He treated much of the Solanaceae for Flora Europaea, started the Solanaceae Newsletter and organised the first Symposium on the Solanaceae.[3]
At Birmingham he started the M.Sc. course in the Conservation and Utilization of Plant Genetic Resources, which trained international students.[3]
Working with Birmingham Natural History Society and Dorothy Cadbury he produced "A computer - mapped flora and study of the county of Warwickshire" (1971). This was an innovative use of computers at the time using Punched tape storage, which led to problems later on when the computer department updated their system and the old tapes had to be read slowly so as not to damage them.[7]
A computer-mapped flora, a study of the County of Warwickshire. Cadbury, D. A., Hawkes, J. G., Readett, R. C. (1971). Birmingham Natural History and Philosophical Society (Birmingham, England), Academic Press. ISBN9780123333605
A bibliography of plant genetic resources. Hawkes, J. G., Williams, John Trevor, Hanson, Jean (1976). Rome: International Board for Plant Genetic Resources.
The Biology and taxonomy of the Solanaceae. Hawkes, J. G., Lester, R. N., Skelding, A. D. (1979). Linnean Society of London, Academic Press. ISBN9780123331502
The potato: evolution, biodiversity and genetic resources. Hawkes, J. G. (1990). London: Belhaven. ISBN9781852930455
Richard N. Lester (2005). "Book Review - Hunting the Wild Potato in the South American Andes: Memories of the British Empire Potato Collecting Expedition to South America 1938–1939". Genetic Resources and Crop Evolution. 52: 483–488. doi:10.1007/s10722-005-8253-3.
'HAWKES, Prof. John Gregory', Who Was Who, A & C Black, 1920–2008; online edn, Oxford University Press, Dec 2008 accessed 30 May 2011
