WEED CONTROL
By Leslie E. Stevens UCCE Master Gardener
What can I do to reduce weeds in my landscape? Carol K. SLO
Rainfall's welcome return brings lusher landscapes and spring blossoms to our gardens. It also spawns a bumper crop of noxious invaders commonly known as weeds. Left unattended, these uninvited guests can overwhelm your prized plantings, sucking up more than their share of water and nutrients, and otherwise damaging your garden's health and appearance.
Weeds by nature tend to be highly tenacious and adaptable, requiring a multi-pronged and ongoing effort to control and eradicate. Primary tools for home gardeners include cultural practices, mechanical and physical methods, and chemicals as a last resort.
Cultural: Proper soil preparation, irrigation methods, suitable plant selections and timing are examples of cultural considerations that can have big impacts on your garden's overall success and ability to outcompete weeds. Consider laying sod rather than planting seed for a new lawn. Choose plants that fill in quickly and are well adapted to your environment. Plant more densely to discourage weed growth. Avoid sprinklers where feasible. Instead, install drip irrigation to direct water to desirable plants' roots where it's needed, thereby reducing water consumption and minimizing damp ground where weeds easily can take root.
Mechanical: Time-tested methods of eliminating existing weeds include hoeing, hand-pulling, rototilling, mowing and chopping.
Physical: Soil sterilization prior to planting provides a head-start in preventing existing seeds from germinating. Likewise, spreading mulches around existing plants makes it more difficult for weed seeds to germinate by blocking sunlight and preventing seedlings from growing through the mulch barrier. Mulches also have the added benefits of conserving moisture and moderating soil temperature.
Your best chance of combating weeds is to inspect your landscape regularly and attack the intruders before they get a chance to become established. Good hunting.
Resources:
UCCE Weed Research & Information Center, http://wric.ucdavis.edu/information/info_spec_weed.htm
Weed Management in Landscapes, http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7441.html
Weed Management in Lawns, http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74113.html