Grow stones are touted as the more environmentally friendly medium for those concerned with the strip-mining aspects of clay pebbles. Grow stones are made from recycled glass materials like beer, wine, and soda bottles. Sounds like they raided someone’s liquor cabinet for a good cause.
Sure to Grow is a plastic-based growing medium that runs the gamut among users from love to hate. Or it might just be marketing versus the gardening community, one of the two. This is one to try so you can form your own opinion.
Perlite is puffed volcanic glass that has superior oxygen retention due to its porous state but easily shifts or washes away when water comes in direct contact with it. It’s best for this one to be mixed with other growing media to keep it in place.