Remove all weeds and weed roots before you plant. Before planting new perennials, be certain there are no weeds growing among them in the containers. After planting, apply a three-inch layer of organic mulch to help prevent new weeds from growing. Make sure the mulch does not touch the trunk or main stem of the plants. Hand-pull weeds near established plants before the weeds flower and produce seed.
Herbicides can be useful in managing persistent weeds.
Some will kill weeds selectively without harming ornamental plants. Others kill all plants either by contact with the foliage or through the root system. If you are considering using a herbicide, carefully read and follow all label directions. Be sure that you select the product intended for the weeds you want to control and use it properly so that you do not injure your ornamental plants. During the growing season, rake and remove excess leaves, twigs, spent blossoms, fruit, or seed capsules that have fallen from your trees and shrubs.