Sources for Perlite

What Is Perlite?

• Essentially, perlite is glass. This white volcanic glass expands in heat and turns into lightweight white kernels, similar to Styrofoam in both appearance and weight. When lava flows from a volcano and cools extremely quickly, the lava retains water and turns into glass. Vast deposits of this mineral are then available for mining. The United States has the largest perlite mining industry, in the western mountains from New Mexico to Idaho. There are so many vast deposits of this mineral yet to be tapped that mining from active volcanoes is not necessary. Since it is an environmentally friendly mineral and requires no chemical processing, perlite is safe and easy to acquire.

Uses

• The high oxygen content and water retention and release abilities of perlite make it an ideal product for many applications.

  As a construction filler, perlite is ideal for its rot, vermin and pest-repellent nature, as well as its use as high-quality insulation against both heat and sound. It is also highly heat-resistant and therefore a safe alternative filler for construction projects. It is far safer than asbestos or fiberglass insulation for both construction workers and the people using the finished structures.

  In gardening, perlite is the perfect root-growing, soil-free environment, as it is completely sterile and free of weeds. This lightweight product also has a neutral pH, which is ideal for fledgling plants that are fickle, and it retains enough water to sustain a plant for several days without watering. While it retains water, it also allows water to flow through rather than stagnate, which reduces the chance of root rot.

Where To Find or Buy

• Perlite can be purchased at almost any home and garden store. Check large chain stores first, followed by large local garden centers. Despite suggestions from salespeople, do not substitute perlite for vermiculite, as these are very different products. It is sold in bags similar in size to potting soil, and one bag goes a long way.

Home Garden How-to

• This is an example of how to take clippings from a spider plant and get them to grow roots in perlite for planting:

  Cut spider plant babies at the connection with the stalk so that you have just the clustered head. Put perlite in a plastic seeding container with holes in the bottom, and put this container in a larger container with no holes in the bottom, such as a tray. Using a pencil, dig a hole in the middle of the perlite, and stick the spider plant cluster in the hole; then push the perlite into the plant so that it is secure.

  Fill the tray with water. Let this sit for a few weeks, and the clusters will grow roots, at which point they can be transplanted into soil.