English naturalist, botanist, and theologian known as the “father of English botany.” His A New Herball was the first English herbal to include original material.

Turner studied at Pembroke Hall, Cambridge. His dissatisfaction with derivative herbals led him to write Libellus de re herbaria novus (1538), the first essay on scientific botany in English. Turner's fervent Protestant religious beliefs led to several periods of exile to the European continent, during which he studied with and met numerous naturalists and learned about contemporary discoveries in botany. An extended version of the Libellus entitled The Names of Herbes (1548) was written in English, containing German and French synonyms, and included unorthodox and vivid original observations. He served as the dean of Wells Cathedral from 1550 until the accession of Queen Mary in 1553 sent him into exile. After her death he returned to Wells until his suspension for nonconformity in 1564.

Turner's best-known work, A New Herball (in three parts; 1551–68), demonstrated his medical bias. He chose to write in English, the vernacular language, so that practical botanical and medical knowledge would be widely available to medical practitioners and apothecaries. Turner's works were used extensively by later botanists such as John Ray and Jean Bauhin.