Vermiculite is a naturally occurring mineral that is often used in gardening. It is a lightweight and sterile medium that can help to improve soil quality and moisture retention. Vermiculite is made up of layers of minerals that expand when heated, creating a spongy, lightweight material that is ideal for gardening. When added to soil, vermiculite can improve aeration and drainage, making it easier for plants to grow healthy roots. It also helps to retain moisture in the soil, which can be especially beneficial in dry climates or for plants that require consistent moisture. Vermiculite is often used in seed starting mixes, as it provides a sterile environment that helps prevent soil-borne diseases. Overall, vermiculite is a valuable tool for gardeners looking to improve soil quality and plant health.