Start with high-confidence flower gardening books, then narrow by subgenre or adjacent topics.
Container and Fragrant Gardens
Peter Loewer
Hydrangeas
Naomi Slade
Lilacs
Ranunculus
A Year Full of Flowers
Sarah Raven
Foraged Flora
Louesa Roebuck, Sarah Lonsdale
Dahlias
Tara Austen Weaver
