My lovely kittens are pooing on my lawn

[MrsCampbellBlack]

Naughty kittens (they're just over 6 months)- both just started going outside as have had their little operations and are pooing outside.

However they just seem to be pooing on my lawn rather than in the dirt and covering it up so how do I encourage them to stop doing this.

Also have the fear they'll start pooing on my neighbour's lawn!