She was born in Recklinghausen (North Rhine-Westphalia). She studied social work in Düsseldorf and worked from 1977 to 1979 in this profession in a jailhouse in Berlin. After that she studied law until 1985 and worked as lawyer.
Since 1979, she's been a member of the German Green Party (Bündnis 90/Die Grünen), first in the Alternative List in West Berlin. In the 1990s she was member of parliament and chairperson of the greens in the parliament of Berlin. From June 2000 to March 2001 she was chairperson of Bündnis 90/Die Grünen on the national level. She resigned with her becoming minister in the first Gerhard Schröder coalition in 2001. Since then she's the German Minister for Consumer protection, Agriculture, Food & Nutrition, know for her project of increasing the market shares of organic farms and organic food.