Starting a patch from scratch

I wouldn't use membrane either. Just get cardboard, and cover it with one or two inches of compost or manure, whatever you have. That's it. Sow or plant into it

I did that on a grassy patch around the summer house and planted my garlic there. Thick card, horse manure, garlic straight in. They're about 10cm tall now. The only weeds are in the corners so far.

I will use that method in every place I can in the garden where I will grow veggies or flowers, whether from seed, seedlings or fully grown plants.