How to Build a Subtropical Garden
The so-called subtropical garden is really a trick. We are used to seeing in our gardens plants from all over the world, from the most extravagant rhododendron to the most delicate alpine primula; but usually these plants come from a climate broadly similar to our own. In the subtropical garden, the aim is to present a picture of a totally different climate in which the usual range of temperate plants will not grow. To do this is inevitably a deception, but a satisfying one.
The subtropical style of gardening involves using a range of plants which might seem more at home in a much hotter climate, although they must of course be able to grow in our own gardens. It is achieved by selecting those plants with the most appropriate foliage; but perhaps more importantly, it is achieved by avoiding those plants which are commonplace in temperate gardens. The absence of certain plants is just as telling as the choice of plants used.
By the same token, subtropical gardens are often best sited in an enclosed area where the presence of the temperate world outside cannot dilute the effect you are trying to achieve. The same goes for garden architecture, furniture and hard landscaping. It is better to avoid the hallmarks of other garden styles such as classical urns and familiar, traditional garden seats and paving techniques. Instead, try to keep hard surfaces as informal as possible. Gravel is the most discreet option but clay tiles are another possibility. Stay with unsophisticated materials wherever possible. Cane or bamboo seats will look right.
Water can be important in creating a subtropical garden. If you want to give the impression of a hot dry climate, then a pool or a fountain is ideal. If the aim is to reproduce a jungle effect, running, trickling or dripping water may be more appropriate, with moss and ferns growing alongside to enhance the effect.
Subtropical climates tend to produce large, lush foliage and this should be imitated in your choice of plants. The paddle-shaped banana leaf is to be found in carinas and lysichitums; spiky rosettes are found in yuccas, cordylines and potted agaves; araucarias can be useful too. For sheer size of leaf, there is no beating the Chusan palm, Trachycarpus fortunei, and paulow-nia and ailanthus trees can be stooled to produce huge leaves. Gunnera and Rheum palmatum both produce huge herbaceous leaves in damp soil and in similar conditions bamboos and phormium can be used to give an exotic touch. In dryer conditions, Melianthus major offers lush blue-grey foliage. Climbers such as passion flowers, gourds and menispermum can add a tangled, jungle flavour, and daturas in pots will provide wonderfully exotic trumpet flowers rather like a hibiscus. In general, however, foliage is a better tool than flowers in creating the effect of an alien climate: it can offer the promise of subtropical flowers without ever giving the game away.
In some climates it is necessary to create the subtropical effect under glass or at least partial cover, where the higher temperatures and reduced winds will better suit many large-leaved plants.
