Balm / Lemon Balm
Spikes of small whitish-yellow flowers, 2-lipped, in auxillary whorls. Seeds freely, can be persistent. Toothed, stalked leaves, lemon-scented, slightly hairy above. Erect, branched stems. Height: Can reach 1m+, but usually less.
Culinary herb, known to gardeners as Lemon Balm.
Roadsides, waste ground, hedges, river banks. Increasingly recorded garden escape or discard, also relic of cultivation.