After this summer, it's become apparent that I need to mulch my blueberry patch (after I dig them out from under the morning glories). I planted them in what used to be "lawn", so I think grass will be an issue as well. What would be the best mulch to use, something I can use in a heavy layer to smother the unwanted intruders. I've considered several alternatives, but thought I'd ask people with more experience before deciding :)
To humor my laziness, I just use the pine mulch bags from Lowe's, I think its $3.99 per bag. Pine bark (or pine straw) gives you the acid that blueberries love. I don't know about smothering weed (i.e. morning glories) or grass with just the pine bark. I still have some left over plastic mesh Lowe's sells for weed suppression under mulch and it works well for me.
I have used local gathered pine straw for years. Its not as big and wiry as the baled pie straw I bought from a hardware store in NC this spring, but a local white pine tree. Anyway- thick enough it can suppress some weeds. I still have a creeping grass get under it, lightly, and godawful morning glories. (an idiot I saw letting them grow all over the bushes one year) But nothing else new seems to sprout under it.