Grodan Improved Gro-Block GRI4 40/40 – Growing Block 7.5 x 7.5 x 6.5 cm

The Grodan Improved Gro-Block GRI4 is a professional stone wool growing block measuring 75 x 75 x 65 mm, featuring a large 40/40 mm planting hole. The block is designed for uniform root development and precise root-zone management in professional hydroponic cultivation.

The Grodan Improved product line combines an optimised fibre structure with Advanced Wetting Agent technology. This enables uniform distribution of water and nutrients throughout the entire substrate volume, supporting stable water content (WC) and consistent electrical conductivity (EC) in the root zone.

The improved water distribution promotes fast and uniform rooting, allowing plants to efficiently utilise the available substrate volume. Precise control of WC and EC makes this growing block particularly suitable for vegetative and generative crop steering strategies.

The large planting hole accommodates compatible propagation blocks, including 40 mm Grodan Mini-Blocks. For further plant development, the blocks can be combined with suitable Grodan growing slabs.

Benefits

• Optimised fibre structure with Advanced Wetting Agent
• Uniform distribution of water and nutrients
• Consistent water content (WC) and stable EC behaviour
• Supports fast and uniform root development
• Precise irrigation and nutrient management
• Suitable for vegetative and generative crop steering
• Large planting hole for compatible 40 mm propagation blocks
• Developed for professional hydroponic cultivation

Product Specifications

• Brand: Grodan
• Product line: Improved Gro-Block
• Type: GRI4 40/40
• Material: Stone wool
• Dimensions: 75 x 75 x 65 mm
• Planting hole: 40/40 mm
• Manufacturer article number: 354423
• Sales unit: 1 growing block
• Application: Professional plant propagation and hydroponics