Rockwool Seed Starter | Propagation Cubes | Hydroponic Growing Medium

Yes. Once roots grow, the cube can sit in clay pellets or perlite in a net pot or a hydroponic system.

They hold water and air together, and a seedling can move into a hydroponic system in its cube.

Seedlings can stay in a rockwool seed starter until roots are well-established and leaves are forming. Typically, this is 2-3 weeks before transplanting to a larger pot or hydroponic system.

Yes. Flowers such as marigolds, petunias and zinnias can be started in them.

We do not claim they prevent root rot. They drain well, which helps, but too much water can still cause problems.

No, but a humidity dome helps keep the cubes moist and warm, which is useful in a dry room.

They come as pre-formed cubes that hold water and air together, so a seed sits in an even, moist medium.

While rockwool starter cubes retain moisture well, overwatering can lead to sogginess, reducing aeration. Monitor moisture levels and ensure cubes are moist but not soaked for the best results.

The fibres hold water, so the seed stays moist without sitting in water.

Yes. Basil, mint and oregano can be started in them, then moved to a hydroponic system or a pot.

The cubes contain no nutrient, so add a diluted hydroponic nutrient to the water once seedlings appear.

We do not make environmental claims for this product.

Yes, you can adjust pH levels in rockwool starter plugs by soaking them in pH-balanced water (around 5.5-6.5) before planting. This prevents pH imbalances that can impact seedling growth.

Rockwool starter cubes are popular in hydroponics due to their ability to retain moisture and aeration simultaneously. They provide a stable medium for roots, ideal for nutrient-rich hydroponic systems.

To transplant from a rockwool seed starter , wait until roots are visible. Gently transfer the cube to a larger container or hydroponic system, ensuring the roots remain undisturbed for a smooth transition.

While rockwool starter plugs are designed for controlled environments like hydroponics or greenhouses, they can be used outdoors. However, ensure they’re kept moist and shielded from extreme weather.

They hold the nutrient solution close to the roots.

A rockwool seed starter requires light, consistent watering to stay moist but not soaked. The cubes hold water well, so monitor moisture levels and avoid overwatering to maintain a balanced environment.

Yes. They can hold cuttings while the cuttings put out roots.

They give the roots a stable, airy medium to grow into.

It depends on the plant, but many seeds germinate in 7 to 14 days. We do not claim they germinate faster than soil.

Yes. They are easy to use: soak them, put in the seeds and keep them moist.

The fibres hold water, so seeds stay moist without the cube becoming soaked.

A rockwool seed starter is versatile and can be used for a variety of plants, including vegetables, herbs, and flowers. It's ideal for hydroponic setups, where consistent moisture is critical.

Typically, rockwool starter plugs are designed for single use as they can retain salts and minerals from previous growth. Reusing may impact new plants’ health, so it’s best to use fresh plugs for each cycle.

We do not say they are better than soil. They hold moisture and air evenly and fit straight into a hydroponic system, which is why hydroponic growers use them.

Soak it in pH-adjusted water (about pH 5.5 to 6.5) for 30 minutes, then put the seeds in the holes.

Yes. They hold moisture while the roots take up nutrient from the water.

They have air spaces and hold moisture, so roots get both air and water.

Starting seeds, or rooting cuttings, in a medium that holds water and air. Hydroponic growers use it because it contains no nutrient of its own, so you control the feed.