The Bamboo Garden at Northern California’s Foothill College
I’ll admit, I’m not a huge fan of bamboo, especially the kind that advances a foot a day and needs to be dug out with a tractor. But I was pleasantly surprised this week to have my views suddenly upended. It all started with some aqua stems I spied growing in my sister-in-law’s garden.
A CALIFORNIA JAPANESE GARDEN
Nestled in the hills of Northern California, my sister-in-law’s garden was created by a Japanese landscape designer. Like wine, it took shape over years, gradually achieving a fine balance of appearance and aroma. The zen-like retreat takes its cues from nature. Composed of a network of narrow earthen paths, it weaves the visitor through interesting foliage, sculpted branches and sweet-scented blooms. And in January, the garden is awash with camellias.
Along one side of the garden there is a giant hedge of bamboo whose arching, delicate green foliage flutters softly overhead. However, it’s the kind that likes to spread, which normally dissuades people like me from planting it. But new this year, tucked into a quiet corner of the barrier was a species I had never seen before. In contrast to the privacy screen, it was smaller and had striking blue-green stems. What is more, it was the slow-spreading, clumping kind.
My sister-in-law’s clumping, aqua blue bamboo
Clearly bamboo had more to offer than I had previously imagined.
THE FOOTHILL COLLEGE BAMBOO GARDEN
Following my visit, my girlfriend suggested we tour a bamboo garden near her home in California’s Los Altos Hills. Located on the campus of Foothill College, the two-acre garden covers a slope just below the Japanese Cultural Center. To be sure, the aqua-stemmed bamboo had peaked my interest. So, curious to see what other varieties I might discover, I agreed to go.
Foothill College’s Japanese Cultural Center
The Bamboo Garden at Foothill College is first and foremost a demonstration garden. Created in 1989, it today showcases around 70 different bamboo varieties. Ranging in size from groundcovers to specimens over a hundred feet tall, the plants are a tapestry of airy leaf forms held aloft by bright-colored stems. Moreover, many are species not commonly found in the United States.
Pathway through Foothill College Bamboo Garden
Aside from its educational value (the different varieties are being studied for their adaptability to the San Francisco area), a visit to the garden is a multi-layered experience. Similarly to my sister-in-law’s, narrow paths loop back and forth across the slope, offering close-up views of the many exotic species.
WHAT KIND OF PLANT IS BAMBOO?
Bamboo is classified as a woody perennial grass plant. In other words, its stems don’t die back in winter but instead increase in size with each growing season. Part of the grass family (Poaceae), bamboo includes over 91 genera and around 1400 known species. Woody bamboo is most commonly found in tropical to subtropical or moderate climates, with most species hailing from East and Southeast Asia. However, a few species are native to the southern United States.
Bamboo is one of the fasted growing plants in the world.
Giant timber bamboo
ANATOMY OF A CULM
One of the most striking things about bamboo is its cylindrical stems, called culms. These unusual ‘trunks’ can range in size from 1 mm to 30 cm (approximately 12″) in diameter. Typically hollow, the culm segments begin and end with a solid joint called a node. A pair of rings protects each node, in a formation known as ‘swelling’.
Most of us are familiar with the typical bamboo culm shape. Ringed nodes alternate with smooth segments (called internodes) that vary in length, number and shape depending on the variety. Not only do branches and leaves sprout from these nodes, but they each have culm-like nodes and internodes, too.
Culms of Phyllostachys vivax, one of the largest bamboos growing in the Pacific Northwest
Meanwhile underground, the bamboo root system also looks like a culm. But in this case, it’s on its side. Instead of branches and leaves, however, the rhizome produces roots and shoots at the nodes. Eventually these burst through the surface to form more culms. And this is what is referred to as running bamboo.
Indocalamus longiauritus, a small-sized running bamboo native to China
Bamboo is shallow-rooted with most of its growth taking place between late summer and early fall. Typically, most root systems do not extend further than 20 inches below the soil surface.
THE DIFFERENCE BETWEEN RUNNING AND CLUMPING BAMBOO
Unlike running bamboo, which grows horizontally, clumping bamboo has rhizomes that grow upwards before developing into a new culm. As a result, the plant tends to expand more slowly around the perimeter, giving it a ‘clumping’ habit.
Bambusa toldoides, also known as Punting Pole Bamboo, is a tall, clumping variety
SOME SPECIES TAKE A CENTURY TO FLOWER
Generally, bamboos aren’t known for their flowers; yet flowering plays an essential role in perpetuating each species. Some varieties flower continuously year after year in one to two month intervals. Others bloom only sporadically. But, the majority of woody bamboos flower once every 20 to 120 years.
Sadly, most species die soon after flowering. Scientists hypothesize that this allows the new seedlings to reap all the benefits of water, sunshine and nutrients that might otherwise be consumed by the mother.
HERE’S A REALLY COOL FACT: Many bamboo species exhibit what is called gregarious flowering, meaning that when they flower, they do so at the same time all over the world. And they bloom simultaneously, regardless of climate or geography! While the reason for this timed flowering is unknown, some scientists believe that bamboo cells may contain a genetic alarm clock that wakes them up at certain time periods that are predetermined.
SEVEN BAMBOOS THAT STAND OUT FROM THE CROWD
Intrigued by the possibilities? I am. Here are some beautiful bamboo species I spied at the Foothill College Bamboo Garden. For a complete list of species that can be found in the Foothill Garden, click here for the Foothill College site.
Phyllostachys nigra or Black Bamboo was the first species to be planted at Foothill College. Growing to about 16 feet tall, its slender, jet-black culms add a refined look to the garden. Indeed, Nigra is one of the most popular ornamental bamboos in the world.
Although the species is generally not considered invasive, growers recommend containing it with some type of rhizome barrier.
Bambusa chungii, also known as White Bamboo, makes a stunning statement perched on the Foothill Garden’s slope. The variety tops out at around 40 feet tall with culms measuring around two inches. The species’ dense form make it a great privacy hedge. And its clumping habit makes it easy to maintain as a specimen. A smaller version is called ‘Barbie.’
CHINESE TEMPLE BAMBOO
Sinobambusa tootsik ‘Albostriata’, also known as Variegated Chinese Temple Bamboo, is a running form that can be aggressive. However, its yellow and white striped leaves can do a lot to brighten a dark corner. Albostriata grows 15 to 20 feet tall with 1-inch diameter culms. It can also be controlled by a rhizome barrier.
Sinobambusa tootsik ‘Albostriata’
Native to southern Brazil, Chusquea mimosa is a clumping bamboo with arching stems. In my view, it resembles a Japanese maple with its clouds of small, lacy leaves. Generally, the species prefers part shade, but when grown in full sun its culms turn a shiny, dark red. It grows to about 45 feet high.
Native to Japan, Pseudosasa owaterii is one of the smallest known running bamboos. Reaching a maximum height of around 24″, it makes a delicate-looking groundcover.
MEXICAN WEEPING BAMBOO
Otatea acuminata aztecorum, or Mexican Weeping Bamboo, is a relatively rare species featuring very narrow leaves and a weeping form. A clumping variety, it is fast growing, eventually reaching a height of 12 to 15 feet.
Otatea acuminata aztecorum
GIANT TIMBER BAMBOO
Bambusa oldhamii is the most commonly grown species in the United States. Its dense evergreen foliage and impressive height (sometimes reaching 65 feet or more) make it a great choice for screening out your neighbor. Even better, it has a clumping habit and is non-invasive, making it a low maintenance choice for the homeowner.
Bambusa oldhamii is the most commonly grown species in the U.S.
Want to learn more? Check out Bamboo Botanicals’ information-packed site to see what cultivars might be suitable for your area. (This is also the source of my sister-in-law’s aqua cultivar.) Happy planting!