An artefact 1 for the preparation of a grass-covered area comprises a roll of flexible sheet material 2 impregnated with grass seed 3. The flexible sheet material 2 comprises peat and/or other organic growth-promoting substances and the grass seed 3 may be evenly impregnated below the surface of the material 2 to frustrate attempts by birds to consume the seed, when the material is laid. The sheet material 2 is covered with an opaque plastics material 4 which, by the exclusion of light and/or moisture, at least retards premature germination of the grass seed 3, until the covering material 4, e.g. black coloured polythene, is stripped from the base material 2. The material 4 could be applied to each side of the sheet material 2, or as a total wrapping of a roll.
