crabgrass

Large crabgrass (Digitaria sanguinalis)
Photo: Betty Marose

Updated: June 10, 2022

Quick tips for managing common lawn weeds

  • A healthy, dense, vigorous lawn is the best defense against common lawn weeds. Research shows that mowing fescue lawns to 3-4 inches and seeding bare spots will reduce crabgrass infestations. Practices that significantly reduce weeds in lawns include:
  • Identify the weed. This is very important in determining what the next step should be. 
  • Weeds like nutsedge (soil too wet) and common lespedeza (dry, infertile soil) can indicate that growing conditions are poor for grass growth. Moss does not kill grass but moves into shady, moist areas where the grass has thinned out. If poor growing conditions (e.g., low sunlight, poor drainage, acidic and compacted soil) cannot be improved to favor turfgrass, weeds will continue to be a problem.
  • Regular mowing can help reduce weeds that spread from seed. Mow dandelions when they are flowering to prevent them from going to seed.
  • Weeds can be spotted treated with OMRI Listed® organic herbicides instead of conventional herbicides. 

Common lawn weeds

Broadleaf winter annuals

Seeds of these weeds germinate from late summer through fall. Plants overwinter and continue to grow in early spring.

  • chickweed with tiny white flowers

    Chickweed

    Photo: Dr. Kevin Mathias, UMD (retired)

  • deadnettle flower closeup

    Deadnettle

  • hairy bittercress flowers and seed pods

    Hairy Bittercress

    Photo: Betty Marose

  • closeup of henbit leaves

    Henbit

    Photo: Dr. Kevin Mathias, UMD (retired)

  • knawel closeup

    Knawel

  • shepherds purse flowers and seed pods

    Shepherd's Purse

    Photo: Mary Ellen (Mel) Harte, Bugwood.org

  • speedwell foliage

    Speedwell (Veronica spp.)

    Photo: Betty Marose

Grassy winter annual 

Seeds germinate in late summer to early September.

  • annual bluegrass weed with flowers

    Annual Bluegrass

    Photo: University of MD Extension

Broadleaf summer annual weeds

Weed seeds begin to germinate as soils begin to warm up in early spring and continue to germinate throughout the growing season. Annual lawn weeds complete their entire life cycle in a single growing season. However, some of these weeds can also be perennials or biennials (produce leaves the first year and flower the second year).

  • yellow flowers of black medic plant

    Black Medic

    Photo: Karan A. Rawlins, University of Georgia, Bugwood.org

  • carpetweed

    Carpetweed

    Photo: Debra Ricigliano, HGIC

  • lespedeza

    Common Lespedeza or Japanese Clover

    Photo: Rebekah D. Wallace, University of Georgia, Bugwood.org

  • common mallow

    Mallow

     Photo: Betty Marose

  • prostrate spurge

    Prostrate Spurge

  • purslane

    Purslane

Grassy summer annual weeds

Seed germination begins in early to mid-spring, when soil temperatures have risen to 55° - 60° F. for about a week. In Central Maryland; this is typically mid-March through mid-April. Seeds of common home weeds continue to germinate in the summer, and plants are killed by the first frost.

  • crabgrass

    Crabgrass

    Photo: Betty Marose

  • goosegrass

    Goosegrass

    Photo: Betty Marose

  • Japanese stiltgrass seedlings

    japanese stiltgrass

    Photo: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

Broadleaf perennial weeds 

Perennials are persistent from year to year. They reproduce by seed and also by vegetative means. This is the largest group of weeds. They range from weeds that are easy to eliminate, to some of the most difficult to manage.

  • immature dock

    Broadleaf and curly dock

    Immature dock foliage

  • plantain

    Broadleaf plantain

    Photo: Betty Marose

  • bulbous buttercup flower

    Buttercup

  • cinquefoil

    Common Cinquefoil

    Photo: David Stephens, Bugwood.org

  • dandelion

    Dandelion

     Photo: Betty Marose

  • light purple ground ivy flowers

    Ground Ivy (creeping Charlie)

    Photo: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

  • Indian mock strawberry

    Mock Strawberry

    Photo: Betty Marose

  • oxalis

    Oxalis (wood sorrel)

  • red sorrel foliage

    Red Sorrel (sheep)

    Photo: Theodore Webster, USDA Agricultural Research Service, Bugwood.org

  • clover

    White Clover

    Photo: Betty Marose

  • wild garlic or wild onions

    Wild Garlic and Onion

    Photo: Betty Marose

  • wild violet

    Wild Violet

    Photo: Betty Marose

Grassy perennial weeds

These are some of the most difficult weeds to control in a lawn.

  • area full of bermudagrass weeds

    Bermudagrass or wiregrass

    Photo: David J. Moorhead, University of Georgia, Bugwood.org

  • how dallisgrass looks in a lawn

    Dallisgrass

    Photo: John D. Byrd, Mississippi State University, Bugwood.org

  • weedy nimblewill in a lawn

    Nimblewill

    Photo: Ohio State Weed Lab, The Ohio State University, Bugwood.org

  • orchardgrass

    Orchardgrass

    Photo: Dr. Kevin Mathias, UMD

  • quackgrass

    Quackgrass

    Photo: University of Maryland Extension

  • Roughstalk bluegrass. Photo: Mira Talabac, University of Maryland Extension

    Roughstalk Bluegrass

    Photo: Miri Talabac, University of Maryland Extension

Sedges

These plants are not grasses or broadleaf weeds.

  • green kyllinga

    Green Kyllinga

     Photo: NC State University 2005

  • yellow nutsedge

    Yellow Nutsedge

    Photo: HGIC, U of MD Extension

Moss

Technically, is not a weed but sometimes people consider it to be.
It is actually an attractive groundcover in areas where grass does not grow well or is planted and maintained as a lawn alternative.

Moss in Lawns

Moss in the Landscape

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