The RHS is an excellent resource for any gardener: www.rhs.org.uk. Members can also send or take in samples for plant or pest and disease identification, and soil composition tests.
Useful books for reference and inspiration:
▪ RHS Vegetable and Fruit Gardening edited by Michael Pollock (Dorling Kindersley, 2012)
▪ RHS Grow for Flavour by James Wong (Mitchell Beazley, 2015)
▪ RHS Pests and Diseases by Pippa Greenwood and Andrew Halstead (Dorling Kindersley, 2009)
▪ Creating a Forest Garden by Martin Crawford (Green Books, 2010) is the definitive work on incorporating edible plants into all levels of a garden
▪ The New Kitchen Garden by Mark Diacono (Saltyard Books, 2015)
▪ The Flavour Thesaurus by Niki Segnit (Bloomsbury, 2012)
It is also worth seeking out kitchen gardens. Many have tasting days at which you can try different varieties of fruits and vegetables before you buy, and experts on hand to offer growing advice as well.
You can contact me on twitter, @Holly_E_Farrell