- Molten Rock Soilless Culture Substrate: A soilless culture substrate made from melted rock, spun into sugar-like fibres and compressed into cubes to ensure long-lasting performance. The growth cube plugs (25 x 25 x 40 mm) are ideal for propagation in hydroponic systems. They support seedling development while maintaining optimal humidity for germination. The special structure creates ideal conditions for root growth and plant settlement. - Good air permeability: These growth cubes have low stacking density, a light texture, high porosity and good breathability, so plants can breathe and grow healthily. The light texture and porosity allow easy penetration of the roots while maintaining sufficient moisture without waterlogging. The balanced water-to-air ratio of these growth blocks helps seedlings thrive in a hydroponic garden. - Strong water absorption and drainage: The bottomless cultivation substrate has strong water absorption and good drainage properties, providing a suitable environment for plant growth. Nutrient solution can reach roots through rock wool, which supports plant growth. The water absorption rate is over 800%, and the water and fertiliser performance is good. Excellent water absorption capacity and efficient drainage help maintain the ideal moisture balance for your plants. - Non-toxic and sterile: After high temperature treatment, these growth starter cube plugs are non-toxic and sterile, providing a safe and healthy medium for plant growth. Their clean nature makes them ideal for indoor gardening, hydroponic systems and professional growing operations where cleanliness matters. - Use scenarios: Ideal for seedling propagation in hydroponic systems; suitable for indoor gardening and home hydroponics; appropriate for professional greenhouse or commercial operations that require a clean, sterile substrate.