Water-cress has become so popular as a salad addition that it is now cultivated on a wide scale. In the wild, it grows in shallow, fast-flowing streams and is an indicator of clean water.

Water-soldier grows submerged in ponds and open water, and pops up over summer, looking like the top of a pineapple! This rare plant displays white flowers and shelters many aquatic insects.

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…

Look for the White water-lily in still and slow-moving water, such as ponds, ditches, lakes and canals. Its lily pads and massive, white flowers float at the water's surface.

Look for the Yellow water-lily in still and slow-moving water, such as ponds, ditches, lakes and canals. Its lily pads and cupped, yellow flowers float at the water's surface.

Found in ponds and marshes, the fragile look of the common water-measurer belies its fierce nature. A predator of small insects, it uses the vibrations of the water's surface to locate its…

The long-winged conehead is so-named for the angled shape of its head. It can be found in grasslands, heaths and woodland rides throughout summer.

A short, but pretty plant of unimproved grasslands, the Green-winged orchid gets its name from the green veins in the 'hood' of its flowers. Look for it in May and June.

Look out for the feathery leaves of Spiked water-milfoil just below the surface of streams, ditches, lakes and ponds; its red flowers emerge from the water in summer. It provides shelter for a…