Field Wormwood Artemisia campestris
A very rare native which in the UK is found only in Breckland. It flowers from August to September and grows to 75cm in height, usually forming a many-branched clump. Its leaves are silvery green, very finely cut into linear segments. Image: Natural England / Peter Wakely (Flickr).
Find out more: iNaturalist, Online Atlas of the British and Irish Flora, Flora of East Anglia ID guide, Back from the Brink (pdf)