Personally I do not like membranes. The weeds grow on top of them and then are even harder to remove. Also they make ideal hiding places for all sorts of nasties. Where we had them slugs and snails proliferated underneath.
Best way is to begin with weed free soil, then mulch with at least 2 inches depth. This will not keep the weeds out, but it does make them easier to pull out as they tend to grow in the mulch.
Any sterile organic material will do. but if your soil is acidic I would avoid Pine bark or Peat.

Agree - I'd avoid membrane like the plague.

I'd stay away from those weed membranes - they look ugly, they don't work and a royal pain in the tucus in general. A couple inches of organic mulch should work, but it breaks down and you'll have to replenish every year or so. You can also go with pea gravel or slate chips. They work just fine and come in all kinds of colors and won't break down. It's kinda pricey, but will last for years and looks great esp at those summer back yard parties. It gives a stylish & formal appearance. Google pea gravel, then landscaping to get some great ideas. You'll always get that odd weed here and there, but it will be minimal work.

I too dislike membranes the soil also becomes sour to my point of view and makes it more difficult to use slow-acting fertilisers like bone meal. I would go for just of mulch of bark chippings which you can rake over from time to time and they will also break down eventually if you change you mind at a later stage.

Thank you, I almost ordered the membrane - glad now I asked before making the purchase. Again you have come up with good advice and probably saved me a headache in the future.

Yes for sure. I tried the membrane years ago and still can't get it all up. The roots grow through it and weeds grow right up through it and hold it down in places. It's a real disaster.

Agree - the only people to really benefit from membranes are the suppliers. I'm sure this question was asked before a few weeks ago?

It's interesting though isn't it that lots of the gardening makeover shows use membrane for all sorts of uses? Under decking to stop weeds, under gravel or chip paths and loads of other ways. Decking I always think harbours rats, especially in the countryside! We chucked an old carpet down in a rough area to smother years of weeds, which it did, but now is has broken down and other weeds have got embedded in the long stringy fibres and are impossible to get out, trying to pull out eight foot of nylon fibre is a nightmare - so beware!

Thank you again for your help. I have now asked a local firm to mulch it for me.