favorite local resource if you want a bit more help in selecting the right Bamboo or want to see some beautiful specimens up close would be to visit Bamboo Gardens in North Plains. This is a great spot to fully experience the variety, majesty, and beauty of Bamboo. Their website is also a great resource http://www.Bamboogarden.com/