Fields by Mondrian, cut and dried: Parts of the Kent countryside are newly cultivated in a colourful array of hops, grasses and exotic flowers. Anna Pavord meets a couple reaping the benefits

Farm diversification projects and the EC set-aside policy are having an interesting effect on the English landscape. As a result of the policy, under which farmers are paid a subsidy to take land out of cultivation, there are huge swathes of sky-blue flax where once there was buff corn; patches of red poppies where land is ploughed but no longer sown. It is as though the painter Mondrian had been let loose to work on a monster scale.

There have been fields of sunflowers, too, in the South, bobbing over hedges and waving like those extraordinary toys that were once popular with garages - sunflowers with sunglasses on that jiggled about in time to music.

In Kent, in the region of the Darenth Valley, are even more exotic summer sights: fields full of gypsophila, love-in-a-mist, achillea, sea holly. This is William and Caroline Alexander's diversification project, The Hop Shop: 30 acres on which they grow 70 varieties of flowers and grasses for drying.

It all started with hops, which they had been growing as a crop for the brewing industry. Hops used to be the big thing in Kent, along with apples, but both crops have declined there, overtaken by German lager and French Golden Delicious. As well as selling fresh hops to brewers, Caroline tried selling dried hops to local publicans to decorate their pubs.

This was successful enough to persuade the couple to market dried hops more professionally. They developed a method of drying and packaging, creating 10ft-long swags of hops, wrapped like dry cleaning in polythene with a hanging hook at the top.

In the hop fields, the hop bines grow curling clockwise up long strings supported by poles. The Alexanders cut the bines - string and all - and hung them to dry in farm buildings they converted to drying sheds, filled with the noise of the vast fans blowing hot air.

The swags were a huge success and brought the couple into contact with florists who fell on them like starving men at a wedding feast. Most dried flowers and foliage is imported from the Netherlands. The fact that it could be produced in England was a revelation.

At first, the couple meant to specialise in various wheats, oats and barley for drying, which, as far as farmer William was concerned, would at least be familiar crops. Then they thought they might add a few high-value flowers such as echinops (Globe Thistle). From that modest beginning grew a business of enormous complexity that the Alexanders taught themselves.

The way that a plant behaves in the garden is not always a reliable indicator of how it will grow in field conditions. Love-in-a-mist (snog-in-a-fog, the children unromantically call it) seeds itself in most gardens with a prodigality that makes you think it would be one of the easiest of flowers to grow, but the Alexanders found it difficult to persuade to germinate in the field.

Chinese lantern, Physalis franchetii, is another common plant that usually presents no problems for gardeners. Again, it sulked in the field, seeming not to like being exposed so nakedly to the elements.

Learning what would dry well was easier. Caroline found that if a flower dried well in bunches hung over her Aga, it would dry equally well in the kiln. She does artichokes, sunflowers and maize cobs, as well as the more usual larkspurs, statice and straw flowers.

With all flowers, they learnt that the faster the drying, the better the colour. If they are not dry enough, they go mouldy. The most difficult thing they had to work out was when to pick the flowers. Some only last 24 hours in exactly the right state, others are less critical. With marjoram, for instance, they learnt that it has to be picked in bud. If they pick it when the flower is full out, it discolours while drying.

Lavender responds to the same kind of timing. Honesty, too, dries better if it is picked early, rather than late. The flowers of helichrysum go on developing after they have been picked while they are drying, so they cannot be left long in the field once they start to open.

Statice reacts in the opposite way. It does not develop at all in the kiln and needs weeks of sunshine to coax out its flowers. It discolours badly in rain. Atriplex, which the couple grows for its seedheads, sheds all its seed if picked at the wrong time.

Wheat, which they thought they knew all about, turned out to be as tricky when grown for drying as any of the flowers. If they picked it before the head overtook the flag leaf sheathed round the stem, the overall effect was too leafy. If they left it too long, they lost the greenness that makes their wheat look so fresh and wholesome.

Combine harvesters, of course, were no good for gathering in the crops of wheat. Instead, they imported a rice-cutting machine and adapted it to use when the weather was too wet for hand picking. They make small stooks of their corn, bound with rough, plaited twine - very Country Living.

There was a time when dried flowers meant nothing more than poppy heads and Chinese lanterns jammed in a large jug in the hall. Some arty folk added heads of dried cow parsley and a few drooping stems of oats. Now you bob and weave through kitchens dolled up as if for a Mother's Pride commercial; half a field full of dried flowers hanging from the ceiling. What has brought this about?

Two things happened. The Dutch pioneered a method of kiln drying which meant dried flowers could be produced in huge quantities. And we plunged into a prolonged bout of nostalgia, which produced cottage gardens, farmhouse kitchens, country interiors - even in places that had not seen a cottage, farmhouse or a piece of country for more than a hundred years.

Dried flowers are a part of this business of playing shepherdesses. Or at least dried flowers in bunches are. When you approach dried flowers in arrangements, you are in serious interior decorating territory, and I will leave you there, agonising over the exact shade of xeranthemum to go with the slubbed peach curtains. Caroline Alexander and her staff provide all the help that the most fevered colour co-ordinator could desire.

The Hop Shop at Castle Farm, Shoreham, Sevenoaks, Kent TN14 7UB (0959 523219) is open Mon-Fri (1pm-5pm) and Sat (10am- 5pm). Send four first-class stamps for a list of produce available by mail order. Achillea costs from pounds 2.60- pounds 2.95 a bunch, larkspur pounds 3.25, helichrysum pounds 2.45. Hop bines are available only during September and October.

(Photograph omitted)