I enjoy walking on the urban margins. This stretch of the River Purwell on the outskirts of Hitchin runs past an industrial estate, under a railway bridge then meanders between a sewage works and a scrapyard. None the less these fringes which are neither town nor country are a haven for nature.

 As I approached the bridge I saw something gleaming yellow in the foreground: a cluster of Primroses (Primula vulgaris), the first ones I've seen in flower this year...