Grodan Stonewool (rockwool) is made from molten rock spun into cotton candy-like fibers and then compressed into cubes, blocks, or slabs. Where other rockwool brand manufacturers cut all sizes from one batch of wool, Grodan is unique by making different types of fibers. The purpose is to support the requirement of the plant in the different plant stages. Grodan has a tremendous capacity for absorbing nutrient solution while retaining plenty of oxygen for rapid plant growth. Grodan comes in graduated sizes. Seedlings started in cubes are easily transferred to blocks and then onto slabs, if desired. Seedlings or cuttings started in the Grodan cubes can also be transplanted into more traditional planters and growing mediums. Grodan Blocks -Grodan Delta blocks are the most uniform blocks available on the market. They feature improved grooves at the base to promote better drainage. They are available in a large assortment of sizes and configurations to suit all types of plants. These growing blocks are used for direct sowing or "blocking on" of Macro and Multiblock raised plants. AO 36/40 plugs fit well into the hole sizes provided by the blocks. The blocks can then be placed on top of a slab to provide for a larger growing volume. Hugo is the largest of the growing blocks. It provides enough growing volume to support a larger plant, so it does not need to be placed on top of a slab.

New Formulation with "IMPROVED" Models:

Leverage the benefits of products developed alongside plant scientists, that are specifically engineered to deliver real results for your crops. Grodan Gro-Blocks Improved with Advanced Wetting Technology — our improved stone wool substrate.

Real Science
Grodan partnered with the Wageningen University and Research facility in The Netherlands and top growers throughout North America to identify the optimal stone wool substrate and irrigation strategies for specialty crops. The result of months of scientific research and trials is Grodan Gro-Blocks Improved.

Real Results
The result of this scientific rigor is Grodan Gro-Blocks Improved with our Advanced Wetting Agent. In the scientific trials, plants grown in these new blocks had faster rooting-in, higher yields, improved quality, and less water and nutrient usage throughout the entire crop cycle.

Real Improvement
These leading-edge blocks have the optimal fiber structure and physical properties
for crop uniformity, more even Water Content (WC) and Electrical Conductivity (EC) distribution throughout the entire block, and the greatest steering capabilities available. Water distribution is more uniform throughout the entire block which is the basis for a well-defined root system with higher capacities for water and nutrient uptake to produce robust and vigorous crops.