By Strong, Roy/ Published 1991, HarperCollins, Great Britain / Gardening

By Allwood, Montagu C./ Published 1935, Allwood Bros. Sussex, England / Gardening

By Cross, John E/ Published 1951, Saturn Press, London / Gardening

By Kawase, Toshiro/ Published 1999, Kodansha International, Tokyo, Japan / Gardening

By Garnett, T. R. [Editor]/ Published 1986, Nelson, Melbourne, Australia / Gardening

By Le Lievre, Audrey/ Published 1980, Faber & Faber, London / Gardening

By Howe, Bea/ Published 1961, Country Life Ltd, London / Gardening

By Irvine, Susan/ Published 1992, Hyland House, South Yarra, Australia / Gardening

By Spry, Constance/ Published 1953, J M Dent & Sons, London / Gardening

By Guest, C. Z. / Published 1987, McGraw-Hill, USA / Gardening