Precision-engineered stone wool grow blocks for strong, uniform root development from clone to harvestCultiwool Original Growing Blocks provide a stable, steerable root environment for professional horticulture. A homogeneous fiber structure delivers uniform water distribution and a balanced air-to-water ratio, giving you predictable crop performance through every stage of cultivation. Manufactured in Europe from high-quality, RHP-certified stone wool with excellent dimensional stability.The cross-groove base ensures efficient drainage and optimal oxygen availability in the root zone, while the integrated donut ring — a water chamber around the plug hole — promotes even irrigation and consistent EC and moisture distribution throughout the block.Available Sizes:4" x 4" x 2.5" · 4" x 4" x 4" · 6" x 6" x 4" (with or without Donut Ring) · 6" x 6" x 6" (with or without Donut Ring) · 8" x 8" x 8" Cross-groove base for efficient drainage and root-zone oxygen Integrated donut ring for uniform EC and moisture Homogeneous fiber structure for even water uptake High dimensional stability through intensive crop cycles Excellent re-wetting capacity after dry-back Clean, inert, pest-free substrate RHP-certified European stone wool Sold by the case
