Chimonobambusa quadrangularis

• Square Bamboo

Seed - surface sow as soon as it is ripe in a greenhouse at about 20°c. Do not allow the compost to dry out. Germination usually takes place fairly quickly so long as the seed is of good quality, though it can take 3 - 6 months. Grow on in a lightly shaded place in the greenhouse until large enough to plant out. Seed is rarely available.

Division in spring as new growth commences. Take divisions with at least three canes in the clump, trying to cause as little root disturbance to the main plant as possible. Grow them on in light shade in a greenhouse in pots of a high fertility sandy medium. Mist the foliage regularly until plants are established. Plant them out into their permanent positions when a good root system has developed, which can take a year or more^[2]. Basal cane cuttings.

Rhizome cuttings.

Prefers a good loamy soil. Succeeds in most soils so long as they do not dry out. Dislikes drought. Prefers a position sheltered from cold north and east winds.

Plants are only reliably hardy in the mildest areas of Britain. Another report says that the plants are generally hardy, although severe winters may damage the leaves the plant itself can withstand temperatures down to about -15°c^[2]. The square bamboo is cultivated for its edible stems in China and Japan. This species is notably resistant to honey fungus^[2]. Plants only flower at intervals of many years. When they do come into flower most of the plants energies are directed into producing seed and consequently the plant is severely weakened. They sometimes die after flowering, but if left alone they will usually recover though they will look very poorly for a few years. If fed with artificial NPK fertilizers at this time the plants are more likely to die^[3].

The rootstock is running but it does not produce many new shoots and is not overly invasive^[1]. The plant is rampant in its native range and other warm temperate areas, but it does not spread much in colder areas such as Britain^[2]. The shoots are wide spaced and are produced from late May. Canes can be snapped off the plant. A plant at Trebah gardens in Cornwall had new shoots 3 metres long in mid-April 1995[K].