Sir Peter Maxwell Davies was 80 on 8 September. The Scottish Chamber Orchestra, with whom he has been closely associated since the 1980s, when he became its composer/conductor-in-residence, gave him two special birthday presents: one was a snazzy waistcoat, made from the tartan that the orchestra commissioned to mark its own 40th anniversary; the other was a late-night celebratory programme at the Proms, devoted entirely to his works, and conducted by Ben Gernon.

Its centrepiece was the fourth of the set of 10 Strathclyde Concertos that Davies composed for the SCO and its principals between 1986 and 1996. It’s a half-hour single-movement work for clarinet; the soloist here was Dimitri Ashkenazy, who emphasised its collaborative rather than confrontational character. The music lingeringly searches for an ancient pibroch melody, which the clarinet eventually discovers, in Davies’s own beautifully tailored version, in the closing pages of the concerto. Before that arrives, though, there is plenty of taxing solo writing – especially in a main allegro section haunted by Scotch-snap rhythms – as well as a rather wistful slow section, both managed with suave ease by Ashkenazy.

Celebratory pieces flanked the concerto. An Orkney Wedding, with Sunrise, Davies’s depiction of a tipsy marriage party on Hoy, where he used to live, was the perfect way for the evening to end, with Robert Jordan’s bagpipes adding the final exuberant touch. The London premiere of the concert overture Ebb of Winter, had begun things; Davies composed it last year, to mark the SCO’s 40th birthday, but it’s a substantial, introspective and hauntingly beautiful piece, a depiction of the first stirrings of spring in Orkney, with lonely instrumental solos wandering through chilly landscapes and a sense of optimism peeking through the closing bars.

• On iPlayer until 7 October. The Proms continue until 13 September.