The butterwort is a perennial carnivorous plant.

It has oblong leaves arranged in a basal rosette, thick and very glandular. These leaves are very sticky and the plant uses them to lure, trap and digest the insects; in this way the plant can obtain all the nutrition needed.

Its roots are very thin and white and serve only to anchor the plant to the ground and to absorb moisture.

The flowers are solitary, the corolla is small and purple with lobes of the lower lip flat and not overlapping.

It is common in bogs and fens (swamps).

In the past the butterwort leaves were used to curdle milk to form a buttermilk-like fermented milk product.

The botanical name is Pinguicula vulgaris while the Irish one is Leith uisce.