I thought this was a Swallow-Tailed Moth, but then I realised that the stripes weren’t right. The Blood Vein is a moth – easy ways to tell are that it rests with its wings outstretched and it has feathery antennae (not shown). The Blood Vein is a sort of buff colour with a russet stripe that looks continuous through all four wings and russet edges to its swallowtail shaped wings. They live in damp habitats including wet meadows, ditches, hedgerows, and gardens. Their caterpillars feed on docks, Common Sorrel, and Knotgrass. We definitely have dock and sorrel in our patch.
Also, in the picture are Cleaver ‘sticky buds’.