Question
We have a rock area whose weed barrier failed, so while preparing it for new we discovered there is a blend of different levels of concrete and some dirt underneath.   We have a plastic weed barrier but are concerned that with rocks on top and concrete underneath it will fail quickly.  Are we correct in our concerns?  Would wood mulch be a better choice?  It would be within 30" of our house.  And of course, we would like an economic solution.  Thank you.

Answer
See my previous answers about weed barriers. I don't believe in them. They are gimmicks that always fail as organic material breaks down and covers them from above (wind and water carried) the weeds grow in the soil above and root right through the weed barrier. If you are using straight plastic, as a weed barrier, don't that is bad for the environment as no water get through to soil below which is needed for many reasons. Besides over a short period of time the plastic begins breaks down from UV exposure and starts coming up through anything you put over it. Eventually it looks very bad. Professional landscapers with any education and quality in mind will never use plastic.  Your best bet is always a good thick layer of mulch of any type you like. 3 to 4" thick is generally good, but you may need to top it off each year as some of it always breaks down.

Nothing in the landscape is ultimately maintenance free. You may have to weed occasionally but if you stay on tip it gets easier each year. Add more mulch and some pre-emergent weed preventative each spring for best results.