: Rockwool has a naturally high pH (around 8.0) that can lock out nutrients. You must soak the cubes in slightly acidic water (pH 5.5 to 6.5) for at least an hour before use.
: Since it is manufactured at extremely high temperatures (3,000°F), it contains no pests, diseases, or weed seeds. buy rockwool cubes home depot
: Handle rockwool carefully. The tiny fibers can irritate your skin, eyes, and lungs; wearing gloves and a mask is recommended during handling. Where to Buy Locally vs. Online How To Start Seeds In RockWool Cubes Indoors : Rockwool has a naturally high pH (around 8