Stone in the garden adds character. The details of leaf and flower, the bright colors, the ever-changing shapes ... all show to best advantage beside the solidity, gravity, stability of stone. It's the perfect building material for the infrastructure of the garden: retaining walls, stairs, paths. On these bones, a garden grows a substantial presence.

Here in New England, we learn to live with stone. Like some subterranean crop, rocks heave up from the earth every winter. Tumbledown old walls, made simply by piling rocks up, line roads and fencerows — even in deep woods, where land once farmed has reverted.

The foundations of my hundred-year old house are granite blocks up to nine feet long — quarried not far away, I am sure, in those days. My daughter's house sits on ledge that bulges into the front of the basement, and rises aboveground in the front yard. Grass won't grow in the thin soil in its crevices; instead she has a distinctive collection of lichen and succulents.

Rocks also make good mulch, keeping the soil cool and moist. And even if you don't have a handy ledge in your yard, an occasional interesting piece can be added for architectural interest.

My friend Richard, who lives on a street of new houses, spotted a likely stone in the unfinished yard next door. A professional was landscaping most of the yards, but Richard was doing his own. In order to make lawns, the landscaper was removing all the rocks turned up in construction.

The granite boulder Richard wanted was roughly four feet by three, by two and a half. He spent over an hour, grunting and sweating, to maneuver it: shifting and levering and rolling it, until it was on his property — and he was on his knees, totally exhausted. But what a beauty he had rescued!

In the morning, on his way to work, he admired it again. What a great centerpiece it would make for the yard.... When he got home from work, it was gone.

He rushed next door. The site manager had noticed the rock's migration, assumed the landscaper had been sloppy, and angrily ordered him to get rid of it before Richard complained they'd trashed his yard.

Richard did end up with an accent stone for his garden, but it's a fifth the size of the one that got away.

Where do I get stone for the garden? I've collected rock from all kinds of places; the best are where the earth is disturbed, like construction sites — but I always notice interesting rocks beside the road, and am not shy about knocking on doors to ask whose land it is, and whether I can use them for my garden.

But there are also places you can buy stone. Next week I'll describe my favorite.