The 19th century's hugely successful cultivation of plants on the once-barren Ascension Island has lessons for us today, says Charles Quest-Ritson.
When our ancestors raised the Union Flag on Ascension Island in 1815, they found a landscape so barren that it could not be used as a supply centre for British ships.
The uninhabited volcano close to the equator had already been rejected as a possible stopping place by the Portuguese navigators who discovered and named it in 1501. In 1725, a Dutch ship’s officer was set ashore on the island as a punishment for sodomy. He died shortly afterwards, of thirst.
Britain only took possession of Ascension after the battle of Waterloo, as a precaution against the possible escape of Napoleon from exile on St Helena far to the south-east. The British Navy did eventually find a small spring in a valley on the ‘wrong’ side of the mountain, however. It produced about 500 gallons of water a day, barely sufficient for the small garrison of Royal Marines, their crops and their animals.
The Marines held onto Ascension Island after the death of Napoleon. Charles Darwin visited it in 1836 during his second Beagle voyage, describing it as arid and treeless, with nothing growing near the coast. Darwin was followed in 1843 by his friend Joseph Hooker, the botanist and explorer. The two scientists devised a plan for greening Ascension to make food growing possible and to produce enough fresh water not only for the garrison, but also for visiting ships.
Hooker’s father was the director of Kew Gardens — which was a help. Father and son began to ship some 220 different taxa — exotic plants from all over the world — for planting on Ascension. They knew that most would die, but hoped that some would flourish. There was no telling which plants would establish themselves, but the survivors would naturalise and develop a new ecology for the entire island that would attract moisture enough to create springs of water. People could settle and Ascension could become a useful coaling and victualling station.
The strategy was a great success and, today, the volcano is called Green Mountain. Halfway down the mountain slopes are plants you would see in a Mediterranean garden, including eucalyptus, casuarinas and mimosas. The drier, unirrigated lowlands support guavas, prickly pears, mesquites (Prosopis juliflora) and Nicotiana tobacco trees from Mexico. The greatest changes, however, are evident in the top zone, above 2,000ft, which is now covered in mist and completely vegetated — a jungle of trees, bamboos and shrubs interspersed by grassy glades.
“Gardeners will tell you how hard it is to sustain a convincing wildflower meadow. Natural gardening doesn’t work.”
Bananas, ginger plants and Cape gooseberries (Physalis peruviana) flourish in the lee of coffee trees, Norfolk Island pines (Araucaria excelsa) and Podocarpus elongatus trees from the Cape. There are swathes of the scarlet Hippeastrum reginae from South America. Right at the summit, there is even a dewpond, filled with blue waterlilies.
The plants that have naturalised at different altitudes on Ascension Island are the survivors of Kew’s 220 introductions. The rest could not cope with the climate or the subsequent competition from other introductions. The vegetation of the island today is an eccentric mix of plants from all over the world.
Some botanists regret the loss of the barren volcanic ecosystem that existed 200 years ago. Our government — Ascension is an overseas territory — concedes that Kew’s botanical interference could be said to have degraded a previously pristine island environment. But I would say, in our defence, that Man has always tried to put uncultivated land to useful purposes. We cannot judge the actions of the 1840s by today’s commitment to conservation.
Kew’s experiments on Ascension Island have two lessons for gardeners today. The first is that survival of the fittest applies as much in the plant kingdom as in other walks of life. There was a gardening fashion in England some years ago for planting a large number of perennials to create a natural garden, but people found, as the years went by, that the weaker taxa disappeared and only a handful of dominating alpha plants remained. Gardeners will tell you how hard it is to sustain a convincing wildflower meadow. Natural gardening doesn’t work.
The second point to ponder is the artificiality of making a garden — how it destroys the natural ecology and how this must be weighed against its benefits. All gardening is habitat destruction. And all gardens have a purpose. We know them to be useful or believe them to be beautiful. Think of those blue waterlilies. Ascension Island is now a garden that satisfies both of William Morris’s criteria.
Rewilding is an absurd fantasy. It undoes the efforts of many generations to make the world a better place.
