Frost’s painting from the early 1950s sits at the very centre of the debate between the experience-influence abstracted images of the St Ives painters and the theoretical, rigorously constructivist work of his Camberwell contemporary Victor Pasmore and friend, former Slade pupil, Adrian Heath. As such, Frost’s work from this period has a crucial place in British abstract art of the immediate post-war period.
Frost sought to find a visual language which would express in an abstract idiom the sense of place and movement found in the harbour of St Ives. In the group of works to which Blue Harbour belongs, sophisticated geometrical relationships are used to suggest familiar forms and shapes whilst never actually offering us identifiable references. These paintings also see the earliest appearances of what was to become the standard vocabulary of Frost’s art: the semi-circles, the highlighted discs and the truncated 'L' and 'T' forms.
The paintings from this period are also distinctive in their use of colour, each having one overall dominant palette. In Blue Harbour the masterly use of bright ultramarine and other shades of blue suggests boats at anchor and the incoming tide to create an image of great power and impact.
Frost commented on the inspiration for his paintings of this period 'In answering the question 'Why do I paint as I do?' ... the most significant and the simplest approach is by way of example: I have recently competed a 'blue movement' painting. I had spent a number of evenings looking out over the harbour at St Ives in Cornwall. Although I had been observing a multiplicity of movement during those evenings, they all evoked a common emotion or mood - a state of delight in front of nature. On one particular blue twilit evening, I was watching what I can only describe as a synthesis of movement and counter-movement. This is to say the rise and fall of the boats, the space drawing of the masthead, the opposing movements of the incoming seas and outblowing offshore wind - all this plus the predominant feel of blue in the evening and the static brown of the foreshore generated an emotional state which was to find expression in the painting ... I was trying to give expression to my total experience of that particular evening. I was not portraying the boats, the sand, the horizon or any other subject-matter, but concentrating on the emotion engendered by what I saw. The subject-matter is in fact the sensation evoked by the movements and the colour in the harbour. What I have painted is an arrangement of form and colour which evokes for me a similar feeling' (see L. Alloway (ed.), Nine Abstract Artists, their work and theory, 1954, quoted in E. Knowles (ed.), Terry Frost, Aldershot, 1994, p. 60).