Netherlands for almost 60 years, was one of the most influential landscape architects of the 20th Century. A leading proponent of modernist design, she introduced clean lines, geometric shapes and innovative materials. One of the few women members of CIAM, she collaborated regularly with architects including Aldo van Eyck and Gerrit Rietveld, often on much needed social housing schemes. Uniquely, she combined this modernist approach with an extensive knowledge of plants and planting, which she learnt in her father's Royal Moerheim Nursery in Dedemsvaart. At the nursery, she met Gertrude Jekyll - who greatly influenced Mien as she developed her own loose, natural style of planting - and created 30 experimental gardens from which lessons which can still be learnt.