Mulching your garden helps in many ways:
-Mulch protects the soil from eroding
-Mulch reduces soil compaction
-Mulch conserves water
-Mulch keeps soil temperature more level
-Mulch improves soil as it decomposes
-Mulch prevents weeds
-Mulch keeps you from sinking in the mud
-Mulch looks nice
In the vegetable garden:
Try using grass clippings, newspaper, leaves, hay or straw.
In the flower beds:
Try bark, pine needles which also increase acidity of the soil, and leaves.
Mulches are best applied late spring after soil has had a chance to warm up. They should be 2″-4″ deep, excepting for newspaper which should be no more than a few sheets thick.
Pine bark mulch is a much better choice than hardwood mulches, at least in the Houston area. The hardwood mulches are made from native oaks and scrub brush. Over time they get a white fungus on the chips. This fungus is hard, which makes it hard for the mulch to absorb and hold water. It is also steals nutrients from the soil that should be going to your plants. You can usually identify hardwood from softwood mulches just by looking for the white mold on the chips.