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Struggling with inconsistent water distribution or algae growth in your hydroponic setup? The Cultiwool 4" x 4" x 4" Growing Blocks provide the professional-grade solution for uniform moisture management and healthy root development. These premium stonewool blocks are engineered to ensure every plant receives the exact hydration it needs, eliminating dry spots and waterlogging. Whether you are scaling up from Cultiwool round macro plugs or looking for a more compact alternative like the Cultiwool 3" x 3" x 3" growing blocks, these 100mm cubes offer the perfect balance of air and water retention.
Industry-first water chamber for precise dripper placement and uniform saturation.
Bottom cross-grooves improve airflow and prevent root pathogens by reducing ground contact.
UV-resistant black/white foil wrapping blocks light to stop algae growth in its tracks.
High-quality European mineral wool provides consistent texture for professional results.
| Specification | Value |
|---|---|
| Material | Premium European Stonewool |
| Dimensions | 4" x 4" x 4" (100mm x 100mm x 100mm) |
| Plug Hole Size | 38mm / 40mm |
| Quantity | 144 Blocks per Case |
| Special Features | Donut Ring, Drainage Grooves, UV Foil |
It is recommended to pre-soak the rockwool blocks in a nutrient solution adjusted to a pH of 5.5 to 5.8 to stabilize the medium before transplanting.
The Donut Ring acts as a water chamber that guides your dripper stake into the perfect position, ensuring water is distributed evenly throughout the entire 4-inch block rather than just one side.
Yes, each block comes individually wrapped in a black/white poly foil. This blocks light from reaching the damp surface, preventing algae growth and keeping the root zone clean.
These blocks feature a standard 38mm/40mm hole designed to perfectly accommodate Cultiwool round macro plugs or similar sized propagation cubes.
Absolutely. The cross-shaped grooves allow excess water to flow away more freely and increase airflow beneath the block, which helps prevent root rot and other water-borne pathogens.
Our specialists are happy to help. Call us or send a message and we'll get back to you within one business day (most of the time within a few hours.)
Equipping home growers, craft producers, and commercial operations across North America since 2016.