Garland's poetry had appeared in John Lehmann's The London Magazine and the annual PEN anthology during his teens.

[10] His appearances as an actor included An Age of Kings, where he played Prince John in Henry IV, Part 2 and Clarence in Richard III, among others.

[11] His work with the BBC arts department included interviews with Noël Coward (1969), Stevie Smith, and Marcel Marceau.

[12] His television film of The Snow Goose (1971) won a Golden Globe for "Best Movie made for TV", and was nominated for both a BAFTA and an Emmy.

In 1967 he created a one-man show based on John Aubrey's Brief Lives with Roy Dotrice (and Michael Williams in a later revival) and the following year directed the original production of Alan Bennett's Forty Years On with John Gielgud as the headmaster of a decaying public school called Albion House.

[citation needed] This production transferred to the Vaudeville Theatre in the Strand London West End in the spring of 1979.

[16] After Garland's death the British Library acquired his archive [17] including diaries and journals, personal and professional correspondencve (including extensive correspondence with Alan Bennett and Ted Hughes), production files, prompt books and directors’ annotated scripts and material relating to Poetry International which Garland founded with Ted Hughes and the inaugural festival at London’s Southbank Centre in 1967.