Hostas by pond

Photographs: Charles Francis

September 2013: A conversation with head gardener Richard Morton

What is the history of the garden?

The estate was purchased by Edward Bolitho in the 1830s, and by the 1880s, it was mentioned in horticultural journals as having an extensive rhododendron garden. The current layout is mostly the work of Edward’s son Thomas, an extremely keen plantsman. The Bolitho family still live here. The garden has only been open to the public on a formal basis for 12 years; we now open from mid-February to late September.

What are the attractions of Trewidden?

The most important feature is the tree fern pit which has the finest Dicksonia antarctica stand in the country. The first ferns were collected from the wild in Illawarra, near Sydney, in 1898. The pit is reputedly the oldest site of tin extraction in the country. It may be Roman, so you could be looking at a 1,800-year-old hole in the ground.

Fern pit

Until the 19th century, this was still a tin mining area. The Bolitho family had smelting works in Penzance, and we have mining artefacts, like smelting kettles and tin ingot moulds, which were brought here as garden ornaments. We also have a walled garden, some very large, fine specimens of magnolia, and several champion trees. Six of our biggest trees were involved in this year’s Golowan Festival in Penzance, which had the theme of Giants: people could go round the garden and find the trees. We had many positive comments, and we hope to link into Golowan again next year.

How is the garden developing in the 21st century?

We are trying to maintain the tradition of the early 20th century plant-hunters by experimenting with new, unusual and tender plants, like Schefflera macrophylla from Vietnam, which has only been available in cultivation in the west for 12 years. Historically, Trewidden was a spring gardens, but we’re now starting to create colour throughout the seasons, from camellias, magnolias and rhododendrons to summer-flowering perennials and shrubs.

Lilium regale

Lilium regale 

In the walled garden, we are making more mixed borders — hot, colourful places for people to sit — and we are clearing out overgrown laurel to create sun-drenched woodland glades. We’ve restored an 1890s waterfall in the rock garden.

Rock garden waterfall

One problem is, as with all great gardens, some trees and shrubs have become over-mature and created too much shade: if you’re going to plant a lot of summer-flowering things, you need sun. But you don’t want to clear areas indiscriminately, which leave you open to autumn and winter gales.

What are your current projects?

Visiting Trewidden is like walking around a family garden, and we want to keep it like that. We plan to cut back more laurel, as I’d love to give people a full view of the fern pit, as it is so significant. We’re hoping to restore one of our two ground vineries, probably the last two left in Britain. They are like mini greenhouses, and were popular with the middle classes in the Victorian and Edwardian period, when they were known as curate’s vineyards: if you had a town villa, you could grow dessert grapes under glass. Most were made from timber and haven’t survived, but ours were built in brick and lined with slates to give warmth.

How has the unpredictable Cornish climate of recent years affected Trewidden?

We have had to get used to the lurch between torrential rain which washes the paths away, and cold and very dry conditions. In May, storm force winds went through the garden like a tornado and blew over a large turkey oak. But sometimes disasters are good. Last year, a Moroccan cedar tree fell, which opened up the view of Magnolia x veitchii ‘Peter Veitch’ overlooking the pond — a mass of flowers in spring. Because of the low light levels and lack of heat during the last few summers, some plants haven’t been able to ripen and harden up, which makes them susceptible to damage in the winter cold.  But after several weeks of hot sunshine this summer, many put on a lot of growth, and the mixed borders are standing upright, rather than flopping over from the effects of wind and rain.

Richard Morton with Puya chilensis

What can visitors see in September?

All round the garden, there are different hedychiums — hardy gingers from China and the Himalayas — and they have come into growth a lot earlier this year, so should be well in flower in September and before. Last year, because it was so cool and damp, some of them didn’t flower until after we’d closed. The pond garden and the mixed borders in the walled garden should also be colourful, and the fern pit looks good at any time of the year.