Life in the subtropics

So it would appear summer has arrived with sunny days and soaring humidity, just the weather wet subtropical plants relish. Putting on a particularly good display at present is the shell ginger, Alpinia zerumbet syn. A. nutans and A. speciosa. The genus is named for and Italian botanist Prosper Alpino, (1553-1616), and consists of some 150 species found throughout south and eastern Asia. While the common name says ginger, it is not a weed. My plant while the stems have reached to about 2.5m the base clump is still only about 50cm across after four years. The stems are long (up to 2.5m) and support glossy green lancelet leaves. The flower buds emerge from the tips of these stems in bunches of fat white buds tipped in pink that hang gracefully down like some exotic jewellery. As the buds open they reveal a spectacular flower petal coloured red in the centre and merging into yellow on the outside. The flower does not have a scent, but is so eye catching it doesn’t matter. Mine leans and weeps its blooms over the top side of the driveway where visitors encounter the beauty of the flowers at eye level.
The shell ginger is not the only ginger worthy of mention. Here I should state and name the two gingers of concern to the environment, weeds in other words. Firstly is the kahili ginger Hedychium gardnerianum and yellow ginger H. flava. These two species are from a genus of some 40 species, spread through south and east Asia and one on Madagascar. These two problem species are so mostly because of their ability to set large amounts of seed and also spread by means of stolons, underground stems, similar to running bamboo. I do remember Mum growing kahili ginger on the farm in the Wairarapa. It had a tough time here on account of the climate, and so we did get to enjoy the heady perfume of the flowers by the front gate. I would be hesitant planting it anywhere now, as the weather seems to be getting ever warmer and unpredictable. There are three others in this genus worth a mention, white ginger H. coronarium with white highly scented flowers, red ginger H. coccineum naturally with red flowers and H. greenii with orange blooms. Of these I have H. coccineum and H. greenii, neither of which do terribly well, I suspect this to be on account of there not being enough moisture for them.
Another genus to fall under the banner of ginger is Heliconia. The most commonly grown of this genus is H. subulata, a native of Central America. The foliage is reminiscent of banana, but on much shorter stems, only up to a couple of metres when grown in good rich moist soil. Mine unfortunately get thrashed in the westerlies that belt up the driveway in the spring making the leaves look a little tatty. Still the reward of the flowers at this time of year makes it worth while. The blooms emerge as red spikes which open out to reveal yellow petals. Many of the species are too cold tender to grow here, a pity, as they also make wonderful cut flowers lasting for weeks in water.
Flowering also at the moment along side these gingers is pink datura, Brugmansia suavelons ‘Noels blush’, named for the great Whitford gardener, the late Noel Scotting. The flowers are like large trumpets hanging below a canopy of felt textured leaves. In the evening the flowers have a heady perfume, which may not be some people’s liking. Be wary of planting next to a bedroom window as it is said the plant is an hallucinogenic, but whether this is carried merely on the scent of the flowers I don’t know. The shrub needs to be lightly pruned after flowering to keep it fresh and youthful, if only we could do the same!