I don't know what kind of vegetables you are growing, but I often put mulch down and get it right up to the plants, when they are large enough. Many seedlings of weeds are simply smothered. At times I have even taken the bags of raked up leaves that people leave on the roadside and they work fine.My friend uses the large amounts of grass clippings he gets from the large area he mows.

Mulching will certainly help to smother out any annuals , but will assist any spreading perennials like Calystegia or Convolvulus to form larger roots...

Good Luck (!)