Subtropical trees provide structure to a garden as well as overhead protection from the sun. Unlike their somewhat dull temperate counterparts subtropical trees are often showy and colourful. This description applies equally to sub-tropical bushes being, in the main, bright and colourful.
Here we present just a few subtropical bushes and trees for New Zealand gardens.
There are no shortages of subtropical bushes that thrive in New Zealand gardens. Many are well established and we bring them together here as examples of companion plants for palm trees.
In discussing subtropical bushes, we begin with the bright and showy Hibiscus. In northern New Zealand Hibiscus plants have been a familiar sight in gardens for years. Most plants are either Fijian (smaller flowered) or Hawaiian (larger flowered) hybrids. Excitingly however there are also large flowered (15 to 30cm diameter flowers) Hibiscus that are incredibly hardy. We’ve grown some of these in London and they don’t even notice the frosts returning to flower year after year. Perhaps even more exciting are the new hybrids with the most indescribably beautiful mottled petals that are gradually making their way onto the market.
Three genera of subtropical trees which have great potential for the subtropical garden are Ficus, Erythrina and Dombeya. Ficus are most commonly represented in northern New Zealand by the Rubber Fig, Ficus elastica. One should not however forget more spectacular species such as the gigantic Moreton Bay Fig, Ficus macrophylla, seen in old parks around the north. Another rarely seen fig worthy of inclusion in the right garden is the Highland Breadfruit, Ficus dammaropsis, a tree with huge pleated leaves 60cm across.
If beauty and fragrance are your thing then consider the Brugmansia or Angel’s trumpet. Flowers span a range of colours including white, cream, pink, yellow and orange. Flowering tends to occur periodically every couple of weeks during summer. The delicate and subtle scent of a flowering Brugmansia is beyond description on a warm summer’s night.
Another subtropical bush that’s been popular for a while now is the Vireya Rhododendron. Requiring an almost frost-free climate these tropical rhododendrons bloom in a range of vibrant colours that rival even the brilliant Hibiscus. When planted in a sheltered rainforest garden they provide colour often lacking in other suitable plants.
Yet another subtropical bush to complement palm trees is the Abutilon. Tough, relatively hardy and quick growing these bushes flower in a range of colours for much of the year.
The Coral Tree or Erythrina family represent over 100 species of bright and showy trees. Often deciduous they tend to flower in spring when otherwise leafless. Whilst predominantly tropical the Erythrina genus does have several semi-hardy species that grow well in northern New Zealand. The hybrid, Erythrina x sykesii, is a reliable grower here and was in fact first identified as a hybrid in New Zealand.
For a subtler colour the Dombeya genus is worthy of consideration in milder parts of the country. Dombeyas are relatively fast growing, tropical looking small trees with bunches of pink flowers. Established species in New Zealand include Dombeya burgessiae, Dombeya torrida and Dombeya ‘Pink Cloud’.
For a subtropical tree that looks like nothing more than a tree fern consider the Brazilian Fern Tree, Schizolobium parahyba. This is a magnificent fast-growing tree that does well in near-frost-free parts of northern New Zealand. To cap it off, this plant is known for its anti-snake-venom properties. Which perhaps isn’t so important in New Zealand.
Finally, for the Mediterranean garden one cannot overlook the humble Olive Tree. Developing gnarled trunks with age these – and perhaps grape vines – epitomise the Mediterranean and look fantastic when combined with rock gardens, blue/grey palms and succulents.
See Garden Designs using Palms, Cycads and Subtropical Plants for more suggestions about combing palms with subtropical bushes and trees.