Perlite is a naturally-occurring volcanic glass that is used as a main component of most seed starting mixes. The small, white, lightweight pebbles are essential to improve aeration and drainage in seed starting mixes. It also has some incredible water-retention properties that will reduce the need to water as frequently. Each bag contains 8 quarts of perlite which is OMRI certified for organic production.
Perlite can be used to make your own seed starting mix or as a top dressing in seed starting trays. To make your own seed starting mix, we suggest using a blend of peat, vermiculite, and perlite. This will provide a fine blend that allows the seedling to establish a solid root ball for transplanting.
It can also be used to lightly cover seeds in seed starting trays. After making an impression in the seed starting mix and placing a seed in each impression, use perlite to lightly dust or cover the seeds. This technique has several benefits. It will prevent the growth of algae on the surface of the seed starting mix, it will reduce or eliminate the presence of fungus gnats which can harm seedlings, and it will also keep the seeds from being too wet during the germination process.
In addition to growing transplants like tomatoes and peppers, perlite can be used in the propagation of fruit trees and other perennials. We especially like to use it when propagating fig cuttings. After filling the propagation pot with potting soil, add a 1/2″ of perlite on top to provide the same benefits listed above.
- Making homemade seed starting mixes
- Top-dressing seed starting trays
- Aiding with moisture retention and aeration for plant cuttings