Introduction to Grodan Rockwool Cubes
Grodan Rockwool 1.5" cubes are an inorganic and sterile growing medium derived from spun molten rock. These cubes are designed to provide an optimal environment for starting seeds and rooting plant cuttings, offering excellent aeration and moisture retention for healthy root development.

Image: Grodan Rockwool 1.5 inch cubes, showing the packaged strips and individual cubes ready for use.
Característiques clau
- Sterile Growing Medium: Made from inorganic spun molten rock, ensuring a clean and disease-free start for plants.
- Optimal Aeration: Provides approximately 20% air space when saturated, crucial for root respiration and preventing waterlogging.
- Excellent Moisture Retention: Designed to hold water efficiently, reducing the frequency of watering.
- Ideal for Propagation: A superior medium for successfully rooting cuttings and germinating seeds.
- Nutrient-Free: Does not contain nutrients, allowing for precise control over nutrient delivery from the start.
- Mida convenient: Each cube measures 1.5 inches square, suitable for various propagation trays and hydroponic systems.
Muntatge i preparació
Before using Grodan Rockwool cubes, it is essential to condition them to achieve the optimal pH level for plant growth. Rockwool typically has a high pH (around 7.0-8.0) directly out of the package, which can be detrimental to young plants if not adjusted.
Conditioning Steps:
- Prepare pH-Adjusted Water: Fill a clean container with water. Adjust the pH of the water to a range of 5.5-6.0 using a pH down solution (e.g., phosphoric acid or citric acid). A pH meter is recommended for accuracy.
- Soak the Cubes: Submerge the Grodan Rockwool cubes completely in the pH-adjusted water. Allow them to soak for a minimum of 8 hours, or preferably 24 hours. This process helps to stabilize the pH within the cubes and fully saturate them.
- Do Not Squeeze: After soaking, gently remove the cubes from the water. Do not squeeze or wring out the cubes, as this can damage their internal structure and reduce their air-holding capacity. Allow excess water to drain naturally.
- A punt per al seu ús: The conditioned cubes are now ready for planting seeds or inserting cuttings.
Instruccions de funcionament
For Seed Germination:
- Place Seed: Gently place one or two seeds into the pre-drilled hole at the top of each conditioned rockwool cube.
- Cover (Optional): For very small seeds, a light covering of vermiculite or a small piece of rockwool from another cube can be used to maintain humidity, but often the hole itself is sufficient.
- Provide Environment: Place the planted cubes in a propagation tray or dome to maintain high humidity, which is crucial for germination. Ensure adequate light and temperature for your specific seed type.
- Monitor Moisture: Keep the rockwool cubes consistently moist but not waterlogged. The cubes should feel damp al tacte.
- Trasplantament: Once seedlings have developed a strong root system visible at the bottom of the cube, they are ready for transplanting into a larger growing medium or hydroponic system. The entire cube can be placed directly into the new medium.
For Rooting Cuttings:
- Prepare Cutting: Select a healthy, non-flowering stem cutting from your desired plant. Remove lower leaves and dip the cut end into a rooting hormone if desired.
- Insert Cutting: Carefully insert the prepared cutting into the pre-drilled hole of a conditioned rockwool cube. Ensure the cutting is secure and makes good contact with the rockwool.
- Provide Environment: Place the cubes with cuttings in a propagation dome or misting chamber to maintain high humidity and prevent wilting.
- Monitor Moisture: Keep the rockwool cubes consistently moist. Avoid overwatering, which can lead to rot.
- Root Development: Roots typically begin to emerge from the sides and bottom of the cube within 1-3 weeks, depending on the plant species.
- Trasplantament: Once a robust root system has developed, the rooted cutting, still in its rockwool cube, can be transplanted into a larger growing system.
Manteniment i cura
Grodan Rockwool cubes are designed for ease of use, but proper maintenance ensures optimal plant health.
- Reg: Monitor moisture levels daily. Water when the top of the cube feels slightly dry. Ensure proper drainage to prevent waterlogging.
- Nutrient Application: Since rockwool is inert, nutrients must be supplied through the water. Begin with a diluted nutrient solution suitable for seedlings or cuttings once the first true leaves appear or roots are established. Gradually increase nutrient strength as the plant grows.
- pH Monitoring: Regularly check the pH of your nutrient solution (if applicable) and the runoff from the cubes to ensure it remains within the ideal range (typically 5.5-6.5 for most plants in hydroponics).
- Neteja: Maintain a clean growing environment to prevent pest and disease issues.
Resolució de problemes comuns
| Problema | Causa possible | Solució |
|---|---|---|
| Poor Germination/Rooting | Incorrect pH during conditioning; insufficient humidity; improper temperature; old seeds/unhealthy cuttings. | Re-condition cubes with correct pH; increase humidity (use a dome); adjust temperature; use fresh seeds/healthy cuttings. |
| Yellowing Leaves (Seedlings) | Nutrient deficiency (too early for nutrients or solution too weak); incorrect pH preventing nutrient uptake. | Introduce a very diluted nutrient solution; check and adjust pH of water/solution. |
| Wilting Plants | Underwatering; overwatering (root rot); too much light/heat. | Check moisture, water if dry; ensure good drainage, allow to dry slightly if overwatered; reduce light intensity or temperature. |
| Algae Growth on Cubes | Excessive light exposure to the rockwool surface; overwatering. | Cover exposed rockwool surfaces (e.g., with perlite or black plastic); ensure proper watering cycles. Algae is generally harmless to plants but indicates conditions that could lead to other issues. |
Especificacions del producte
- Tipus de producte: Rockwool Growing Cubes
- Dimensions del cub: 1.5 inches x 1.5 inches x 1.5 inches (approximate)
- Quantitat de paquet: 45 cubes (3 strips of 15 cubes)
- Material: Spun Basalt Rock (Inorganic)
- Esterilitat: estèril
- Nutrient Content: None (Inert)
- Número de model: GL56713040STRIP
- Fabricant: Grodan
- País d'origen: Països Baixos
Garantia i Suport
Grodan Rockwool cubes are manufactured to high-quality standards. For specific warranty information or product support, please refer to the official Grodan weblloc web o contacteu directament amb el servei d'atenció al client. Conserveu el rebut de compra per a qualsevol reclamació de garantia.





