Tufted vetch seed pods are at the peak of ripeness right now, beginning of Sept. Easy to find in the hedgerows, with the last beautiful bright blue flowers still showing - just shake the stems and the seed pods will rattle, telling you where they are.
Valerian, common hemp nettle, marsh and hedge woundwort heads are full of seeds, and the last few meadow vetchling and bush vetch seed pods are still to be found. Hemp agrimony flowers just beginning to go over and greater birds foot trefoil pods are fattening and blackening up, seeds will be ready in a couple of weeks, and loosestrife seeds will be ready at around the end of the month.