Dewstow House

In 1910 or thereabouts, when Henry Oakley emerged from the front door of his comfortable, if unspectacular home overlooking the Severn estuary near Caerwent, he could look out over well-kept lawns, specimen conifers, and sinuous paths exploring the five ponds fed by a system of rills and waterfalls. Or he could turn right round the corner of the façade, to lead his guests to the croquet lawn and on to the Victorian stumpery, in which the dead remains of ancient trees were artfully disposed amongst lush greenery, often upside-down to display the roots. Or he could lead them onward to the carefully tended alpine garden overlooking a pond set about with huge blocks of stone.

But it is even more pleasing to imagine him nipping out of the house in the drizzle and rounding the corner to almost immediately disappear from view down an inconspicuous flight of stone steps let into the bank above the croquet lawn. A newcomer following in his steps would have been astounded to find himself in a rock tunnel, lit hazily by small overhead skylights, and facing a gothic wooden door.

Pushing the door ajar and penetrating further into the gloom he would have been unable to resist the lure of the unknown, a rock-hewn but strangely smooth and alluring tunnel with irregular, platey bedrock slabs making up an even floor. After some 15 yards the passage opens and the visitor finds himself in an underground grotto, its damp walls covered with liverworts and mosses, and the margin of a pool lushly planted with exotic ferns.

Another longer dark passage leads out from this chamber, and opens out into a second ferny grotto in which a curtain of water streams down a screen of tufa to the rocks below. Perhaps he has yet to encounter his host, and presses on courageously. Two dark tunnels beckon, probably he will meet Henry Oakley again in one or other the large tropical glasshouses which were barely visible from the house.

All this and more (for another tunnel on the other side of the house takes a switchback course to a roofless sunken garden on the edge of the lawn) was the creation of the celebrated Victorian rockwork firm of James Pulham & Son.

The tunnels are built in brick, carefully lined and sculpted in cement to deceive even the amateur geologist, for the details of bedding and small faults, angular breaking planes and well worn pathways are meticulously reproduced. The chain of ponds too, are the Pulhams' work, with native stone artfully combined with naturalistic channels fashioned in cement.

Taken together Henry Oakley’s garden must have had the dazzling impact of an afternoon at the Chelsea Flower Show, so many different horticultural specialisms on display in the confines of what could have been a very ordinary garden. What marks this out from so many historic gardens is the pure horticultural enthusiasm of a modestly wealthy bachelor. Most famous gardens come with famous houses, at Dewstow this is not the case.

This probably explains the extraordinary accident by which the gardens of Dewstow were lost. Following Oakley’s death in 1940 and the deprivations of the Second World War, the ponds and tunnels were roughly filled in and the garden reverted to pasture with a few good trees. The Harris family purchased Dewstow House in 2000, unaware, but for the crumbling remains of two glasshouses, of what lay concealed.