Long before the first poinsettia heralds the arrival of the season, there is an interesting botanical subterfuge going on in the basement beneath a cottage on horticulturist Henry Francis du Pont’s former Wilmington, Delaware, estate, which now functions as a much-visited garden, museum, and library. Countless stems of flowers are slipped over clotheslines or tucked into boxes of silica gel, their still-prismatic petals undergoing a drying process that will preserve them for an upcoming project.
