Bamboozled! by Martin Cox - Daily Mail 8 November 2010
One expert's masterclass in taking the pain out of creating stunning canes
Bamboos are hard to beat for year-round colour, structure and style, but ignore these Oriental beauties at your peril.
Without a helping hand, some plants will outgrow their allotted space, elbowing less robust plants out of the way. For a masterclass on how to look after bamboos, there's no one better than Paul Whittaker. For 25 years he has run PW Plants in Norfolk and sells almost 200 varieties.
Some plants are 40ft high with canes the size of your wrist. 'Some people let their bamboos get out of hand, but they're remarkably easy to care for and it won't take long to rejuvenate a neglected plant,' says Paul, 53.
Closely related to grasses, bamboos hail largely from China, Taiwan, Korea and Japan. Plants expand sideways via underground runners that send up new shoots or canes.
Paul divides his plants into three groups: 'clump formers' that spread slowly; 'runners' that can be invasive; and those somewhere in between, which he calls 'running clumpers'. Perhaps the greatest worry gardeners have is how to control invasive bamboos.
'The key is to start off with a bamboo that suits the size of your garden, but if you've inherited a spreading variety, there are a number of ways to keep it under control,' says Paul.
'If you see a shoot popping up where you don't want it, kick it off at ground level as soon as you spot it or it will become difficult to remove.' He also suggests curbing the spread of established plants by digging a trench around the portion you want to remove, then undercutting with a spade.
Another way to restrict growth is to install a barrier below ground – paving slabs placed vertically are perfect, but avoid butyl pond liners as they are easily punctured by the tapered point of a runner.
The barrier should be 3in above the soil line to prevent runners escaping over the top. Fill gaps between slabs with a silicon sealant.
If you use a fabric barrier, make sure that the ends of the material overlap by around 1ft and secure them with appropriate glue. Apart from keeping bamboos within bounds, you can prune them to make them more presentable.
Many varieties have colourful canes that are often disguised by the flush of leafy growth that develops in spring. To reveal the showy stems, strip the leaves from the bottom third of plants to raise the canopy. 'Some people snap off side branches with their fingers, but this can rip the canes if they don't come off cleanly.
'To avoid damage, cut off branches flush with the stem with a pair of secateurs,' advises Paul, who has won 47 Gold Medals for his displays at RHS shows.
To thin out established clumps, he recommends cutting out weak canes to ground level, which will allow light and air to reach the crown of the plant and improve its look. As they grow taller, many bamboos bow under the weight of foliage. To stop this, simply snip off the top.
Not only is autumn the best time to maintain plants, it's a great time to plant bamboos. Dig a hole the same depth as the container and a little wider. Water the plant well and leave to soak for an hour.
Then remove the pot, place the root ball in the hole and slowly fill with soil before spreading a 2in layer of leafmould, garden compost or well- rotted manure over the planting area.
If you have room, Paul recommends Phyllostachys vivax f.aureocaulis, noble bamboo (Semiarundinaria fastuosa var. viridis) or phyllostachys bambusoides 'Allgold'. 'And Phyllostachys iridescens is extremely desirable – I have a waiting list for them,' he says, pointing to a grove of dark green canes that rise 40ft in the air.
Black bamboo (Phyllostachys nigra), Fargesia robusta and Borinda albocera, which has pale yellow-green canes, are best for smaller gardens.