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Bamboos

Bamboos add a lush, jungly feel to any garden. Their evergreen leaves and beautiful canes combine to create a permanently exotic presence. They are also immensely versatile plants and can be used in a wide number of ways.

Bamboos can be used as single, ornamental specimens to liven up a dull corner of the garden or create interest in boring beds and borders. They are an essential ingredient of Japanese-style gardens, and make excellent screening plants for blotting out unsightly views or nosy neighbours. Planted between garden and roadside, they can help to mask the sound of noisy traffic.

They can be grown as informal hedges, coping well with light clipping. They are also a good choice for play areas in the garden because they can take a fair amount of rough treatment from rampaging children. Since they harmonize well with water, they look especially effective planted near streams or ponds. If you’re lucky enough to own a lake, large sweeps of bamboo planted along the edge make a fine sight. And, although bamboos are not good at coping with very windy, exposed positions, if they’re planted where light breezes can swish through them, the rustling sound is very soothing.

The idea of introducing bamboos to gardening schemes fills some people with horror, as they imagine wild, invasive plants taking over every corner, ripping up ponds and patios in their wake. Although some of the fast-growing tropical species have the potential for doing this, most bamboos behave in a much more restrained and dignified manner. In fact, many of the bamboos in this chapter stay in a nice tight clump even after a couple of decades.

Most bamboos are not invasive plants, but well behaved and dignified.

All of the bamboos featured here are fully hardy down to -20°C (-4°F), so there is a good choice of bamboo for even the coldest garden, ranging from the lofty heights of Semiarundinariafastuosa to the delicate form of Pleioblastus variegata. These plants have been chosen for their suitability for average temperate gardens, their ornamental qualities and ease of cultivation. There is also a good chance that specialist nurseries will stock them.

Choose a decent-sized plant for transplanting into the garden. Seedlings are slow to get started, and it can take around five years for a clump to become noticeable. Bamboos prefer a sunny spot, although most will tolerate some shade. For really shady spots, choose Pseudosasa japonica or Sasa palmata nebulosa, which are the least fussy to cultivate.

All bamboos look much better planted away from strong winds. Permanently breezy conditions won’t kill them, but the wind can scorch the leaf edges, leaving them brown and crispy. Plants look much greener and healthier in a sheltered spot. An exception to this is the robust Pseudosasa japonica, which can take an astonishing amount of battering from seasonal storms.

Bamboos are very thirsty plants and need permanent access to irrigation. However, they will not stand very waterlogged conditions, so good drainage is important. Pools of water stagnating around the roots will lead to rotting. The best examples of green and healthy bamboos with enormous canes are always to be found in gardens that have a high water table or alongside rivers or streams. In these positions, water is constantly available for them to help themselves whenever it’s required.

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Sasa palmata ‘Nebulosa’ has the largest leaves of any hardy bamboo.

With this in mind, growing bamboos in pots is a very bad idea. If they dry out, they die – it’s as simple as that. Once they reach that brown, parched look, you’ve had it. Just think how a lawn looks after a hot dry summer. Bamboo reacts in the same way. Recovery from a brown, crisp specimen takes such a long time that the best thing to do is dispose of it and start again, as any new growth that might occur will have to regenerate from the old root system. If growing in a container is unavoidable, choose a massive pot and install an automatic irrigation system.

Bamboos are also greedy plants and appreciate lavish quantities of well-rotted manure or a blood, fish and bone mix applied during spring and early summer. Never apply seaweed or seaweed extract – the salt in this can kill bamboos. The only other maintenance required is to remove any old, brown leaves and to keep a lookout for aphids. These horrid creatures enjoy feeding on the new shoots during early summer. If not dealt with, they excrete a sticky substance, politely referred to as honeydew. This honeydew can speedily turn black from sooty mould, giving an unsightly appearance to the plant.

Bamboos grown as a hedge or screen can be clipped lightly with shears along the top of the clump after the main growing season, which lasts from spring through to early summer. If a mature bamboo has grown taller than required, use secateurs to cut through any woody canes.

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New canes of Phyltostachys aureosutcata ‘Aureocaulis’.

New canes emerge from the ground during each new season. The width of these new canes remains the same throughout the bamboo’s life; small ones do not become fatter with age. Therefore, if you spot small, skinny canes, it would be a good idea to chop them off at ground level as soon as they appear, so that the plant can put all its energies into the larger ones. Each year, bamboos produce canes that are generally slightly fatter and taller than the previous year. The really huge canes found on bamboos are the result of two things: copious amounts of water and age. A really large clump of tall canes with a good circumference could be at least thirty years old.

As will be noted, the Latin names of bamboos are absurdly complicated to learn. Horticultural boffins have had a field day with this type of plant. Even worse, just as you’ve mastered a particularly silly name, some rotter goes and changes it again! It’s very annoying. Unfortunately, bamboos flower so infrequently that the chance to study them is rare. This means that mistakes in categorizing them have occurred in the past. Renaming them is not done out of vindictiveness or pomposity, but as a result of the latest studies.

On the subject of flowering, this is an unusual event that, from a gardener’s point of view, is a bit of a disaster. Generally, once a bamboo has flowered, it dies. Each type of bamboo tends to flower at the same time, wherever it is. For example, if Fargesia murieliae is flowering in one country, the chance of it flowering at the same time elsewhere in the world is very high. This phenomenon was once attributed to the supposedly supernatural powers of bamboo. Although various other theories abound, a much more boring explanation is likely. After flowering, bamboos set seed. As this happens perhaps only once every hundred years, bamboo enthusiasts seize the opportunity to obtain fresh supplies and a new batch of planting using seed of the same age starts all over the world. So, all new plants are likely to mature and flower again at the same time. I rest my case.

If a small number of different types of bamboo are planted throughout a garden, flowering shouldn’t really be a concern. If you want a screen or hedge of about a hundred plants, then it is important to check at specialist nurseries if anyone has reported seeing your chosen bamboo in flower. To lose one or two plants is not so bad, but to lose an entire hedge would be an expensive mistake. In recent years, Fargesia murieliae and Pseudosasa japonica have both flowered, so, unless you are planning to live an exceptionally long life, it is safe to plant both of them again.

Keen gardeners always want to have a go at propagating their favourite plants. But when it comes to bamboos, the whole process is so tedious and unrewarding that my advice is to leave it to the experts. If you remain undeterred, growing from fresh seed is probably the easiest method. Best sown in spring, the seed is slow to germinate and, after one year, all you’ll have to show for it will be an extremely small tuft of leaves. At the end of the second year, you’ll have a tuft of leaves only slightly less small. After three years, you’ll start to have something resembling a small bamboo, but it won’t exactly be taking up much space.

Another method of propagation is by division. The easiest time to do this is right at the seedling stage, before plants develop strong roots and canes. But the idea of spending a couple of years nurturing a small plant from seed and then slicing it in two seems madness to me unless you’re a commercial grower. Another method, which is great fun to watch but torture to do yourself, is to try to divide large plants. The sheer effort required, the strength to slice through roots and canes using axes, hammers, chisels and God knows what else easily outweighs the benefits of getting a couple of extra plants. I have watched people turn purple and have to lie down to recover from their exertions after trying to divide a bamboo – it’s a guaranteed trip to Hernia City as far as I can see. Please, just save some money and buy a decent-sized plant from a bamboo specialist who has done all the hard work for you.

A question often asked is whether canes can be harvested for use in the garden. The answer is that established bamboos may have one or two older ripe canes that would be better removed, but most canes are best left on the plant. Generally, the only time canes are removed is when they are young and too small to be of much use.

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Fargesia murieliae is an easy bamboo for beginners with lots of lush foliage produced from numerous delicate canes.

Arundinaria anceps

Himalayan Bamboo

SYN. Sinarundinaria anceps

Sinarundinaria jaunsarensis

Yushania anceps

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Lush heaps of shaggy foliage make Arundinaria anceps a popular choice of bamboo.

Grown primarily for its luscious cascades of evergreen foliage, this is a very easy bamboo for beginners. It consists of masses of tiny leaves, densely packed together, which give a soft look to the whole plant. Grown as a single clump, it makes a fine addition to the garden, especially near a pond where it looks resplendent trailing over the edge. And, because of its denseness, it is an excellent candidate for growing as a bamboo hedge.

Arundinaria anceps is a slow plant to get going and seedlings aren’t always successful. Therefore it makes sense to buy a reasonable-sized plant with a well-established root system. Bamboos can be planted at any time of the year unless the ground is frozen or waterlogged, although planting is perhaps best avoided during hot, dry summers, when watering would become a real chore.

For hedging, choose well-established plants with a good root system that are growing in at least 10- or 15-litre pots. Ideally, plants should be at least 90cm (3ft) tall. Spacing depends on your impatience and your budget, but no fewer than one plant per 1.2m (4ft) would be advised. Try to buy plants of a similar size so that when planted out they have a uniform appearance from the start.

Arundinaria anceps is best planted in the spring to give the plants a whole season to start resembling a hedge. Feed and water regularly throughout the growing season, and trim lightly with shears along the top and front whenever necessary, depending on the height and depth eventually required. As with any hedge, not just bamboo, trimming little and often is much better than cutting back hard just occasionally. The more that is cut from the top and sides, the more growth that will be encouraged widthways, which fills in the gaps between individual plants.

After two or three seasons, when the final shape has been attained, regular light trimming twice a year should suffice to keep things looking tidy. Arundinaria anceps