Where are you located? Our forum members in the desert southwest swear by landscape fabric but it's a nightmare here in the mid Atlantic. I'd use river rock without the fabric beneath it.

Sorry, I’ve edited my post to show where I am located, in CT zone 6. Thanks for the input. I’ve never used it, but have heard many times that it will break down and result in a shredded mess in time. For some reason pro designers still recommend it. This is not the first time I’ve had it specified, and I skipped it before, too.

A 4"layer of river rock sounds good but for us East Coaster's it's bound to catch organic material. What do pro's/people with more experience think about using a layer of granite dust under the rocks, instead of fabric -- would that be any better?

PA. I've used river rock with landscaping fabric under. It was the best at keeping weeds out with the least amount of mantaince. 1-3 inch rock is too small IMO. We had rock the size of baseballs at the minimum. You want rock that a leaf blower will not move. All we did to maintain it was blow out any debris once in a while. Especially the fall leaves.

Wood mulch only keeps weeds down to a certain degree and you have to replace it every year. If on a slope, it will wash out. I only use it in beds I am waiting for the perennials to fill in or I plant annuals every year.

This will be inside a pool fence enclosure with minimal (hopefully) leaves close enough to make a mess, but there will surely be some debris that blows in.