The tightly packed, thistle-like purple flower heads of common knapweed bloom on all kinds of grasslands. Also regularly called black knapweed, this plant attracts clouds of butterflies.

The distinctive spiky, or 'bearded', green flower heads of wall barley appear from June to July and are easy to spot in an urban environment as they push their way up through pavements…

The aromatic fragrance of Large thyme can punctuate a summer walk over a chalk grassland. It is an evergreen that grows low to the ground, with erect spikes of tiny, lilac flowers appearing over…

Look for the pinky-white flowers of the dog-rose in summer, and its bright red rosehips in autumn. It is a scrambling shrub of hedgerows, woodlands and grasslands.

As its name suggests, pendulous sedge has drooping form with long, nodding flower spikes that give it an attractive and soft look. It can be found in wet woodlands and along riversides.

A climbing plant of hedgerows and woodlands, Black bryony produces greenish flowers in summer and red, shiny berries in autumn. It is a poisonous plant.

A climbing plant of hedgerows and woodlands, White bryony produces greenish flowers in summer and red, shiny berries in winter. It is a poisonous plant.

Looking like a short dandelion, but with a much rounder middle, colt's-foot is a 'weed' of waste ground and field edges that brightens up early spring with its sunshine-yellow…

The brown, oval flower heads of ribwort plantain balance on top of thin, wiry stems; the resulting seed heads provide food for birds in winter. Look for this 'weed' in lawns, fields and…