Grodan Rockwool Slab: The Ultimate Propagation Substrate

Experience the exceptional performance of Grodan Rockwool Slabs, the ultimate propagation substrate crafted from hydrophilic fibres, offering an eco-friendly and high-quality solution for your gardening needs. These rockwool slabs are designed to work with seeds, cuttings, and vertical wall gardens, providing the ideal growing medium for a thriving garden.

Features and Benefits

  • High-quality hydrophilic fibres: The revolutionary fibres promote excellent water retention and aeration, ensuring superior nutrient distribution and plant growth.
  • Environmentally friendly: Manufactured sustainably, Grodan Rockwool Slabs help reduce your ecological footprint and support a greener planet.
  • Wide applicability: Perfect for raising seeds, growing cuttings, replanting from rockwool cubes, and designing vertical wall gardens.
  • Consistent size and thickness: Each slab measures 90cm in length, 30cm in width, and 7.5cm in thickness, ensuring uniform growth across your garden.
  • Available in single packs and 8 packs: Purchase according to your needs, whether you require just one or a bulk pack for larger gardening projects.

How to Use

  1. Before use, thoroughly soak the rockwool slabs in water with a pH level of 5.5 to 6.0 for 30 minutes, ensuring complete saturation.
  2. Once soaked, allow the slabs to drain excess water for a few minutes.
  3. Place seeds or cuttings evenly on the slab's surface, ensuring ample spacing for optimal growth.
  4. Monitor the moisture levels regularly, and keep them adequately watered according to your plants' needs. Make sure pH levels are maintained between 5.5 and 6.0.

Aqua Gardening Suggests These are Best For

Grodan Rockwool Slabs are best suited for hydroponic gardeners, vertical wall garden enthusiasts, and those looking for a versatile, eco-friendly propagation substrate for seeds, cuttings, and replanting projects. Ideal for both commercial growers and home gardeners aiming for thriving, healthy plants.

Click here to read our handy guide on hydroponics-or-aquaponics/">raising seeds with rockwool.


What are the key features of Grodan Rockwool Slabs?

Grodan Rockwool Slabs are made from hydrophilic fibres that provide excellent water retention and aeration for plant roots. They are suitable for raising seeds, growing cuttings, and transplanting plants from Rockwool cubes. Additionally, this substrate is ideal for vertical wall gardens and is made sustainably to ensure minimal environmental impact.

How do I use Grodan Rockwool Slabs for propagation?

Simply place your seeds or cuttings into the Rockwool Slab and provide them with the necessary water, nutrients, and light they need to thrive. As the plants grow, their roots will penetrate the Rockwool, making it easy to transplant them to larger growing spaces or other growing mediums if necessary.

Can I use Grodan Rockwool Slabs for both indoor and outdoor gardening?

Yes, Grodan Rockwool Slabs are suitable for both indoor and outdoor use. They are a versatile growing medium that can be utilised in various hydroponic systems or traditional soil-based gardens.

How long can I expect my plants to stay in Grodan Rockwool Slabs?

The length of time plants can stay in Grodan Rockwool Slabs depends on the plant species and the growth stage. However, they are designed to support your plants throughout their entire propagation phase. Once your plants reach the desired growth stage, you can transplant them to larger environments or other growing mediums.

How do I transplant my plants from Grodan Rockwool Slabs to another growing medium?

To transplant, gently remove the plant along with the surrounding Rockwool from the slab. Place the plant and attached Rockwool directly into the new growing medium, such as soil or a larger hydroponic system. This minimises root damage and provides a seamless transition for the plant.

How do I store unused Grodan Rockwool Slabs?

Unused Grodan Rockwool Slabs should be stored in a cool, dry place away from direct sunlight. Ensure they are wrapped or covered to protect them from dust, debris, and potential contaminants. Proper storage ensures the slabs maintain their optimal growing properties when you are ready to use them.

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