I have always had a healthy suspicion of the concept of gardening as art. Surely, it’s a practical pastime, driven by practical issues-the weather, the seasons, a knowledge of plants. But there is one area that has a crucial element of artistry and, for anyone gardening principally with plants rather than architecture or ornament, it is the secret ingredient of success: plant association. It is the skill of knowing how best to combine the qualities of plants so that they grow together to mutual enhancement.

Gertrude Jekyll knew this when she wrote 100 years ago: ‘In practice it is to place every plant or group of plants with such thoughtful care and definite intention that they shall form a part of a harmonious whole, and that successive portions, or in some cases even single details, shall show a series of pictures.’

I have now had confirmation of how elusive this skill is as I review the early results of my efforts in a new border at Goodnestone. Admittedly, we were working on an ambitiously large canvas. The area is a border of prepared soil, 180ft long by 15ft deep, and in early April, we put in just over 400 bought-in plants, plus some 300 we had already grown ourselves in readiness for the occasion. I can already see that some plants are in the wrong place, and that in a few months’ time, when they are all safely dormant, many will be moved-and some removed-as we work towards achieving Miss Jekyll’s elusive ‘series of pictures.’

The border has been made in front of a west-facing brick wall in a middle section of the walled garden. Last year, we tore up what was there, levelled the site and redesigned it around a new central water rill. It’s exciting to see what was a long stretch of bare earth beginning to take shape and contribute to the wider picture of its setting. And it’s worth emphasising the elements that enabled us to plan and plant with an degree of coherence.

For structural effect, we subdivided the long sweep of the border into three sections by planting two lines of yew that will be clipped into solid green year-round buttresses. I first saw this idea in the famous Victorian herbaceous borders at Arley Hall in Cheshire. At Goodnestone, the yew interventions enable us to plan the border as three adjacent sections-or pictures. This has certainly assisted two other factors: colour and seasonality. It has given a framework to the progression from predominantly white at one end to dark purples and reds at the other, and enabled us to plant the white area to come into flower earlier than the key mid-to late-summer season.

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We decided that the plants would be almost exclusively herbaceous, but deliberately chose ones that would be as self-sufficient as possible in not requiring staking or attention for pest or disease control. We chose a good proportion of large plants on the basis that, once grown to maturity, they would be in bold proportion to the overall size of the border. We planted them in generous groups-usually three plants the same, often five-and varied the shapes of these groups from circles to oblongs and narrow ribbons, in the traditional way.

I think we have avoided overplanting, which is a temptation with such a large area or if you are impatient. Planting densely brings the short-term satisfaction of seeing a large area filled out in the first season, but it is inevitably wasteful. Within a year or two, everything has outgrown its original limited position and, rather than a well-ordered neighbourhood, you have a horticultural squatter camp from which many inhabitants will have to be forcibly removed. Instead, we will watch the plants grow to optimum size through two or three seasons, during which time, we can see how the picture is coming together as planned, and adapt it as required.

George Plumptre’s family garden is at Goodnestone Park, Wingham, Kent. Visit www.goodnestoneparkgardens.co.uk for opening times.

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