The relationship between gardeners and conservationists is not always an easy one. There is no doubt that horticulturists have introduced many of New Zealand’s pest plants, usually thinking they will make a wonderful addition to our gardens.
You can perhaps excuse our first European forefathers for introducing gorse, because they had no idea that the plant would grow so crazily in New Zealand conditions, but the introduction of other plants has been in a cavalier manner – and our environment pays the price. The way old man’s beard spreads is shocking, especially in forest margins, but other introduced climbers introduced more recently can be just as bad. I have seen the effect of planting the Chinese jasmine, J polyanthum too close to forests and see how quickly it completely smothers other plants. It looks pretty and has a delightful fragrance, but it is a thuggish brute once it gets underway.
Gardeners have had another effect on the world of plants. Some species have been wiped out in the wild because of our passion for collecting colourful specimens. This particularly applies to orchids, but many other attractive flowering plants have been threatened by our desire to have beautiful plants around us.
There is a way we can set about redressing the balance. Masterton gardener and retired horticultural teacher Alan Fielding is proposing that each territorial authority in New Zealand adopts a plant that grows in its district and encourage its use in both public and private gardens. That way gardeners can provide a reservoir of endangered plants that can be used to repopulate the plants in the wild.
Masterton residents are lucky enough to have an attractive endemic plant growing wild on our coastline – the Castlepoint groundsel, Brachyglottis compactus. Anyone who has clambered over the reef or scaled the heights of Castle Rock will have encountered this low-growing shrub, marked by its masses of yellow daisies over summer. The leaves are green, with wavy edges, and covered with tiny white hairs on the underside and Castlepoint is the only place in the world it grows naturally.
There are several other Brachyglottis species, including the popular garden plant B greyii, also found on the Wairarapa coast but further south. There are many hybrids which feature both these plants, perhaps properly called the Dunedin hybrids after the place they were first raised, but they are usually sold in the trade as though they were the wild species B greyii.
The Castlepoint groundsel is not as well known but deserves to be more widely grown as it is a very hardy shrub, well able to cope with coastal conditions, but equally well suited to growing in quite harsh conditions inland. It does not seem that any Wairarapa frosts will damage it, and despite the coastal look of its foliage, it also seems to be able to cope with quite a bit of shade.
This unique piece of Wairarapa’s botanical heritage is listed as being at risk because of its restricted distribution, so it would be good to have other populations established away from the coastline.
There are plenty of other New Zealand species which can benefit from this treatment, and there are even some that have.
There is the remarkable Three Kings climber, Tecomanthe speciosa. This vigorous [actually, very vigorous] member of the Bignonia family was found in 1940 – or at least, one plant was. Apparently, it was probably once common on the islands, but goats had been liberated there and had happily munched their way through the majority of the plants, leaving just one plant to be found.
But what a plant it is – extremely strong growing, with succulent bright green foliage, then over summer bunches of large creamy-green flowers of typical Bignonia bell shape. This wonderful climber needs a warm spot, as you might expect from a plant coming from an island in the north of the North Island, but if you have the room for it, it is spectacular.
Another one of New Zealand’s spectacular garden plants is also very rare in the wild and has possibly been saved from extinction by being collected for the garden. The red [and pink and white] kakabeak is one of New Zealand’s most popular garden plants, but there are reportedly less than 150 plants left in the wild, many growing in difficult sites on the East Coast, where they are at danger from exposure to the storms that have wreaked havoc in the area. Fortunately, they are popular garden plants, and they now appear to be safe.
Although it is nowhere near as spectacular in flower, the humble tororaro, Meulenbeckia astonii is a another plant that has been rescued by gardeners. Once very threatened, this small shrubby plant is now a popular feature of modern New Zealand gardens.
However, it must be said that this is one of those plants that you either love or hate – and the Head Gardener has her feet firmly in the second camp. Her problem is the extravagant tangle of zig-zagging branches that carry sparse numbers of small leaves. Personally, I love it but haven’t managed to smuggle one into the garden yet.
