Bambusa oldhamii

Giant Timber Bamboo
Poaceae (Gramineae)
Bamboo

BAMBUSA

Though some grow as tall as trees, all bamboos are actually grasses. Plants consist of woody stems (culms) that are divided into sections (internodes) by obvious joints (nodes). Upper nodes grow buds that develop into branches and leaves. Bamboos spread by underground stems (rhizomes) that, like the aboveground culms, are jointed and carry buds. Members of this genus, Bambusa, are all clumping bamboos—that is, their rhizomes grow just a few inches from the edges of the clump, then send up stems. Clumps expand continually but slowly.

Culms of all bamboos have already attained their maximum diameter when they emerge from the ground. In mature plants, new shoots usually reach their maximum height within 1 to 2 months. Culms of giant types may grow in length several feet a day. Don’t expect such growth the first year after transplanting, though.

Flowering of bamboos is one of the great mysteries of this unique plant. Most species flower periodically all over the world at the same time for a period of 2 to 7 years at intervals varying from 10 to 120 years, depending on species. Flowering generally weakens these plants, and although they may slowly recover, they often die. Very heavy feeding and watering may speed their recovery. Bamboo flowers are interesting but not usually decorative, resembling the seed heads of other grains.

Bambusa oldhamii

From south China and Taiwan, this densely foliaged clumping bamboo grows 15 to 25 ft. tall early on, but can eventually reach 20 to 55 ft.; stems are about 4 in. in diameter. The plant's erect clumps are good for big, dense screens—or use a single plant as an imposing vertical mass.