What is Vermiculite?

Have you ever read in a gardening book, or walked around a nursery, and heard the word vermiculite? Well, chances are fairly good that you have come across it at least the word at least once in your gardening life. But if you have ever wondered what is vermiculite, then you are in luck. The answer to this question, and a few simple methods for using it properly around the garden are listed below.

• What is it? Simply put, vermiculite is a heat resistant mineral that is composed of hydrated basalt that contains some rather unique properties. In the manufacturing world vermiculite has gotten something of a bad rap since it has been associated with asbestos insulation. However, the type that is usually found in gardening stores isn't all that harmful unless it is ingested, or burned and then inhaled. Keep in mind that the chances of this happening are miniscule since it is usually used as an ingredient for other things when gardening. Just don't grab a handful of the stuff and eat it. When used for gardening, it can provide some additional potassium and magnesium to plants, and acts as a natural sponge for other nutrients and moisture.
• Where to find it. This material can be found in just about any nursery or gardening store across the country. Typically it is found as an ingredient or filler for most kinds of potting mixes. You can also find fairly safe to handle types of the material in bulk as well.
• How to use it properly. There are many different uses for this mineral, but the most common is to add volume and air circulation to the soil that a plant is placed into. Vermiculite is commonly used in place of soil when starting seedlings indoors. This mineral can also be used to help start cuttings for both hardwood and softwood perennials and shrubs. Simply adding roughly one cup of vermiculite to six cups of a standard potting-soil can help create the perfect potting soil mix for any indoor plants that you may be considering. By adding between two and three inches of vermiculite to the top of your sandy soil garden, and then turning it in, can help dramatically increase the moisture retention levels of this notoriously difficult soil.