Ten (10) litre bag of vermiculite. Vermiculite has excellent water holding capabilities makes it an excellent addition to sandy soils or dried out ground.
Vermiculite is a natural sterile soft mica mineral with great water holding and insulation properties. It also offers a high cation exchange capacity which means it will slowly release nutrients back to your plant which it has absorbed during watering.
We use it for propagation. It is sprinkled over the surface of seeds, misted and then covered with a lid. Vermiculite is easy and safe to handle and odourless whilst also being lightweight and simple to use.