The Ashleigh & Burwood Scented Home Reed Diffuser Refill Bottle for refilling you Scent Home Glass Bottle diffuser. Choose from fragrances ranging from sweet and floral to spicy and woody. We recommend changing the reeds with each new bottle of fragrance. This is because the reeds can become clogged with fragrance and dust, stopping them from working efficiently. HOW LONG WILL THEY LAST: Reed Diffuser refiill will last up to 3 months. This can vary based on a variety of factors, such as airflow, ambient humidity, ambient temperature and the number of reeds used.