Landscape mats, however, can be used around trees and shrubs as these materials allow water and air to pass through them. The landscape mats should be placed on the ground and then covered with wood chips or shredded bark. Herbicides can be used to help control weeds in the home garden. Cultivation, hand pulling, and mulches should be considered the primary means of weed control. Herbicides can be used to supplement these methods.
Several limitations prevent their extensive use in the garden.
Different herbicides often have to be applied to the various crop areas. Both products are preemergence herbicides. They must be applied before the weeds germinate. Emerged weeds need to be eradicated prior to application. Dacthal can be used on yarrow, ageratum, snapdragon, columbine, aster, chrysanthemum, coleus, cosmos, dahlia, bleeding heart, purple coneflower, gladiolus, baby's breath, iris, lily, nasturtium, peony, geranium, petunia, rose moss, rose, sedum, marigold, and zinnia.