Selfheal is a low-growing, creeping plant that likes the short turf of grasslands, roadside verges or even lawns. Its clusters of violet flowers appear in summer.

Common couch is a tall, tuft-forming grass of roadside verges, waste ground and arable land. It is very tough and can shade out more delicate plants. Look for flat, blade-like leaves and thin…

As the name suggests, the Common medium stonefly is found in gravelly upland rivers and streams, often on bankside stones and plants. There are 34 species of Stonefly in the UK, which are hard to…

Often seen carpeting the floor of ancient woodlands, Dog's mercury can quickly colonise, its fresh green leaves shading out rarer plants. It is also very poisonous.