Poisoned Petals

Peggy Lee is just about to deliver some endangered sunflowers to Darmus Appleby when a gas explosion blows out his door-and Peggy finds her fellow botanist dead on the kitchen floor. And it's only two weeks later when Darmus's brother dies, after being found unconscious in a community garden with his brother's wedding ring in one hand and-in his pocket-a lovely purple Hyacinth with an overpowering scent.
  Now Peggy must follow her nose-and some cryptic clues from an internet informant-to root out a killer before he strikes again.  Gardening tips included!