In Alexander's early work drawing was paramount, and after her time in documentary film it provided the impetus for an alternative documentary response to people and conditions in the South Wales coalfield during the wartime years before nationalisation, a project in which she was encouraged by film-maker Paul Rotha. Some of the striking portraits and landscapes from her extended visits to Rhondda in 1943, 1944 and 1945 appeared as illustrations to Miner's Day by B. L. Coombes and publications on post-war social and industrial reconstruction. After this, and exploiting her extensive botanical knowledge, she consolidated her work as an illustrator. She wrote and autolithographed The Story of Plant Life, one of the celebrated Puffin Picture Books, and embarked on a range of other illustration projects, developing her lithographic skill with the help of Barnett Freedman.
