 When World War II ended in 1945, as a former member of the Women's Land Army, Gillham was eligible for a grant to go to university; something her family couldn't have afforded in peace-time.She became a post-war student at the University of Wales at Aberystwyth, gaining an undergraduate degree in Agriculture followed by a first-class honours in Botany in 1949.She was also involved in extracurricular activities at university, becoming captain of the gymnastics, folk dance, rowing and swim team.