From root to tip, the only part of the osmanthus which is of any value is her blossoms, which can be "used to flavor tea or wine, or to make pickles or hair conditioner" --by implication, finding uses for something inherently useless.
她渾身上下，算來只有花朵可做「收茗、浸酒、鹽漬，及作香茶、髮澤之類爾」，言下之意，不過是無用之用。