Mulch One of the best weed-management practices to use in the landscape is mulching. Often the most effective approach is to use a combination of mulches, such as plastic covered with rock, covered with bark mulch. Blocking sunlight is important because some weed seeds will not germinate without stimulation from sunlight. Also, sunlight is critical for the new weed seedling to begin photosynthesis for growth and development. Be careful, however, that the mulch you use does not contain a large supply of weed seed.
Synthetic mulches are also available.
Black or colored polyethylene sheeting can be used as a weed barrier, but you must put irrigation lines under the sheeting, since rainfall will not penetrate this barrier. Woven synthetic landscape fabrics are also available. These fabrics eliminate the need to place irrigation lines under the fabric, but they are less effective in eliminating sunlight. Many weeds in flower beds can easily be removed by hand. Most people benefit from some exercise, and bending to pull weeds can be healthy exercise.