I do see why miss Yuuki hired you, I believe. [So earnest and enthusiastic. Sebastian appreciates a positive attitude towards work (as long as it's paired with some level of competence or at least potential).]
Have you an interest in any specific type of plants? If it is any of the ones sold at the shop, it should be easy to work in some lessons on them as you handle them.
[He's not outright offering to teach her stuff while they work. Although he kind of is.]