What is the best material to use in a latex garden mould?

Question

i have recently got 1 and have not got a clue what to use plaster or sand and cement.

Answer 1

If you want to make something that will go outdoors, use concrete.  Get some portland cement and some sand; mix 3 parts sand and 1 part cement.  Add enough water to make it like muffin batter.  Plop it into the mold which you have sprayed with Pam.  (Wear gloves)  Shake it to settle it and get the bubbles up to the top.  Allow it to sit for a day or so before you remove the mold.  Let it cure for a week after that.