Types of Weeds

• There are three main types of weeds you can encounter in the garden: grassy, broadleaf and sedge weeds. Grassy weeds such as crabgrass easily invade garden beds from the lawn. Look at the tips of the grass blade to see if the weed in question is grass. Grassy weeds have triangular tips. Broadleaf weeds are more colorful than grassy or sedge weeds. Sedge weeds look like grass, but have rounded tips. Use herbicides that are chemically formulated to kill the specific type of weed.
  
  

Digging and Mulch

• Digging up weeds gives gardeners the peace of mind that they are not spraying chemicals that can harm their vegetables, plants or ornamental flowers. Certain types of weeds such as dandelions have deep tap roots, which are difficult to remove. To dig up plants and remove their entire root systems, press a shovel 2 inches away from the base of the plant. Dig at least 6 inches deep and push the entire root system through the soil. Spread a 2- to 4-inch layer of mulch in the former weed area to prevent new weeds from cropping up.
  
  

Herbicide

• Gardeners can use a selective herbicide to control grassy and sedge weeds in their garden. Using a selective broadleaf herbicide is too risky, because it can kill your desired plants. Use a selective herbicide that contains fluazifop, quinclorac or sethoxydim plus oil, as recommended by the University of California. Check the label to ensure that it will not harm the surrounding plants. Water your grassy and sedge weeds for several days before applying the herbicide. Vigorously growing weeds are easier to kill with herbicide.
  
  

Broad Spectrum Herbicide

• Broad spectrum herbicides kill any type of vegetation including your ornamental plants. However, broad spectrum herbicides leave little soil residue, so gardeners can plant right after weeds die from the spray. You can safely use broad spectrum herbicides by dipping a small paintbrush into the herbicide and painting the chemicals on the weed's foliage. Be sure to choose a dry day, because the herbicide needs at least 24 hours to soak into the plant.