Avens produces large quantities of flowers in late spring and early summer. The colour range is usually limited to shades of yellow, orange or red.
About 50 species are to be found around the world, in the cooler regions of Europe, Asia, North and South America, Africa and New Zealand. Most species are found on moist, fertile soil in meadows or woodland, but some originate in open areas with poorer soil.
Most varieties prefer a humus-rich soil, although some are happier with better drainage. Sun is ideal for many, and increases flowering, although most will tolerate some shade.