Take a video tour of garden designer Alasdair Cameron's rural idyll in Devon

There is more formality at the front of the house but, even here, it is kept to a minimum, with the emphasis on a view over a meadow grazed by the family’s small flock of sheep. The existing front garden enclosed by a listed ironwork fence was retained, with the planting beds extended outwards to make it feel more in proportion with the house and to give the space a sense of enclosure, like a secret garden. Silvers, mauves and pale yellows are the keynotes here, chosen to complement the honey-toned limewash of the house. The plants, including Anthemis tinctoria ‘EC Buxton’, artemisia, Aster x frikartii ‘Mönch’ and Santolina ‘Primrose Gem’, are soft and unstructured, woven together in a romantic and seemingly haphazard patchwork that has the feel of a sophisticated cottage garden. The front garden was also extended to the side, edged with a line of pleached hornbeams and beech domes to screen a parking area. A large border for dahlias and cut flowers adds a glamorous element.

But it is the back garden that really comes into its own as a family space. Punctuated by clipped beech and yew domes and the looser forms of medlars and Viburnum opulus, the lawn is ideal for croquet, football, bike-riding, hide-and-seek and other games devised by the Cameron children. Screened behind the curved border by a hornbeam hedge is another area with a tree house, zip wire and large vegetable garden, where Alasdair and Tor grow as much of their food as possible.

Our tour of the garden ends where it started, with the long border, which in late summer and autumn draws the eye across the lawn. Even at this time of year, the planting is still in full swing, with towering late-summer perennials and grasses in dusky, muted colours with dashes of orange from rudbeckias and heleniums. ‘I like to think of the river as an influence,’ says Alasdair. ‘The key structural plants are like river boulders, with everything else flowing and bouncing around them. I like to run particular plants through a space, then drop out into something else. It’s about rhythm and crescendo, and then bringing it down again.’ Key upper-storey plants for this time of year are Verbena bonariensis, Eupatorium maculatum, Helenium ‘Moerheim Beauty’ and purple Salvia ‘Amistad’, interspersed with backbone shrubs such as Elaeagnus ‘Quicksilver’ and Cotinus coggygria. The eupatorium creates particular impact marching along the back of the border at 2.5 metres tall, its colour complemented by the haze of purple-hued Panicum virgatum ‘Warrior’.

‘I plan planting schemes that I know will work, putting together different shapes, textures and colours that are contrasting but have a sense of unity,’ says Alasdair. His trick for creating the seamless seasonal flow through the year is to have a monthly chart next to him when he is drawing up the plans, so he can make sure there are plants that will draw the eye at any one point in the year. ‘I did make planting plans for this border but, when I come to plant out, I never use them. I’m pacing up and down, working out the composition, trying to create a linear flow, but also moving things backwards and forwards. It’s a bit like painting – you just need to be intuitive and trust your instincts’.