Stems are made of rattan reed which help deliver the scented oil to the flowers. Flowers are made from sola wood so they easily absorb the oil and diffuse the scent into the air. All you need is to drop the flowers in a vase filled with reed diffuser oil. It all depends on the oil but generally it will take up to a week to travel up to the flowers and diffuse. Please do not use water with this flowers since water can create mold. Flowers are about 9-10 inches height. Made to order in Beautiful Monterey, California