Vaughan Williams played the viola, and frequently professed it was his favorite instrument. Along with the Suite for viola and orchestra of 1934, his most significant work for the instrument is the unusual Flos Campi (Flower of the Field), which combines the viola with a spare orchestral backing of strings, winds, tabor, and celesta, along with a mixed choir that sings wordlessly. It was first performed on October 10, 1925, in London, with violist Lionel Tertis, voices from the Royal College of Music, and the Queen's Hall Orchestra conducted by Sir Henry Wood. The reaction was mixed, and even such close friends of the composer as Gustav Holst admitted themselves puzzled by this subtle and voluptuous work.
In a program note for a 1927 performance, Vaughan Williams admitted "The title Flos Campi was taken by some to connote an atmosphere of 'buttercups and daisies....'" This is, in fact, far from the atmosphere of this work. Each of its six movements is headed by a quotation from the Old Testament's Song of Solomon, and it is the passionate quality of that text which informs Flos Campi. The work opens with the juxtaposition of viola and oboe, both playing melodically but in different keys, creating palpable tension. This opening movement is languorous and mysterious, its associated text speaking of the sickness of love, of how it is a "lily among thorns." Nature springs to life in the second movement, with the "singing of birds" and the "voice of the turtle." But the beloved is not present, and the third movement is passionate and agitated, with the viola accompanied mostly by the women of the choir. Men "expert in war" are at Solomon's bed in the vigorous fourth-movement march, in which the violist has an opportunity for some virtuoso display. The music builds to a rather tense climax, at which point we hear the murmuring of voices, over which the viola soars longingly. The orchestra takes up this music in a more peaceful strain, and the choir sings in sweet polyphony. The opening viola-oboe duet returns, but its ambivalence is resolved as the melodic material of the fifth movement is taken up again in a quiet and magical coda.