Visit the gardens at Barnett Hill in Wonersh

PUBLISHED: 10:22 07 September 2015 | UPDATED: 15:01 07 September 2015

Massed dahlias in the formal garden at Barnett Hill

Massed dahlias in the formal garden at Barnett Hill

Leigh Clapp

At the spectacular Barnett Hill in Wonersh, Della Connelly continues the garden tradition that began back in 1905

Estate manager Della Connelly, pictured with her dog Stig, has extended and developed the gardensEstate manager Della Connelly, pictured with her dog Stig, has extended and developed the gardens

Originally published in Surrey Life magazine August 2015


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Barnett Hill, Wonersh GU5 0RF

Visitors are welcome by advance arrangement and on NGS openings

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Once home to Frank Cook, the grandson of the travel agent Thomas Cook, the Grade II*-listed Barnett Hill in Wonersh is now an event and conference centre – and this month the stunning gardens open for one day through the National Gardens Scheme.

Built in 1905 on a wooded hilltop, 360 feet above sea level, the Queen Anne-style house gives magnificent views over the Surrey Hills, including glimpses of Guildford Cathedral from the woodland walk, while the gardens are a treat in themselves.

“Back in the early 1900s, Frank Cook had the site landscaped, transforming it into terraces, herbaceous borders, a formal area with a lily pond, paved areas of York stone and yew hedge boundaries,” says estate manager and head gardener, Della Connelly, who has been overseeing the gardens since 1993. “The planting, as was fashionable of the time, concentrated on trees and shrubs, such as planting beech, rhododendrons and azaleas, with 14 gardeners caring for the gardens to keep everything in perfect condition.”

Colourful history

When Frank died in 1925, his widow remained in the house until she handed it over to the Red Cross and St John War Organisation to use during World War II as a convalescent hospital. Four years later in 1949, Mrs Cook found the property too large to look after and passed over the deeds of the house to the Red Cross who subsequently turned it into their National Training Centre. When running costs proved too high in the mid-1970s, the 
Red Cross decided to open the property to the business world with commercial courses and conferences. Then, in 1996, they leased the property to the Chudley family, who run the Sundial Group, and they later purchased Barnett Hill in 2005, expanding the scope to include weddings, B&B accommodation and events, as well 
as conferences.

Today, Della has taken on the horticultural mantle from the succession of only four head gardeners that have guided the landscape before her. While the gardens continue to evolve with new plants and projects, the ambience and sense of history remains, partly from the planting and structure but also from the teahouse, summerhouse and greenhouse, all in their original condition, that give a glimpse into the past. Continuing the evolution of the gardens, however, 
means keeping the ideas fresh. “I think my style is a little bit eccentric, as shown by planting echiums in the middle of a winter bedding border,” says Della. “I’m a plants person so tend to find plants I like and then put them in with what I have already got, rather than plant to a design.” Self-sufficiency is important with plants not generally bought for the garden, but rather growing from seed, and many plants from friends that can then be propagated to increase the stock in the garden. Plants are also sold on open days allowing visitors to take away a little of the garden as well.

Opening the gates

Opening for the first time through the National Gardens Scheme this August, the event is timed to see the borders reach their zenith, the dahlia beds at their brightest and containers billowing with colour.

In late summer, the herbaceous borders sizzle with vibrant shades from rudbeckias, heleniums, showy dahlias and spires of salvias, with any gaps filled with annuals, including massed zinnias fringing the edges. Some plants have been thriving away for over 25 years, such as sedums, with new varieties added to the mix as they do so well in the sunny, open conditions.

Looking along the border, to the bananas, Ricinus communis (castor oil plants), ginger lilies and cannas towering above textural perennials, you get a sense of Della’s ability to experiment creatively with the planting. She has also introduced beds of wafting grasses, such as Stipa gigantea, bamboos, Arundo donax and Miscanthus sinensis ‘Gracillimus’, along with the impact of architectural tropical-looking foliage. And don’t miss the latest project of wildflower beds by the accommodation blocks.

“When you’ve been in the garden for 21 years, you are forever thinking what can I do differently,” adds Della. “It’s a great privilege to garden in such a lovely environment, guiding the continuing development.”


Get the look...

• Add traditional early 20th century features such as a summerhouse and greenhouse

• Opt for hedging on the garden boundary and to separate areas

• Make a feature of a paved terrace with seating a focal point

• Formality can be achieved with a lily pond framed by borders

• Include massed vibrant dahlias amongst herbaceous planting

• Design long borders with low planting of annuals, such as zinnias, backed by mid-height sedums and heleniums, graduating in height through salvias to onopordums, cardoons, cannas and bananas

• Include an eclectic mix of hardy border choices and tender perennials that can be kept in the greenhouse through winter and then brought out into the borders

• Choose bold foliage to contrast with more ephemeral choices such as gaura and cleome

• Plant an abundance of annuals into any gaps in the borders

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