WHATEVER THE WEATHER
The landscape designer Tom Stuart-smith reveals how to help your plants thrive, in sunshine or in rain
As one of Britain’s foremost landscape designers, Tom Stuart-smith is more aware than most of how the changing climate is affecting our gardens. Over the last few decades, he has become internationally acclaimed for his intelligent and innovative approach to planting, his many accolades including eight gold medals at the Chelsea Flower Show, a retrospective at the Garden Museum and a major ongoing commission to oversee the establishment of a new RHS garden at Bridgewater, near Manchester, which is due to open in 2020.
The gradual shift in weather conditions means certain plants are struggling with the hotter, drier summer months, especially in London and the south-east. ‘Increasingly, you’re treading a balance between hanging onto the old English idyll of lush growth, cultivating blooms that require quite a lot of fertility and moisture – such as delphiniums and peonies – and introducing new varieties that might be better able to cope with our summers, which are now slightly hotter and have longer periods of drought,’ he says.
Mediterranean plants are well-suited to such conditions, as are species native to South Africa, Taiwan and the middle part of Japan, which were previously unable to survive our historically harsh winters. In Stuart-smith’s own garden, at Serge Hill in Hertfordshire, he has sown a large meadow of exotic species, almost entirely grown from seed. It includes drought-tolerant plants from the prairies of North America, such as the thistle Eryngium agavifolium and the white-flowered Euphorbia corollata, and begins to flower at the end of June, continuing right the way through to September, and bringing some much-needed colour into late summer. In another recent project, designing outdoor spaces for the Glebe, a new apartment building in Chelsea, he has used tender plants that like sun and heat, including olives, myrtle and loquat.
However, it is not as straightforward as simply selecting more southerly species and expecting them to thrive. Unseasonable weather, such as the extreme cold spells in March and early April, wreak devastation on the most carefully planned schemes, requiring gardeners to be more vigilant and to act quickly if required, moving containers indoors and protecting larger exotic plants such as palm and tree ferns with well-insulated fleece bags. Although Arctic temperatures can be destructive, StuartSmith believes that the real challenge of climate changes comes from the increased rainfall in the winter months. ‘A lot of plants hate the wet, especially the drought-tolerant varieties,’ he says. ‘Too much of it will kill them.’
To avoid unnecessary losses, he recommends simultaneously improving drainage and cutting down on irrigation. ‘It’s best to go for a leaner approach, using gritty, sandy soil that’s well drained. Don’t fertilise the plants or water them too much – you’ll get better results if you treat them as if they were in their natural home. Plants grow more slowly like this, but there’s no point being too hasty when it comes to gardening – you always regret it.’
Another potential peril is the possible introduction of new botanical diseases, now that so many of our gardening supplies are imported, from plants to gravel and sand, while long spells of damp and mild weather allow bugs and bacteria to take hold. Most gardeners are still unaware of the danger posed by new diseases, but larger institutions are already taking steps to cover themselves – the RHS has recently imposed a one-year quarantine on imported plants intended for its gardens. An easier solution is to buy locally, choosing nurseries that grow their own stock, and researching the provenance of anything you buy online.
Ultimately, although change is certainly happening, it is possible to adapt to it gradually, using the opportunity to explore new varieties to add life to existing schemes. If Stuart-smith’s spectacular gardens are any indication of what the future will look like, it’s very bright indeed. www.tomstuartsmith.co.uk