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Germinating seeds in rock wool is a simple technique widely used in hydroponics. It allows you to better control moisture, avoid soil diseases and accelerate germination.
Take advantage of protected seedbeds for sensitive plants.
- Crop rotation
- Compost contribution
- Pest control
If you've never tried it, here's a basic guide to get started.
What is rock wool
It's an inert substrate made from volcanic rock. It doesn't provide nutrients, but retains water very well and keeps the root area aerated.
Advantages for germination
- Better humidity control.
- Less risk of soil fungi.
- Clean roots that are easy to transplant.
- Ideal for hydroponic systems.
That's why it's so popular in precision seedbeds.
How to germinate seeds in rock wool
1. Hydrate the rock wool cubes with water. 2. Drain the excess to avoid waterlogging. 3. Place one or two seeds per cube. 4. Keep in a warm place with indirect light. 5. When the first leaves appear, you can transplant.
Useful tips
- Don't oversoak the cube.
- Use a tray with a lid to maintain humidity the first few days.
- Label your crops so you don't confuse varieties.
Conclusion
Rock wool is an excellent option for germinating seeds without soil. If you want to start hydroponics or simply have a clean and controlled seedbed, it's a technique worth trying.
If you want to get started, the Model I polytunnel is our most popular choice for home gardens — easy to assemble and with 48h delivery.