Grodan Improved GR40 Uniblock, 8" x 8" x 4", case of 36

Research-Backed Stone Wool Block for Crop Uniformity, GR40 Uniblock, 8in x 8in x 4in

Grodan Improved stone wool blocks were developed with Wageningen University and Research in the Netherlands to identify optimal substrate and irrigation strategies for specialty crops.

These blocks use an Advanced Wetting Agent and an optimized fiber structure for crop uniformity, more even Water Content and Electrical Conductivity distribution, and steering capabilities that support a well-defined root system with higher water and nutrient uptake.

This GR40 Uniblock, 8in x 8in x 4in block is packaged as bulk in a case of 36, without retail wrapping or labeling.

Key Features & Benefits

• Advanced Wetting Agent — improves water distribution throughout the block
• Optimized Fiber Structure — supports crop uniformity and even WC/EC distribution
• Well-Defined Root System — higher capacity for water and nutrient uptake
• Commercial Bulk Packaging — shipped without retail boxes or labelling for large-scale use

Who Should Use Grodan Improved Blocks

Suited to commercial growers who want research-backed water distribution and steering capability at scale.

About Grodan

Grodan manufactures stone wool growing media, including cubes, blocks, and slabs engineered for consistent water and root development.

Frequently Asked Questions

Who developed this block?

Grodan, in partnership with Wageningen University and Research.

What makes it different from standard stone wool?

An Advanced Wetting Agent and optimized fiber structure for more even water distribution.

How is it packaged?

packaged as bulk in a case of 36, without retail wrapping or labeling.

What size is this block?

GR40 Uniblock, 8in x 8in x 4in.