Blooming business - Lady detective novel, #1

Sonia Markhaleva, who is ready for any adventures, decided to organize a blossoming business, literally in the sense of the word. An acquaintance offers her to realize a large batch of... geraniums. The search for a buyer leads Sonya to a mysterious house, where she becomes an unwilling witness to a brutal murder. Having miraculously escaped from this hell, Sonya is happy - finally everything is behind her.
But it's not! As it turns out, it's only flowers... Visiting her acquaintances, to whom she gave geraniums, Sonya finds only cold corpses instead of living people....