Hi MK.
There are a number of pros and cons for newspaper as mulch/weed block. Newspaper is often used in lasagna gardening, a method of getting a new area ready to plant. It smothers weeds, grass and seeds by blocking air, light and water. Only the plain newsprint should be used, not the glossy, colored ink ads.
http://everydaygardener.com/th...
If there is nothing growing in an area used for vegetables /annuals in the spring, then a layer of newspaper 2 or 3 sheets thick could be used under a couple inches of leaves, straw or bark mulch to keep weeds from growing over the fall/winter and weed seeds from sprouting in the spring. The newspaper will start breaking down and can be tilled into the soil when you are ready to plant.
Shredded newspaper can be used as a base under regular mulch to help extend the coverage area. Just remember, layers of unshredded newspaper more than a couple sheets thick will take a long time to break down and will not allow rain /water to reach the plants' roots when used in existing annual/perennial beds.
http://www.savvyhousekeeping.c...
My husband wanted to surprise me while I was away. He covered a bed with newspaper and mulch. The paper was about 8 sheets thick with about 3 inches of pine mulch over it..something I discovered when the Japanese magnolias started blooming, but not a single daffodil or hyacinth had broken dormancy. When I started investigating, some of the bulbs were stunted, some trying to grow parallel to the ground and some were just shriveled and dead. The rainwater soaked through the mulch, but rolled off the thick layers of paper.
I hope this helps.
