Botany had become by the end of the 18thC a science appropriate for women. By 1800, books like William Mavor's The Lady and Gentleman's Botanical Pocket Book argued that 'botanizing'--rummaging about in the countryside looking at plants-- was actually good for one's health! Here's a great quote:
Whether we consider the effect of Botany as enlarging the sphere of knowledge, or as conducive to health and innocent amusement, it ought to rank very high in the scale of elegant acquirements. (Mavor vi)
But when Sophia teaches the hero Aidan Somerville, Duke of Forster something of what she knows about plants, he turns it into a seductive moment:
Then he had kissed her, naming all the flowers by their botanical names in a line from her lips, down her neck, and to her breasts, and back to her mouth, until her kisses, sweet against his lips, turned mad with longing. In his youth and inexperience, he'd mistaken her fervor for love.
For more on flowers, botany, and the language of flowers in 1819, check out the links for science and medicine under the Regency Life menu.