Garden surfaces and cliffs
Tertill works most efficiently when the terrain in your garden is relatively smooth. Tertill will do its best when it encounters rocks, ruts, and holes but any time it spends negotiating such hazards is time it won’t spend weeding. We recommend removing rocks as much as possible and raking at the beginning of the season to smooth the garden surface.
A wide variety of surface types are acceptable to Tertill. This includes bare dirt both soft and packed, sand, gravel, bark mulch and other materials commonly used in gardens.
Tertill does not sense cliffs. A cliff is any drop off over which Tertill cannot safely drive. Terraced gardens, for example, have cliffs. If your garden contains a cliff it should be blocked off with a fence or the supplied row collars. Otherwise Tertill may topple.