How to Prevent Crabgrass in Flowers


Crabgrass is a common problem in lawns and landscapes, and gardeners have to create a management program to keep it out of flowerbeds. Left unchecked, crabgrass can overrun a flowerbed; this will suffocate new shoots from other plants and deny them needed nutrients and sun. The prevention process begins with the effective elimination of the existing problem.

Killing the Existing Problem

Step 1

Pull out young crabgrass plants by hand. Pull the roots out with the plant by firmly grasping the base of the plant and pulling straight up from the ground. Rake older crabgrass plants opposite to the position they are laying in. Remove older plants before they go to seed. If pulling and weeding is too labor intensive, go to the next step for an alternative method.

Step 2

Cover the crabgrass with a thick layer of newspaper or black plastic. The sun and fabric will dry out the crabgrass and burn the leaves. Check under the layer after a few days for dead or wilted crabgrass. Remove the plastic or paper. Rake the crabgrass; it will be much easier to remove when it's dried out.

Step 3

Rototill the flowerbed to dig up any remnants and roots left behind from previous seasons. Rake the top of the soil to remove the debris. Lay clear plastic over the area. Leave the plastic in place up to eight weeks; this allows the sun to dry out any remaining crabgrass seeds so they do not germinate.


Step 1

Lay synthetic landscaping fabric over the flowerbed. This keeps new weeds from seeding or emerging in the flowerbeds. Set landscape rock or tile around the edges to keep the fabric sides from getting stray ends. This covering remains in the flowerbed and is not removed unless it is torn or damaged.

Step 2

Lay a natural ground cover over the fabric to help reduce wear on the fabric and compliment the flowers. Use a 3 to 6 inch layer of material such as mulch, wood chips, nuggets, composted yard material or gravel. Create a hole in the ground cover where the flowers will go; cut an "X" in the fabric below to plant the seed. Allow the flowers to grow up through the covering. Check the ground cover annually to see if any sections need replacing due to decomposition or displacement.

Step 3

Use the edger to create an edging between the turf and flowerbed. Edging helps eliminate the chance of seeds gathering along the sides of the flowerbeds and will keep crabgrass in the lawn from invading the flowerbeds.

Things You'll Need

  • Landscape fabric
  • Rake
  • Landscape tile or stone
  • Mulch
  • Wood chips
  • Herbicides
  • Clear plastic


  • North Carolina State University: Weed Management in Annual Color Beds
  • University of California: How to Manage Pests - Pests in Gardens and Landscapes - Crabgrass
Keywords: crabgrass in flowers, preventing crabgrass, flowerbed maintenance

About this Author

Jack S. Waverly is a Pennsylvania-based freelance writer who has written hundreds of articles relating to business, finance, travel, history and health. His current focus is on pets, gardens, personal finance and business management. Waverly has been writing online content professionally since 2007 for various providers and websites.