Large Bitter Cress is a medium-sized to fairly tall perennial. It resembles Cuckoo Flower in many ways. The flowers of Large Bitter Cress are smaller, however, and grow in a broader cluster; they are nearly always white whereas those of Cuckoo Flower are lilac coloured.
The anthers are different also; instead of being yellow like Cuckoo Flower they are a vivid violet colour. The leaflets are oval and like watercress. The plant grows in wet places, riversides and damp woods, mainly on peat. It is rare in Ireland and only found in the northern counties, chiefly around Lough Neagh.
The flowers bloom from April to June.
Large Bitter Cress grows throughout Europe to Asia Minor, often in damp alder woods.