Solid foundations: From marble to meteor stones, a great gravel merchant should have the pick of the rock

(GETTY IMAGES)

The star of my gardening year is J C Phillips & Son Ltd, a sand and gravel merchant in whose yard I have spent an inordinate amount of time over the past 12 months. Josiah Charles himself is long gone, and the place is now owned by David Weston. He first started work at Seatown, just off the western edge of the great Chesil Bank in Dorset, handpicking pebbles from the beach which were then used to grind talcum powder, paint and Ajax. "It sounds worse than Dickens," I said. "No. It was great," he said. "Crouching down with the bucket between your knees. The pebbles had to be just right. Perfectly round. No holes in them."

So here's a man for whom pebbles are as diverse and intriguing as flowers are to me. His yard is a geological map gone mad: Cotswold next to Caledonian, golden Spey quartzite next to slivers of Welsh slate. "Slate," he says impassively. "Landscape gardeners love it." But I grew up with slate, wet roofs in Wales, dour Victorian architecture, dark, absorbent colours. Slate is functional but tedious, with none of the gorgeous variation in colour you get with pea gravel.

I'm not mad either about that other landscaping favourite, Cotswold gravel, plain, pale cream, as glaring in hot weather as the sands of the Kalahari. Outside its natural home Gloucestershire, Oxfordshire it draws unnecessary attention to itself, fights with local materials that may be greyer or more gingery in tone. In principle, I'm for using local materials wherever possible. The problem is, it's often not possible. As Ian McEwan found to his cost, stones can no longer be carted off Chesil beach and anyone in our patch of West Dorset looking for pebbles or gravel to fit with the particular brindled look of the local stone has now to buy stuff trucked in from an inland quarry in Norfolk.

"Gardeners want all natural materials now," says David Weston, who has seen a huge increase in business from people like me. When he first started at J C Phillips more than 20 years ago, gravel for aquariums and filtering water was the firm's main line, a niche market that is still an important part of what they do. But nobody then wanted Highland glacial cobbles (lovely big rounded stones in quartzy greys, the kind you see in the rivers of Wester Ross), Pentland paddlestones or cratered meteor stone.

I gazed for a long time at the meteor stone when I first came across it, wondering what use I could find for it that wouldn't look too obvious. It's a good colour for our area soft creamy brown, the colour of home-baked shortbread and the huge lumps are drilled through with holes like a series of parallel railway tunnels. The boring has been done naturally, of course, and the effect is extraordinary. Sempervivums would love it, if they could get their roots down into soil sifted into the bore holes. But where to put it?

Newly arrived at J C Phillips are rectangular stone troughs, handsome things brought in from China. The biggest are six feet long, massively difficult to move. David Weston got a call recently from a customer who had bought one; now she was moving house and wanted him to move the trough with her. So he took a crane and shifted the whole thing, fully planted up, with scarcely the loss of a leaf. That's another reason this yard is a star. They actually like their customers, which is a rare treat. If you ask them to deliver, which given the nature of their trade they usually have to do, the stuff is with you the following day.

"Except round Easter," says Mr Weston's wife, Rachael, quickly. "That week is always manic." She's the one who, with their daughter, Sarah, mans the phones in the mobile office, tucked in behind the huge old semicircular aircraft hangar that houses the dumper trucks, the vast mixing machines and hoppers that this business requires. They reckon there are not many materials that they can't find somewhere, though they are temporarily stumped by a customer who, back from a holiday in Lanzarote, wants to landscape her garden in Lanzarote-style black volcanic rock.

Outside the hanger are mountains of sand brought from Dorchester, Swanage and Devon. "Different colours," explains David. Huge pallets are stacked with cages of Scottish Highland pebbles. They were the things I swooped on to make "rugs" in the mostly brick terrace in front of our house. You can get them in six different sizes from 4-8mm up to 80-120mm. If you use just the same basic material, but vary the sizes, you can get interesting effects on a path or terrace. The cobbles need to be properly set in sand. Ours are mortared as well.

From the Highlands, too, come J C Phillips' cobbles and boulders, ringed round like swirly ice cream with wonderful soft greys and creams. These start at about 100-200m and go up to a metre across. Used carefully, they are perfect for the "dry riverbed" look, or for creating a kind of beach at the edge of a pond, where they usefully disguise the hideous plastic liners that ponds seem to require.

You can get Alba marble there (too much like gravegoods for me) and softly polished pebbles in yellow, black, or red. You can buy flat paddlestones from Strathisla or rockery stone in Balmoral grey, Grampian pink or Skye marble. Chippings (they've got hard edges, unlike the pebbles) come in an extraordinary range of colours: Iona green marble, Ardownie black whinstone, Buchan pink granite. If you are wall building they can provide orangey Ham stone, greyish Purbeck or forest marble from Stalbridge. The possibilities are rivetting but the important thing is not to use too many different materials in a single small space.

Over the last year or so, we've used their 10mm gravel to surface the yard and a large quantity of very nice brindled pea gravel to fill in between the risers of our railway sleeper steps. But this autumn I've mostly been calling in for fine gravel, "six mill clean" as I've learnt to call it. That means that the stuff has been through the great washing machine in the hanger and is pure grit, rather than grit and sand mixed. The mixed stuff is called "all in". I've been bulb planting on a massive scale, mostly in pots. Drainage is one of the chief keys to success, so the bulbs go in a mix made from one part of the fine gravel and two parts of John Innes No3 compost. I top off the pots with gravel too. It looks good, stops blackbirds chucking the compost about and keeps the flowers clean when they first break through into the light. And the gravel comes in 25kg bags, which means that with the help of my Draper sack truck (last season's Star of the Year) I can haul them easily to the workshop. Perhaps by next year I'll have cracked the conundrum of the cratered meteor stone.

J C Phillips & Son Ltd are at 162A South Street, Bridport, Dorset DT6 3NP, 01308 422179. Open Mon-Fri (8am-1pm; 2-5.30pm), Sat (8am-1pm)