Grodan Rockwool Grow Slab 8" x 3" x 36"

Description

8 x 3 x 36 inch rockwool slab, most popular size. Growing Slabs are a great choice for vegetable crops or almost any plant that needs extra support at the base. Slabs come wrapped in U.V. resistant plastic that makes a good container for the roots to thrive.
A 3 foot slab could hold up to 5 plants. To use, cut a hole in the plastic the size of the rockwool cubes you use. Full the slab with water to moisten all the rockwool. Flip over the slab and cut drainage slits in the bottom across the width. Flip the slab back over and place your plants growing in cubes on the holes. The roots will grow into the slab. Water with a drip system.
Most plants can grow in Gro-Slabs but they are particularly good for growing large vine crops such as tomatoes or cucumbers.  For plants growing outdoors during mid-day sun Gro-Slabs provide a good water buffer.
The 12” Gro-Slab is considered a wet slab due to its horizontal fibers.  It holds more water than other slabs and can support more plants than any stone wool slab.  The rest of the Gro-Slabs are all comprised of vertical fibers, which allow for faster drainage and a drier slab.