Buying larger plants immediately helps to break up this void, by giving definition both to existing planting and to brand new gardens.
These days, it's not only the impatient gardener who will splash out on larger plants to help to create an instant garden. Structural planting - the larger shrubs, hedges or small trees - is frequently used to establish the essential framework in a city garden. Tall, architectural plants with strong evergreen foliage will help to add permanent form.
A strategically placed large specimen can often look better with space around it: setting it in among other plants may choke the space, creating a feeling of claustrophobia. In a small garden, especially, each plant must earn its place. Those that have sculptural qualities - as opposed to just flowering spectacularly for two weeks and then looking a bit messy for the other 50 - will rightly command the space all year round.
Bamboos are great for adding instant height and a dramatic vertical element to the overall composition of a garden. The fishpole bamboo (Phyllostachys aurea) with its pale green canes which turn yellow, and the black bamboo (P. nigra), whose canes start browny-green and turn jet black, both grow to about 3.5m. For very small gardens and roof terraces, bamboos can - in contrast to popular belief - be grown successfully in containers.
Plant in a mixture of 85 per cent compost, 10 per cent composted bark and five per cent grit. A water- retaining granule will help to stop them drying out. Feed and water bamboos regularly.
The Canary Island date palm (Phoenix canariensis) has a graceful arching habit and, being tolerant of temperatures down to -7oC, is hardier than one would expect. It is becoming more widely available as a well-grown plant (2m and over), and is relatively good value for money. It's worth protecting the crown in the winter by wrapping the fronds with some fleece.
Another plant which will give good height with full architectural effect is the phormium. Phormium tenax variegatum has sword-shaped leaves up to 3m long, which are mid green with creamy yellow stripes of varying widths. This versatile plant will look good in a mixed border, or, if grown individually in a container, makes an excellent focal point.
As an alternative to the ubiquitous Choisya ternata, why not try Pittosporum tobira. A bushy evergreen shrub with leathery mid to dark green leaves, its reliable clusters of creamy white flowers will fill a small garden with a heady fragrance in summer. P. tobira will tolerate more shade than you would expect, and can be clipped like a hedge or left to reach its eventual height of 6m.
In shadier areas, the tree ferns will give the sculptural qualities we're frequently looking for. Dicksonia antarctica is the only guaranteed hardy tree fern, withstanding temperatures down to -7oC. In a cold winter it will lose its fronds, allowing it to grow new ones up to 2m long. Quite stunning when, as often happens in a city garden, it's viewed from above. Tree ferns have recently become more affordable, but, as they only put on about an inch of trunk a year, buy it at the required height. As their root system is a matted system on the trunk, they work well in a pot.
As a general rule the more slow growing the plant - the more expensive a larger specimen will be. I think, in a small city garden, it's sometimes worth paying a little more for larger plants. Let's face it - there are worse vices in the world than spending your money on a big bamboo.
Joe Swift is a garden designer and owner of The Plant Room, 47 Barnsbury Street, Islington N1 1TP, tel: 0171-700 6766
Good Plants for Height and Effect
Phoenix canariensis (canary island date palm), hardy to -7oC. Height 4m x spread 2m after 10 years. Prefers full sun, but will tolerate some shade.
Phyllostachys aurea (fishpole bamboo), hardy below -8oC. Height 3.5m x 2m after 10 years. Likes sun but will tolerate dappled shade.
Phormium tenax (New Zealand flax) is hardy to -7oC. Height 3m x 1.2m. Prefers full sun. Do not feed.
Trachycarpus fortunei (Chusan palm). Hardiest of palms (-7oC). The fibrous trunk with fan-shaped leaves will create a classic palm silhouette.
Musa basjoo (banana). Vast green leaves up to 1.2m long. Fleece protection needed in winter even in mildest areas. Sun or shade. Height 2.4m x 1.5m. Feed and water regularly.
Ficus carica (common fig) can be grown as a tree or trained against a wall. The indented leaves grow up to 15cm long. In a good summer it will produce edible fruit. Full sun in well drained soil. Hardy to -7oC. Height 4.5m x 4.5m.
Fatsia japonica (false castor oil plant). Perfect for deep shade. The variegated form will brighten up the darkest area. Fully hardy. Height 2.4m x 2.4m.
Yucca aloifolia (Spanish bayonet). The most beautiful of the yuccas, but is lethal with spiked leaves growing from a trunk which can reach 2m. Frost hardy, but hates damp soil.
Cordyline australis (cabbage tree). Slender sword-shaped leaves on a straight trunk this is a relatively fast growing plant. Half hardy. Grows to about 3m, and needs full sun.Reuse content