Gardening: I'm dreaming of a white potato: Anna Pavord goes north to Scotland where she delights in the combination of order and profusion in a classic kitchen garden

SHEEP have never been any good to me as encouragers of sleep. I see them jumping over hedges straight into my flower beds, as they have done for real so many times in the past. Instead of drowsing, I beat the duvet in ancient rage.

Kitchen gardens are my narcotic. I work through neat, parallel rows of onions, carrots and leeks. My inner eye wanders over walls trained with perfect espalier apples and pears. Only on nights of acute insomnia do I need to get inside imaginary glasshouses and start counting the bunches of grapes on the symmetrically tied-in vine.

Order coupled with profusion, and a sense of being cut off from the real world are the hallmarks of the best kitchen gardens. You have to have walls for that sense of detachment. Whether made of brick or stone is immaterial. Brick is easier in that the courses are straight, which helps when you are fixing wires for your trained fruit trees.

The trees are another necessity: fans on the walls, old espaliers making screens along some of the paths. It is as much for the geometry as the crops. And the blossom in spring, with the sound of bees fumbling and falling about in the flowers like overweight curates on a picnic.

Scotland is the place to see good kitchen gardens. This is partly because of the way that gardens have evolved there: pleasure grounds and policies around the house, kitchen gardens usually some way away and cunningly arranged to give fruit and vegetables the best start in often bitter weather.

One of my favourites is at Glenbervie House, Mrs Macphie's garden at Drumlithie, Stonehaven. The walled garden there is set on a south-facing slope with an astonishing range of decorative old glasshouses stretching the length of the sunniest wall.

The centre section is a semicircular bow arranged inside with tier upon tier of wooden staging on which, in the old style, the gardeners arrange hundreds of plants in clay pots. Outside, there are whole borders of flowers for picking and wide paths lined with swags of roses.

Earlier this month, I was again in the Kincardine and Deeside area and went to visit the kitchen garden at Douneside House, Tarland. This is not as grand or as established as Glenbervie but it has all the necessary requisites of a good kitchen garden: seclusion, order, fruitfulness.

Douneside, once a simple, low farmhouse with a spectacular view of the Deeside hills, was aggrandised by the MacRobert family in the first years of this century. I went round the garden with Albert Paterson, who has been working there for 20 years, and Peter Jamieson, who has been around for 10.

Potatoes are Albert's thing. (And Charollais cattle. He has a 12-acre croft where he introduced the first Charollais ever seen in this area.) He had just started lifting some of the 12 different varieties of potato that they grow at Douneside.

His favourite is Catriona, a second early with white, floury flesh. It is a good potato for exposed situations because the foliage does not grow as tall as other varieties. It also dies down early, so usually misses the blight that can be a problem in damp areas of the country.

Albert brought out a basket of prize specimens freshly dug. Peter weighed one on the scales in the bothy. It made more than two pounds. We gazed reverently at the long, flattish cream tuber with smudgy purple eyes. 'A fine potato,' said Peter. 'Aye,' said Albert.

The kitchen garden here is on a slope, with a lean-to glasshouse against the south wall and a wide path leading through the middle. At the centre of the garden is a circular raised pool and small fountain, surrounded by a neatly clipped hedge. The path leads on down to white-painted gates that give on to the main part of the garden, with clipped topiary in the shape of square whisky decanters either side of the gates.

One large square was given over to strawberries, Elsanta and Cambridge Late Pine, the latter by far the superior in terms of flavour, says Albert, though not as vigorous in growth. They have recently started using a woven black polypropylene material under the strawberries, which keeps weeds down and means they don't have to bother with spreading straw around the plants to keep the fruits clean.

I tried the same stuff last season ( pounds 17.95 for a roll 6.5ft wide, 20ft long from Agriframes). You have to stretch it over the ground, and then plant the strawberries in holes cut into it. I fixed mine by burying the edges under the earth. At Douneside they had a neater solution. They had wound the two ends round heavy timber planks which kept the material much more taut. A few stones weighed down the side edges.

The problem if the material is not taut, as I found, is that wind gets under the material and keeps lifting it up and over the plants which then languish under this dark muffler.

You have to prepare the ground well before you cover it and, especially for strawberries which are greedy plants, dig in plenty of muck. Once the sheet is in place, you cannot get any more muck into the ground. That is a slight disadvantage, as at Douneside they usually muck the strawberries liberally every year. They think they can compensate by liquid feeding during the growing season. In materials, this is all more expensive than the old methods, but you save on labour.

Albert was even more enthusiastic about the spun polypropylene fleece which they used for the first time this year. You see it stretched in vast quantities over the rich land of the Fens, where it protects early potatoes against frost.

It is translucent and also permeable to rain, but not to insects. It foxed the carrot fly, which has been a long-standing problem in the Douneside garden. The fleece was laid over the rows of carrots early in the season and stayed there until harvest. It gave a similar boost to the parsley, the parsnips and was also used to keep caterpillars off the cabbages. Agriframes sell it at pounds 9.95 for a roll 40ft by 5ft.

The old glasshouses at Douneside are relatively modest, but beautifully organised, with a vine trained along the struts of the roof and pots of pelargoniums, begonias and other ornamentals massed on shelves against the wall.

Tomatoes take up most of the rest of the space. They don't thrive outside here, so the whole crop is grown in the glasshouse. Glass has always been important in Scotland to provide protection and extend the growing season.

The great wonder in Victorian times was the glass fruit house at Drumlanrig Castle in Dumfries. It was about 500ft long and 18ft wide. A cast-metal path ran down the middle with the edges raised to make tracks for a railway wagon that was used to cart muck in and produce out.

In the 1880s, the house was packed with nectarines and figs, peaches, pears and plums all trained up wires strung from the roof. Fourteen gardeners worked there for the Duke of Buccleuch under David Thomson, one of the best gardeners of the day. They founded a mutual improvement association and kept a note of the subjects discussed at their meetings: Forcing of the Fig, Certain Trades and Professions as Causes of Disease, Cultivation of the Raspberry, Man's Inhumanity to Man. I can see Albert Paterson doing well there. An Ode to Catriona perhaps.

For details of open days at Douneside and other Scottish gardens next season, consult 'Scotland's Gardens', the guide to all gardens opening under Scotland's Gardens Scheme. The 1993 guide will be out in February ( pounds 2 plus 50p p&p), from 31 Castle Terrace, Edinburgh EH1 2EL (031 229 1870). For an account of a classic English kitchen garden read 'Cottesbrooke' by Susan Campbell (Century, pounds 14.95). Agriframes are at Charlwoods Road, East Grinstead, West Sussex RH19 2HG (0342 328644).

(Photograph omitted)