As its name suggests, giant hogweed it a large umbellifer with distinctively ridged, hollow stems. An introduced species, it is an invasive weed of riverbanks, where it prevents native species…

Despite its name, Common knotgrass is not a grass, but is actually related to the docks. It has wiry stems that grow along the ground, and is a weed of waste ground, gardens and arable fields.

Groundsel is a 'weed' of cultivated and disturbed ground like field edges, roadside verges and waste ground. It has clusters of yellow flowers that turn fluffy and white as the plant…

A tall plant, Rosebay willowherb is a successful coloniser; it can form dense stands of bright pink flower spikes on disturbed ground, such as woodland clearings, verges and waste ground.

This stocky relative of grasshoppers is found on damp ground close to water.

Toadflax-leaved St John's-wort has star-shaped, bright yellow flowers. It is a rare plant, with most of its population existing on Dartmoor. It likes steep, sunny slopes, acidic soils and…

The subject of much myth and legend, and a herbal remedy, perforate St John's-wort is a familiar flower. It has star-shaped, bright yellow flowers and lots of tiny holes in its leaves that…