If you come to Bishopstock, you'd better love the blues. For three days, ticket holders can wallow in slow blues, fast blues, electric and acoustic blues, and blues from both rural and urban traditions. This doesn't quite explain how Steve Earle and the Dukes, playing beefy rock'n'roll and country music, came to be topping the bill on Saturday night, but then again his new album is called Transcendental Blues.

The festival takes place in the grounds of Bishops Court Palace adjoining the Devon village of Clyst St Mary. The house dates back to the 13th century, though layers of subsequent upgrades have imbued it with a Fall of the House of Usher-ish air, and its owner, Helen Myers, hosts the festival merely because she adores the blues. Capacity is a mere 5,000, which means punters can enjoy an unusually civilised environment (including homemade ice cream). How close the event comes to covering costs is anybody's guess.

This was Bishopstock's fourth year, and the bill was a mix of reliable crowd-pullers (notably Earle, Taj Mahal and Sunday's headliner Van Morrison) and an array of acts with cultish followings of their own. Mavis "Mother Soul" Staples was left shouldering a large chunk of the Saturday bill after both Jonny Lang and Booker T Jones failed to turn up, and Mavis offered a crafty demonstration of how the veteran performer can delegate most of the work to her band while dropping in a few trademark wails at strategic intervals.

Pouring rain and plummeting temperatures made Saturday something of an endurance test, but the weather improved for Sunday, though it was still too chilly for The Blind Boys of Alabama. The Boys had arrived a day late, but this hadn't disturbed their aura of spiritual calm, expressed though their close-harmony gospel singing and a version of If I Had a Hammer featuring vigorous pogoing. Later, the Fabulous Thunderbirds (resembling a gang of Chicano low riders) plugged in for a barrage of power-blues and an extended harmonica onslaught by band leader Kim Wilson.

But I reckon the best value on offer at Bishopstock was the Blues Workshop tent, where you could pick up tips on finger-picking, guitar tunings and harmonica technique from bluesman Michael Roach and friends. Maybe this was the breeding ground for next year's bill.