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Grodan Rockwool / Stonewool Gro-Slab – 12″ x 36″ x 3″




Made in Denmark since 1969, Grodan Rockwool (also called stonewool) is widely recognized as the ideal soilless substrate. For any growing application, Rockwool offers speed, ease of use, and cleanliness. Rockwool is an alternative to coco coir and expanded clay for hydroponic applications.

  • The 3″ x 36″ x 12″ Slab is best fit for use in hydroponic drip systems.
  • Individually wrapped cubes hold the Rockwool’s shape and prevent algae growth.
  • Grodan Rockwool Slabs are excellent for commercial or hobbyist cultivation of leafy greens, smaller vegetable crops, and other high-value plants.

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Grodan Rockwool / Stonewool Gro-Slab

Grodan Improved Gro-Slabs and Uni-Slabs offer a wide control range to steer your crop using irrigation strategies. Featuring the Advanced Wetting Agent, Gro-Slabs offer more uniform WC and EC distribution throughout each slab and from slab to slab. Fast rooting and vigorous growth throughout the entire growing cycle improve cannabis plant health, better resilience, and higher yields. The improved slab structure and physical properties guarantee rapid resaturation within a wide steering range.


  • Single-plant and multi-plant slab options
  • Vertical fiber orientation
  • Inert hydrophilic fibre technology
  • High resaturation capacity
  • Uniform water distribution throughout the Grodan Improved Uni-Slabs
  • Choice of no-hole or precut-hole versions


Grodan Gro-Slab Wetting Instructions

Grodan Gro-Slab Datasheet and Benefits

Weight 3.6 lbs
Dimensions 36 × 12 × 3.25 in


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