- Description
Research-Backed Stonewool Blocks for Precision Propagation & Early-Stage Cultivation
The Grodan® Gro-Block Improved GR4 Small is the result of a research partnership between Grodan, Wageningen University & Research, and top commercial growers across North America. This compact 3"x3"x2.6" block is engineered for propagation and early-stage crop development, delivering uniform water and nutrient distribution with Grodan’s most advanced steering capabilities.
Key Features
- 3" x 3" x 2.6" small format block with pre-cut plant hole — GR4 grade
- Strip packaging — commercial bulk format without retail wrapping
- Advanced Wetting Agent (AWA) for optimal fiber structure and uniform WC/EC distribution
- Improved hydrophilic technology for enhanced water distribution over the full block height
- Optimized wool structure for faster rooting-in and nutrient solution replenishment
- Maintains structure, firmness, and rigidity throughout the growing process
- Reusable and recyclable — part of Grodan’s sustainable growing program
What’s Included
Strip-packaged blocks, commercial bulk format. Intended for commercial use.
Grodan Gro-Block Improved Small GR4 – 3"x3"x2.6" w/ Hole | Strip
Grodan Gro-Block Improved Small GR4 – 3"x3"x2.6" w/ Hole | Strip
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At the leading edge of the market, Custom Hydro stands out by providing the growing industry with fertilizers that are not only of premium quality but also feature innovative
solutions tailored for the unique needs of hydroponic and organic farming practices.
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