How to remove stubborn stains from artificial grass

Act quickly — and remove as much of the spillage as possible before it begins to harden.
Soak up any liquids with a clean cloth, kitchen towel or (if you have some to hand) cat litter — all of these will absorb any liquid.
If there is still a mark, mix a small amount of washing up liquid and lukewarm water together. Apply with a synthetic bristled brush or a clean cloth or sponge.
Work the solution in between and around the stained fibres. Rinse the area thoroughly with water from a garden hose or watering can.
If the spillage has hardened, you may need to carefully remove it using either a plastic spatula or plastic knife. You could also try using a toothbrush to gently brush the stain away.