He began a reading career on Edinburgh Festival fringe in 1960, with the London poets Pete Brown, Mike Horovitz and Libby Houston.
Jackson went on from this time till the early 1970s to give hundreds of readings throughout Britain, often solo, but mostly with Patten, Mitchell, Morgan, Houston and others of the poets mentioned above.
Heart of the Sun (published in 1986 by Open Township) has a long introduction entitled "Reasons for the Work", describing his poetic evolution through the years since the decision to "retire".
Jackson had always had considerable philosophical and historical interests and a main feature of the introduction is his account of how experiences of his own led him to the work of Rudolf Steiner, the Austrian Christian initiate.
In June 1971 the whole issue of Lines Review 37, the Scottish literary magazine, was devoted to Jackson's essay "The Knitted Claymore", which expressed his conviction that rising nationalist sentiment in Scotland was infiltrating and distorting the realm of literature.