Sowing depth of seeds

On the back of our seed bags we always try to write what sowing depth the seed should have when sowing. If the seeds are light-germinating, we mention this, which means that the seed should not be covered with soil, but the seed needs light to germinate. However, it is important when sowing light-germinating seeds that it does not have time to dry out. Since it lies on the surface and has no moist soil around it, it can therefore dry out more easily. We recommend and always use a thin layer of Vermiculite over light-germinating seeds. The light passes through and it binds moisture, which helps to keep the seed moist on the surface.

How deep should the seed be planted?

• The size of the seed usually determines how deep it should be sown.
• The smaller the seeds, the thinner the layer of soil needed, or none at all.
• Very small seeds are usually light-germinating and should not be covered at all, while larger seeds should be planted deeper.
• You can often aim for seeds to be sown about twice as deep as the size of the seed.
• A seed is loaded with all the nutrients it needs to germinate, until it reaches the surface and gets its first cotyledons, which then convert light into nutrients to create the characteristic leaves.
• If you plant the seed too deep, it will not have time to reach the surface and form leaves before the seed's stored nutrients run out and the seed dies.