Country & Garden: I'm going back to my roots

Anna Pavord In The Garden: From an old-fashioned potager to a hi-tech vegetable production line, kitchen gardens provide balm for the soul

A row of parsnips or red cabbages, growing well and heartily, gives me as much pleasure as any confection of old roses. When visiting gardens, I am always drawn to those in which vegetables have a place. However beautiful, a garden with nothing to eat in it always leaves me feeling hungry: too much icing and not enough cake.

So, although deeply impressed by the great rising bank of pinks and purples and blues that met me at Susan Brooke's garden, Overstroud Cottage, the potager that she has made on the top level was the clincher. Tucked into a triangle made by two boundary walls, it has the serene, peaceful air of all productive vegetable patches. The third long arm of the enclosure is provided by a row of low, stepover apples - "Jester", "Bountiful" and "Jupiter".

Winding through the potager are stepping-stones stitched together with patches of camomile and creeping thyme. With each step you release a slightly different cocktail of scents: sometimes more thyme, less camomile, sometimes the other way around. Sometimes a touch of sage or curry plant adds itself to the mix, as you brush by it.

You paint different pictures when you garden with vegetables, but they can be as beautiful as any flower-filled scenes. The frame is important and Susan Brooke's potager benefits from its high retaining walls, planted with pears and plums. The enclosed triangle gives her an interesting shape to plant in: patches of bronze lettuce, tall black "Cavolo Nero" kale, rising like Prince of Wales's feathers from clouds of purple mint.

She has beet, Italian chicory and violas between the pak choi, and purple podded beans growing up black bamboo canes. Why black bamboo? Because when you look at the potager from other parts of the garden, the black disappears into the backdrop. Instead of looking at a forest of canes and supports, you see only the plants.

Aura, atmosphere, soul, spirit, solace, healing are words that Mrs Brooke uses constantly in connection with her garden. The way that it feels is intimately wound up with the way that it looks, and the Brookes have been here long enough (18 years) for the place to feel all of a piece. There is a strong guiding hand here.

"All Susan's work," said her husband Jonathan, speeding through the kitchen. "I just pay the bills."

It's not a big garden, but it is steep, with the Brookes' Gothic cottage sitting high up on a bank and the garden falling away in front of it. Behind are hanging woods, which rise with equal steepness. The underpinning is chalk, carved into two levels. Moving from entrance gate to front door, you seem almost to swim between waves of dark astrantia, smudgy purple poppies and yellow day lilies, shining out against mounds of almost black Geranium phaeum. There are masses of roses, too: dark "William Lobb" with mossy buds, "Kew Rambler" smothering a shed, and pink "Frances Lester" sprawling into an apple tree.

Where there aren't roses in this garden, you will find clematis, intertwined with honeysuckle on arches, underplanted with valerian, alliums and fluffy clouds of thalictrum. The colour is carefully controlled. "I like soft colours," says Mrs Brooke. "They create an aura of calmness."

The cottage faces south-west, a perfect aspect for the pears planted on its front. On the same level is the little studio where Susan Brooke paints or works on garden plans.

Before you ever found the studio, though, you would guess that an artistic eye was overseeing the garden at Overstroud Cottage. This is all part of the intrigue of visiting gardens: guessing the motives and make-up of the various owners.

For instance, when I pulled up at South Farm, Shingay, in Cambridgeshire, this week, my instinct was that this was a man's rather than a woman's garden and that here, techniques of growing were at least as important as the finished result. Philip Paxman, the owner, is a vet - not the James Herriot kind, but a biotechnology whiz. At South Farm he is building his own sustainable bubble. There are egg-laying Chinese geese in the farmyard. There are fish in the ponds. In the series of vegetable gardens behind the farmyard buildings; there are more different kinds of things to eat than I have ever seen in one place before.

At South Farm, though, The Good Life is crossed with the Cambridge Science Park. Pinned to the door of an ancient lean-to was a sign saying "Irrigation controls". Inside, computers clicked and hummed, pressure vessels gleamed, a timetable showed the various zones in the garden and when they were to receive their water. It was mesmerising. I insisted on a guided tour, not of the garden but of the irrigation system.

It all depends on an artesian well, sunk last year to a depth of 165ft and capable of delivering 700 gallons of water an hour. That cost pounds 7,000, but given that the average rainfall here is only 19in a year, he needed a secure source of water to sustain his phenomenal production line of fruit and veg. The watering equipment cost another pounds 3,000, but that includes toys such as sprinklers that, at a touch of a button, nose up like snouty worms out of the lawn.

"Oh, it's just playing, really," said Mr Paxman, but it's not. His tool sheds tell you that he is an organised, practical man. Down the centre of one of the polytunnels runs a hot bed, built up with layers of manure, sawdust and grass clippings. "Poor man's greenhouse," he said, waving at the tunnel. "Good solar collector in the day. Heats up like mad. But radiates out at night. Big differential. Very shocking for plants."

The hot bed, kicked into glowing mode by ammonium sulphate, is covered with bubblewrap during the day, then uncovered at night, when it acts like a massive storage heater, gently releasing warmth into the surrounding air. In summer, the hot bed is used for edible gourds and squashes, trained up trellis panels.

Now Mr Paxman is into sewage. He's dug up a large part of his paddock to make a reed bed: effluent in at one end, drinking water out at the other. That, anyway, is the dream. "Difficult to get good info," he mused, gazing at the puny stalks of reed that were fighting to establish themselves in the rafts of straw.

"Flow rate must equate to the volume of effluent. If there is too much, it goes through too quickly. And then, you see, you have to match the size of the bed to the numbers in the house. Mine will cope with 16 people." It's awesome. Don't miss it.

Overstroud Cottage, Frith Hill, Buckinghamshire, is open tomorrow (2pm- 6pm), admission pounds 1.50. Turn east off the A413 at Great Missenden on to the B485 to Chesham. The white-painted cottage is set back on the left, in a lay-by 100 yards up the hill. South Farm, Shingay, Cambs is one of three Shingay gardens open tomorrow (2pm-6pm), combined admission pounds 2.50. Teas and parking are available at South Farm