Can I put my surplus hydroponically-grown seedlings into soil?

Yes, that's not a problem.   Hydroponically-grown seedlings can be transplanted into soil in exactly the same way as soil-grown seedlings.  As with all transplanting, carefully loosen the seedling from its pot or tray using a dibber or pencil, holding the plant by its leaves and not its stem.  Make sure the hole into which you're transplanting is big enough so as not to damage or squash the seedling's root system.  Place the seedling into the hole, making sure that it is at the same level as it was in its previous home, and gently firm the soil around it.  Using a watering can with a fine rose spray, water the seedling to settle the roots.

It is quite common to have a surplus of plants once you have filled your hydroponic systems so at The Achiltibuie Garden we recommend either planting them in soil or maybe give to friends.

If you have grown cuttings in Gold, it is also possible to transfer them into soil or compost.