In the mid-1980s/1990s John Sherwood wrote ten or so mysteries featuring Celia Grant, a garden nursery owner in England. I've read a few of them; it doesn't seem to matter if you read them in order - I haven't, anyway. In this adventure, Celia heads for New Zealand to await the birth of a grandchild. One of her friends entreats her to find out what's become of a not very well liked relative a blowhard gentleman who has some mysterious agenda involving New Zealand endangered wildflowers. Celia reluctantly agrees to look for him and is soon embroiled in a pitched battle between the "tree-huggers" and rapacious developers. When a woman is murdered, and it looks like Celia had motive and opportunity, she has to really dig in and find the root of the matter. Her knowledge of botany and nursery practices enables her to figure out the motive and the real killer.
This is a pleasant mystery, definitely in the cozy class, but not world shaking either in plot, characters, or memorable prose. Celia is smart and interesting, but I can't remember much about any of the supporting cast. As a gardener, I enjoy the various snippets of plant information and they're not so overwhelming as to take over the story. Anyone who likes cozy mysteries can be assured of a pleasant few hours.