Sneezewort - Achillea Ptarmica
This is a plant found in damp or wet habitats, on a wide range of neutral to slightly acid soils. It is particularly associated with mires, water meadows, rush-pastures and stream-sides but can occasionally be found in wet woodlands and waste ground. The open flowers are attractive to a wide range of pollinating insects, particularly hoverflies.
Sneezewort germinates freely and can be sown at any time of the year, although in the wild it is normally from windblown seed that germinates in the autumn.