Which Lawn Weeds Have Yellow Flowers?

Common lawn weeds with yellow flowers include:

• Black medic (Medicago lupulina)
• Buttercup (Ranunculus spp.)
• Cat's-ear (Hypochaeris radicata)
• Dandelion (Taraxacum officinale)
• Celandine (Chelidonium majus)
• Creeping cinquefoil (Potentilla reptans)
• Hawk’s beard (Crepis spp.)
• Ragwort (Senecio jacobaea)
• Mouse-ear hawkweed (Hieracium pilosella)
• Yellow clover (Trifolium dubium)

Conquer weed issues by mowing at the ideal height and implementing judicious watering and fertilization to promote robust grass health. Use mulch to discourage weed growth and opt for selective herbicides for precise control. Consistently monitor and promptly eliminate weeds, aligning with a comprehensive lawn care regimen for effective weed management.

Though some yellow lawn weeds may seem charming, they compete with your turf for nutrients, sunlight, and water. Their aggressive spread can overwhelm grass, hindering its growth. So, if you find yourself dealing with a yellow weed invasion, what's the best approach? Continue reading to learn more.

Identifying Lawn Weeds with Yellow Flowers

Black Medic (Medicago lupulina)

Black medic is a low-growing annual or perennial weed with distinctive yellow flowers, often found in lawns and disturbed areas. It typically forms prostrate mats close to the ground, with compound leaves consisting of three leaflets. The stems can sprawl or ascend, and the plant features clusters of small yellow flowers.

Black Medic Characteristics

Appearance: This low-growing weed features clover-like leaves and clusters of small, yellow flowers.

Habitat: It thrives in sunny locations, making lawns susceptible to infestations.

Life cycle: Annual or perennial. Produces seeds and spreads through creeping stems. Its ability to form dense patches can impact the aesthetics and health of lawns.

Control Strategies for Black Medic 

Management of black medic involves cultural practices, such as regular mowing, to weaken the plant. Manual removal is effective for small infestations. 

Selective pre and post-emergent herbicides: Selective herbicides designed for broadleaf weed control may be considered for more extensive control.

• Cool-season lawns — Tenacity Herbicide 
• Warm-season lawns — Specticle FLO (pre-emergent) / Celsius and Certainty Herbicide Kit with Surfactant and Dye
• Cool and warm-season lawns — Triad Select™ Herbicide

 

Buttercup (Ranunculus spp.)

Buttercups exhibit various growth forms, including annuals, perennials, and herbaceous or woody plants. The most common species feature glossy yellow flowers with distinctive petal-like sepals. Despite their charming appearance, many buttercup species contain toxins that can be harmful to livestock if ingested.

Buttercup Characteristics

Appearance: Buttercup flowers are characterized by their five petal-like sepals. The vibrant yellow color and shiny appearance give them a buttery glow, inspiring the common name.

Habitat: Commonly found in moist, fertile soil, but can adapt to various conditions.

Life cycle: Annual or perennial. Reproduces through seeds and creeping roots.

Control Strategies for Buttercups

Management of buttercups involves cultural practices, such as regular mowing, to weaken the plant. Manual removal is effective for small infestations. 

Improve soil drainage: Buttercups often thrive in moist conditions. Improve soil drainage by addressing any waterlogged areas in your lawn.

Fertilize appropriately: Conduct a soil test and fertilize your lawn according to its needs. Ensuring the grass is healthy and robust can help it compete with buttercups.

Selective post-emergent herbicides: Selective herbicides designed for broadleaf weed control may be considered for more extensive control.

• Cool-season lawns — Tenacity Herbicide
• Warm-season lawns — Celsius and Certainty Herbicide Kit with Surfactant and Dye

 

Cat's-Ear (Hypochaeris radicata)

Cat's-ear is a perennial weed resembling dandelions, known for its distinctive yellow flowers and basal rosette of leaves. The plant typically grows close to the ground, and the stem exudes a milky sap when broken.

Cat’s-Ear Characteristics

Appearance: Easily mistaken for dandelions but has hairy leaves. Yellow flowers appear on tall stems.

Habitat: Thrives in well-drained soil, often invading lawns and disturbed areas.

Life cycle: Perennial. Spreads through seeds and a deep taproot.

Control Strategies for Cat’s-Ear

Managing cat's-ear involves cultural practices such as regular fertilization and manual removal. Ensuring a healthy and well-aerated lawn can help discourage its growth. Don’t be tempted to manage cats-ear with your lawn mower as it can stimulate flower production, and multiply the number of flowers produced, especially if cut too low.

Selective post-emergent herbicides: Selective herbicides designed for broadleaf weed control may be considered for more extensive control, but several applications may be required to eliminate it completely.

• Cool-season lawns — Tenacity Herbicide
• Warm-season lawns — Celsius® WG / Specticle FLO (pre-emergent)

 

Dandelion (Taraxacum officinale)

Dandelions are iconic and resilient perennial plants with distinctive yellow flowers and a well-known seed head that transforms into "blowballs."

They feature a basal rosette of deeply toothed, lance-shaped leaves and a hollow stem that supports a bright yellow flower head. The plant can grow in a wide range of environments and is adaptable to various soil conditions.

Dandelion Characteristics

Appearance: Dandelions are renowned for their spherical seed heads, also known as "blowballs" or "clocks," which consist of numerous parachute-like seeds attached to a central receptacle. When the wind or a gentle breath disperses these seeds, they are carried over considerable distances.

Habitat: Adaptable to various conditions, from lawns to meadows. They prefer full sun but can tolerate some shade.

Life cycle: Dandelions are perennial plants, regenerating each year from a deep taproot. While they reproduce through seeds carried by the wind, their resilience lies in the ability of the taproot to sprout new growth.

Control Strategies for Dandelions

Managing dandelions involves cultural practices such as regular mowing, ensuring a well-aerated lawn, and manual removal.

Selective pre and post-emergent herbicides: Use a post-emergent herbicide specifically designed for broadleaf weeds, containing ingredients like 2,4-D or dicamba.

• Cool-season lawns — Tenacity Herbicide
• Warm-season lawns — Celsius and Certainty Herbicide Kit with Surfactant and Dye / Specticle FLO (pre-emergent)

 

Celandine (Chelidonium majus)

Celandine is a perennial herbaceous plant recognized for its distinctive yellow flowers, lobed leaves, and bright orange sap.

It typically grows upright, reaching heights of up to two feet. The plant features pinnately lobed leaves with a hairy texture, producing clusters of bright yellow flowers.

Celandine Characteristics

Appearance: The yellow flowers of celandine have four petals and are arranged in loose umbels. They bloom in spring and early summer. One of the most notable features of celandine is its bright orange sap, which is released when the stem or leaves are broken. While visually striking, the sap can cause skin irritation and should be handled with care.

Habitat: Flourishes in shaded areas, lawns, and disturbed soil.

Life cycle: Perennial. Produces seeds and spreads through rhizomes.

Control Strategies for Celandine

Ensuring a well-aerated garden or lawn and minimizing soil disturbance can help control its growth.

Non-selective herbicides: Celandine is impossible to control using a selective herbicide. Weed killers containing MCPA may have some effect. But the only way to treat this weed effectively using a weedkiller is to use a non-selective spot spray.

• Roundup QuikPRO (note that this weedkiller will also kill your grass, so you should apply this very carefully directly to the weed).

 

Related: How to Kill Weeds Naturally

 

Creeping Cinquefoil (Potentilla reptans)

Creeping cinquefoil is a low-growing perennial weed with creeping stems, palmately compound leaves, and bright yellow flowers. It typically forms a prostrate habit, with long, creeping stems that root at nodes, allowing the plant to spread horizontally.

Creeping Cinquefoil Characteristics

Appearance: The bright yellow flowers of creeping cinquefoil have five petals and bloom in clusters at the end of stems. The flowering period occurs during late spring and into summer, contributing to the plant's ornamental appearance.

Habitat: Invades lawns, gardens, and open spaces. It thrives in well-drained soils and can tolerate a range of moisture conditions.

Life cycle: Perennial. It reproduces through both seeds and vegetative growth, forming dense mats of foliage.

Control Strategies for Creeping Cinquefoil

Creeping cinquefoil is moderately resistant to many selective herbicides. In most cases, two applications (about six weeks apart) will be required for effective control.

Selective post-emergent herbicides: Selective herbicides designed for broadleaf weed control may be considered for more extensive control

• Warm-season lawns — Use selective herbicides for perennial broadleaf weed control, which include the ingredient dicamba like Celsius® WG.
• Non-selective herbicide — Roundup QuikPRO (note that this weedkiller will also kill your grass, so you must apply this very carefully directly to the weed).

 

Hawk’s Beard (Crepis spp.)

Hawk's Beard comprises a genus of flowering plants, Crepis, known for their dandelion-like appearance and distinctive pappus-tipped seeds — a structure that aids in wind dispersal. When mature, the seeds are carried by the wind, allowing the plant to colonize new areas.

Hawk’s Beard Characteristics

Appearance: Resembles dandelions, with numerous yellow ray florets surrounding a central disk. The flowers are borne on tall, slender stems and bloom during the spring and summer months.

Habitat: Common in lawns, meadows, and disturbed areas.

Life cycle: Perennial. They reproduce through both seeds and vegetative growth, forming colonies that can be challenging to control.

Control Strategies for Hawk’s Beard

Manual control: Wear gloves and use a weeding tool to manually remove hawksbeard, ensuring you pull out the entire root system.

Mulching: Apply a thick layer of organic mulch around desirable plants to suppress hawksbeard growth and prevent sunlight from reaching the soil.

Selective post-emergent herbicides: Use a post-emergent herbicide containing 2,4-D or dicamba. Hawksbeard is persistent, and multiple treatments may be necessary. Be patient and consistent in your control efforts.

• Cool and warm-season lawns — Triad Select™ Herbicide 

 

Ragwort (Senecio jacobaea)

Ragwort is a biennial or short-lived perennial plant that can reach heights of 1 to 2 meters. It often forms a basal rosette in the first year, producing a flowering stem in the second year.

It contains alkaloids that can be toxic to livestock if ingested. It is considered a noxious weed in some regions due to its potential impact on animal health.

Ragwort Characteristics

Appearance: The bright flowers are daisy-like but fully yellow, with multiple ray florets surrounding a central disk. They form dense clusters at the ends of branched stems and bloom during the summer months.

Habitat: Common in lawns, pastures, and disturbed areas.

Life cycle: Biennial or perennial. Produces abundant seeds which are wind-dispersed.

Control Strategies for Ragwort

Manual removal: Wear gloves and use a weeding tool to manually pull out ragwort, ensuring you remove the entire root system. Dispose of the plants carefully. Be aware of legal requirements related to ragwort control in your region. In some areas, there may be specific regulations regarding its removal due to its toxicity.

Biological control: Introduce biological control methods, such as releasing ragwort flea beetles (Longitarsus jacobaeae), which feed on the plant. Ensure that the introduction of biological controls complies with local regulations.

Improve soil health: Ragwort often thrives in nutrient-poor soil. Improve soil health by adding organic matter and fertilizing appropriately to make the area less favorable for ragwort growth.

Selective pre and post-emergent herbicides: Apply pre-emergent herbicides in the fall to disrupt the life cycle of seeds, minimizing the chance of infestations.

• Cool and warm-season lawns — Triad Select™ Herbicide 
• Warm-season lawns — Specticle FLO (pre-emergent) / Celsius® WG.

 

Mouse-Ear Hawkweed (Hieracium pilosella)

Mouse-ear hawkweed is a low-growing perennial herbaceous plant from the Asteraceae family. The basal leaves are spoon-shaped and covered with fine hairs, giving them a fuzzy or "mouse-ear" appearance. The stem leaves are lanceolate and arranged alternately.

Mouse-Ear Hawkweed Characteristics

Appearance: Small, yellow, dandelion-like flowers with multiple ray florets surrounding a central disk. They bloom in clusters at the end of stems during late spring and summer.

Habitat: Common in lawns, meadows, and open fields. It thrives in well-drained soils.

Life cycle: As a perennial plant, Mouse-Ear Hawkweed regrows each year from a system of rhizomes. It reproduces through both seeds and vegetative growth.

Control Strategies for Mouse-Ear Hawkweed

Regular mowing: Maintain regular mowing to keep the grass at a height that shades the soil, making it less favorable for mouse-ear hawkweed growth.

Vinegar solution: Mix vinegar with a small amount of dish soap and spray it on mouse-ear hawkweed. The acidity can be effective, especially on sunny days.

Selective pre and post-emergent herbicides: Use a post-emergent herbicide containing 2,4-D or dicamba.

• Cool-season lawns — Tenacity Herbicide
• Warm-season lawns — Celsius and Certainty Herbicide Kit with Surfactant and Dye / Specticle FLO (pre-emergent)
• Cool and warm-season lawns — Triad Select™ Herbicide 

 

Yellow Clover (Trifolium dubium)

Yellow clover is a low-growing herbaceous plant from the legume family (Fabaceae). It typically forms a prostrate or ascending growth habit.

The leaves are trifoliate, consisting of three leaflets. The leaflets are oval to heart-shaped and often have a pale V-shaped mark. Like other clovers, it has nitrogen-fixing capabilities, contributing to soil fertility. 

Yellow Clover Characteristics

Appearance: The flowers are small, pea-like, and yellow. They are borne in compact, spherical clusters at the ends of stems. Flowering occurs during the spring and summer months.

Habitat: Adapts to various soil conditions, invading lawns and open areas. It prefers well-drained soils.

Life cycle: Yellow clover is typically an annual or short-lived perennial plant. It reproduces through seeds, and a single plant can produce numerous seeds.

Control Strategies for Yellow Clover

Selective pre and post-emergent herbicides: Apply pre-emergent herbicides in the fall to disrupt the life cycle of seeds, minimizing the chance of infestations.

• Cool-season lawns — Tenacity Herbicide
• Warm-season lawns — Celsius and Certainty Herbicide Kit with Surfactant and Dye / Specticle FLO (pre-emergent)
• Cool and warm-season lawns — Triad Select™ Herbicide 

 

Related: The Best Four Products for Killing Weeds Without Killing Grass

 

Caring For Your Lawn Is The Best Way to Tackle Weeds

A well-cared-for lawn is essential in thwarting the spread of yellow-flowered lawn weeds. 

• Regular mowing at the correct height deprives weeds of sunlight, hindering their growth. 
• Proper watering sustains the health of desired grasses, creating an unfavorable environment for invasive yellow-flowered species. 
• Conduct a soil test and fertilize your lawn according to its needs. Ensuring the grass is healthy and robust can help it compete against weeds.
• Fertilization provides essential nutrients, promoting robust grass growth that outcompetes yellow-flowered weeds. 
• Biostimulants enhance soil health and promote robust plant growth, creating a competitive environment that naturally suppresses weed development.
• Thatch minimization and soil aeration enhance water and nutrient absorption, fortifying the lawn against yellow weed encroachment. 
• Proactive measures, such as pruning overhanging branches, contribute to a balanced ecosystem, discouraging the development of yellow-flowered weeds. 
• Mulching creates a protective barrier, suppressing weed growth by inhibiting sunlight penetration and creating unfavorable conditions for weed establishment.
• Pre-emergent herbicides form a protective barrier in the soil, preventing weed seeds from germinating and establishing. Examples include Prodiamine, which is applied in the fall, and Specticle FLO for warm-season lawns.

A holistic approach to lawn care is vital for effectively managing yellow-flowered weeds, ensuring a thriving environment for preferred grasses, and limiting resources available to invasive species as seasons change.

 

To keep your lawn healthy after weed treatment, check out our non-toxic biostimulants and fertilizers that make lawn care a breeze.