Cardboard
The moment you have planted your garden, you will then be ready to lay the mulch down. However, right before you proceed to doing that, include a protective measure that will keep your garden safe from stubborn weeds. Get some cardboard pieces and lay them right on the ground around your plants before you go ahead and put down the mulch. Ensure this mulch is well laid over the cardboard, which will in turn block any weeds from growing.