Green Bullfrog is a blues album recorded by an ad hoc band and produced by Derek Lawrence. The bulk of the album was recorded over two sessions at De Lane Lea Studios, London in 1970, with later string and brass overdubs. It was originally released in 1971, with reissues in 1980 and 1991.
The album listed pseudonyms in the credits for contractual reasons and was commercially unsuccessful. The musicians were eventually confirmed as including Deep Purple's Ritchie Blackmore and Ian Paice, Procol Harum's Matthew Fisher, Chas & Dave's Chas Hodges and session guitarists Albert Lee and Big Jim Sullivan.
Background
thumb|left|upright|[[Deep Purple's Ritchie Blackmore attended the two Green Bullfrog sessions.]]
Green Bullfrog was the idea of producer Derek Lawrence, who assembled a group of musicians with whom he had worked in the 1960s. Guitarist Albert Lee had been working with Lawrence as a session player, and the original idea had been to record with former Screaming Lord Sutch bassist Tony Dangerfield. However, the sessions did not work out, so the pair decided to invite other session musicians and Sutch alumni and record a studio jam.
The backing tracks were recorded in two overnight sessions on 20 April and 23 May 1970 at De Lane Lea Studios, London, starting at 11pm. All the musicians had wanted to play together for some time, but were too busy with touring or session work to do so. Singer Earl Jordan had been recording with the Les Humphries Singers. He put down guide vocals during the main session, then re-recorded all his parts after everyone else had left.