It’s also very odd. Gordon Cooke, who is a potter, bought one half of a grand Victorian semi in Sale, Cheshire, in 1986. Behind it and alongside it he made an L-shaped garden. Then, ten years ago, he bought the house and garden next door. But it wasn’t the other half of his own semi – it was the facing half of the next semi along. Now he had two houses and between them a T-shaped garden rather obliquely approached through two back doors. It was all very indirect. What would you have done with it? Gordon’s way of handling his odd polygon was to put two main diagonal paths across the whole space – the St Andrew’s cross, always a good way of making an irregular space look comfortably organised.

Not surprisingly, one of those diagonals is the big vista of the garden. It runs out from the conservatory through a sunken, heavily planted pergola and a screen wall silhouetted with pots, across a meeting space with the other diagonal, and down a formal narrow pool to a mirror on the opposite garden wall. There is a heck of a lot going on here: changes of level are used and implied in the water, there is light and shade, temptation to divert sideways from the path or even to walk into the imaginary space beyond the mirror. The mirror is perfectly positioned: it is tilted sideways so you do not see yourself reflected in it, and its top and sides are hidden in ceanothus, ivy and clematis to make it seem like a tunnel into another garden. What you do see in it, as a prelude to that hidden world, is the reflection of one of Gordon’s stacked-stone sculptures.

Although Gordon now splits his time professionally between potting and teaching, he spent five years during the Seventies, after training as a potter, designing people’s gardens while also working with his father on the farm and living at home. Gordon’s grandfather had been a head gardener, so his flair with plants may well be inherited.

What anyone who has visited Gordon’s garden remembers above all is the cave. It’s a kind of exposed grotto, with one wall removed. It came about because he wanted to make an outdoor covered seating area, but didn’t want to give up planting space. The answer was to garden the roof. And so he dug a pit, and over it erected a plywood dome, which he then covered in concrete, and finally, soil. “We dug down,” he says, “to make that secluded feeling, and partly to avoid the kind of height which would have required planning permission.”

The result today is a sunken pit behind a wide arch of stone. Overhanging the cave mouth are the dripping pale-pink flowers of Fuchsia magellanica var. molinae and the grey paddle leaves of Othonna cheirifolia. Inside, the floor is of coarse, brown bark chips which are soft underfoot and help to create a very private acoustic in the cave. The ceiling is tessellated with small ceramics, and in the back corner is a barbecue complete with hobbit chimney. In the mouth of the cave, tender Begonia sutherlandii grows in the bark alongside cane-stemmed Iris confusa. “In the winter, we can use it as a place to wheel in pots of tender plants,” says Gordon.

On one side, built into the wall, is a bench that curves up toward the roof like an Egyptian couch, from which Gordon can watch the sun set. You might think it sounds pretty, but it’s not. It’s all very blunt, from the loose brown bark to the hard blue bricks that edge the entrance. Nothing is prissified. It’s also very much part of the garden’s design: the arcs which define it tie in neatly with nearby arcs of planting and contrast with the tangents and straight lines of the pond and paving beyond.

This is a true plantsman’s garden, and not just of trendy plants. There are traditional moments when groups of delphiniums stand proud, honesty and cosmos froth around, wistaria smothers the pergola, and light falls through the skyscape of golden Robinia pseudoacacia ‘Frisia’, Genista aetnensis, catalpa flowers and eucalyptus. There’s even a tiny wedge of lawn towards the house, set with white wire chairs. But there are more fashionable moments too, where cannas and grasses rub shoulders and a purple cordyline acts as a roundabout where the diagonal paths meet. In fact, the whole garden displays a surprisingly scattery planting. “The designer in me would love to plant in big swaths,” says Gordon, “but it would feel like a waste. I want lots of different plants, new plants to try. Sometimes I think I’d like to start the whole garden again, but the plants give so much back I couldn’t bear it.”

He likes to experiment with tender plants. There’s a big acacia which in this year’s slow-but-steady spring flowered yellow for a month. Against a wall there stands a big mounded bush of Euphorbia stygiana, looking like a souped-up Euphorbia mellifera. And on the roof of the cave, draining is so good that a rosette of fat-leaved Kniphofia caulescens is able to thrive, looking as though clamped on by its toes.

The great risk in potters’ and sculptors’ gardens is that the owners overdecorate them with their work. Gordon just about gets away with it by making most of his numerous pieces throwaway lines. They sit lightly among the plants, sometimes partially hidden. Occasionally they will spike up through the planting or stand en masse, trellis-like, in the pergola’s geometric screen. Periodically Gordon holds an exhibition in the garden, and tucked away in the shade at one side he has made a mini-gallery of slate and concrete plinths supported by simple blocks of greenery. Underneath are a few splendidly complex touches of paving that make the exhibits look less alien, but they are made of imperfect, unpretentious mix-and-match materials – broken slate, York stone, tiles and glazed bricks. Even so, it’s a calmer moment in an otherwise busy garden, and again it plays with levels.

Does it all sound like a tempting garden? If so, you can find it in the National Gardens Scheme’s Yellow Book. Go along and talk to Gordon about it – unless of course he’s already taken off to enjoy his prize, a ten-day trip for two to Australia.

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