IN THE GARDEN

By Doreen Trudel

There are still plenty of reasons to be outside in the garden but after the bulbs are in the ground, when impulsive nursery purchases have all found homes in the garden and the rain forces you inside you can begin collecting ideas for improvements and additions to the garden.

Hedging and privacy screening continues to be a popular topic among gardeners. I have previously written about mixed hedges and various evergreen shrubs which provide privacy but I haven’t discussed one of the fastest growing but misunderstood screening plants – bamboo. It will quickly provide a long lived, year round easy maintenance screen. It can also be used as either background or focal point in a large garden bed. Because it is so adaptable it blends well with shrubs, perennials and grasses in many garden styles.

Bamboo is a member of a subgroup of the grass family, Poaceae (Gramineae) consisting of approximately 1200 species. Culms (the stalks of bamboo commonly referred to as canes) grow from rhizomes. Photosynthesis takes place in the leaves converting minerals from the soil into nutrients used by the plant which are stored in the rhizomes. The rhizomes enlarge, more culms are produced and a bamboo grove is established.

The life cycle of bamboo consists of three parts; a very short seedling period, rhizome development which is most of the life span of the plant and lasts many years and finally the flowering stage which sometimes leads to the decline of that rhizome. Seeds are produced so if the plant dies after flowering new seedlings are ready to replace the parent plant and new culms may appear from existing rhizomes.

There are two main categories of bamboo, commonly referred to as running or clumping. The rhizomes of running bamboo such as Phyllostachys, Sasa, Shibataea, Chimonobambusa, Indocalamus, Pelio-blastus, Pseudosasa and Semiarundinaria quickly spread away from the parent plant and send up new culms forming large areas or groves of bamboo.

The rhizomes of clumping bamboo such as Bambusa, Fargesia, Otatea, Chusquea and Drepanostachyum grow a short distance before producing new culms forming clumps which gradually increase from the edges of the clump. Among the varieties that are particularly suited to our climate Fargesia murielae, F. nitida, Bambusa multiplex, B. oldhamii and Chusquea culeou are commonly available.

You can grow the running varieties surrounded by a barrier of metal, concrete or clay to keep the rhizomes contained but the roots are so strong that even a pond liner will not contain bamboo. Running bamboo varieties can also be grown in pots but they must be transplanted to bigger pots or root-pruned to prevent them from becoming pot-bound.
There are so many clumping varieties from which to choose I think it is safer to plant one of these and forget about barriers. If the clump of bamboo is getting too large simply cut into the outside rhizomes with a spade to remove the excess growth.

Contrary to common wisdom, bamboo does not like a wet site. Moist, well-drained, neutral to acid soil is ideal but bamboo will grow in all but totally wet or completely dry conditions in sun or light shade. Most bamboo rhizomes and roots grow within the top one and one half feet of soil so you do not need to prepare the soil below this depth unless your soil does not drain well. A top-dressing of compost or well-rotted manure will compensate for the missing nutrients in sandy soil. Water regularly during the first two years after planting during which time growth will be slower as the rhizomes establish themselves. Once established monitor the bamboo for water requirements but many bamboo varieties need supplemental watering only during the dry months.

Bamboo is relatively trouble-free. Too much or too little water seems to be the most common cause of its demise. Our cooler climate actually discourages most of the common pests such as aphids, scale, mealy bugs, mites and whitefly. Attacks by any of these insects are usually superficial and will not seriously harm the plant. Bamboo growing in our climate is not prone to disease.

For more information about specific bamboo varieties I recommend Ornamental Bamboos by David Crompton and the Sunset Western Garden Book. Some people consider bamboo to be over used but I think its colorful characteristics just have not been used creatively and the lovely sound emanating from the center of a bamboo grove is an added bonus.

The next meeting of the Point Roberts Garden Club will be on October 11 at 7 p.m. at the community center on Gulf Road. Have a happy and safe Canadian Thanksgiving.