Considered to be one of the prettiest gentians, the Chiltern gentian is a rare plant in the UK. It likes chalk grasslands, its purple, trumpet-shaped flowers blooming from August.

The early gentian is a rare plant that is only found in the UK. It likes sunny, lowland chalk grasslands, its purple, trumpet-shaped flowers blooming in May and June.

The striking black-and-white checks of the marbled white are unmistakeable. Watch out for it alighting on purple flowers, such as field scabious, on chalk and limestone grasslands and along…

Meadow buttercup is a tall and stately buttercup, with buttery-yellow flowers that pepper meadows, pastures, gardens and parks with little drops of sunshine.

As its name suggests, the Dwarf thistle is a low-growing plant that is almost stemless - its purple, thistle-like flower heads growing out of a rosette of spiny leaves.

With a silvery body, and purple, pink and bluish streaks down its flanks, the rainbow trout lives up to its name. Popular with anglers, it is actually an introduced species in the UK.

Bittersweet is a nightshade, so is toxic; its bright red berries may be tempting, but can cause serious illness. Found in hedgerows and gardens, it has purple flowers with yellow stamens.

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.

Eyebright has small, white flowers with purple veins and yellow centres. It likes short grasslands, from clifftops to heaths, and is one of a number of species and hybrids that are hard to tell…