Putting it on gravel will also work but if you have a plastic membrane underneath, you may want to remove a section under the bin so that the bugs can get in.
Gallwch roi'r bin ar gerrig mân ond, os oes haenen blastig o dan y cerrig mân, mae'n werth gwaredu'r plastig o dan y bin er mwyn i bryfed a thrychfilod allu mynd i mewn i'r bin.