Defeat Common Florida Lawn Weeds: A Comprehensive Manual

Combating common Florida lawn weeds requires understanding and action, as our environment plays a pivotal role in their proliferation.

This comprehensive manual will explore effective strategies for identifying and eradicating Florida weeds, emphasizing the necessity of both individual and government roles in fostering a healthier environment. By delving into the specifics of crabgrass, dollarweed, doveweed, and Florida betony, we aim to equip you with the knowledge needed to maintain a lush, weed-free lawn.

Crabgrass

Crabgrass, a formidable opponent in the battle for a pristine lawn, particularly thrives in Florida's warm climate, especially in Saint Augustine grass. Its resilience is showcased by its ability to produce over 200,000 seeds during a summer season, making it crucial to address this weed before it overtakes your lawn. Unfortunately, the options for post-emergent herbicides are limited, as most can harm Saint Augustine grass along with the crabgrass. This weed's thick, carpet-like growth pattern not only suffocates other plants but also leaves bare spots of dirt upon its death, further complicating lawn weed control efforts in Florida.

To effectively combat crabgrass, understanding its lifecycle and growth conditions is key. It is an annual summer weed that germinates when soil temperatures rise above 60 degrees Fahrenheit in early spring and completes its life cycle by fall. It finds its stronghold in thin, bare areas of the lawn, particularly those suffering from disease or pest issues. Therefore, maintaining a thick, healthy turf is paramount. This not only minimizes spaces where crabgrass can grow but also blocks the sunlight necessary for weed seed germination, making it one of the most effective Florida weed control strategies.

Here are practical steps to prevent crabgrass infestation:

• Mow your lawn to the proper height: Avoid cutting it too short.
• Stick to a fertilizing schedule: This encourages healthy turf growth.
• Fill in bare spots: Use grass seed or sod to cover exposed soil.
• Consider professional lawn aeration: This improves turf health and resilience against weeds.

Dollarweed

Dollarweed, known for its round leaves with scalloped edges and small star-shaped white flowers, is a challenge many Florida homeowners face. Thriving in wet conditions, it's often found in areas with poor drainage or excessive irrigation. To tackle this persistent weed, consider the following strategies:

Cultural Practices for Prevention:

• Mow at the right height for St. Augustine grass (3.5-4 inches) to promote a thick turf that can outcompete dollarweed.
• Fertilize 2-4 times a year with a slow-release product to support healthy turf growth.
• Ensure adequate sunlight (6-8 hours/day) and water only when necessary to discourage dollarweed growth.

Effective Removal Techniques:

• Hand-pulling can be effective but ensure removal of all white rhizomes to prevent regrowth.
• For chemical control, herbicides containing MSMA, glyphosate, or imazapyr are recommended. Always follow manufacturer instructions for safety.

Long-term Management:

• Adjust soil pH and nutrient levels as needed to create conditions unfavorable for dollarweed.
• Consider hiring a professional lawn care service for assessment and treatment.
• Use pre-emergent herbicides to prevent seed germination and post-emergent herbicides for actively growing plants. Products like MSM Turf Herbicide (Manor) or Fahrenheit are recommended, with Avenue South being particularly effective for St. Augustine grass.

Doveweed

Doveweed, a warm-season annual that finds its niche in Florida's wet landscapes, poses a unique challenge for lawn weed control. Thriving in areas ranging from landscape beds to poorly drained soils, its ability to form dense mats by rooting at the nodes makes it a formidable opponent. Key to its management is understanding its lifecycle; seeds germinate with the advent of warm, wet weather around April or May, leading to rapid growth. The weed is identifiable by its shiny shoots, narrow leaves with parallel venation, and small blue or purple flowers emerging from midsummer to fall.

Preventive Measures:

• Correct Irrigation: Avoid overwatering and correct drainage issues to deter doveweed growth.
• Mulching: Apply 1 to 3 inches of mulch in landscape beds to prevent seed germination.
• Preemergence Herbicides: Utilize products like flumioxazin (Broadstar®) or indaziflam (Marengo® G) for effective pre emergent control.

Control Strategies:

• Hand-pulling: Effective but ensure complete removal of stem fragments to prevent regrowth.
• Herbicide Application: For preemergence control, consider pendimethalin + dimethenamid-P (FreeHand®). Post-emergence, Celsius herbicide is recommended, potentially requiring multiple applications.
• Turf Management: Combine herbicide use with turf management practices for comprehensive control, planning for a 2-3 year management strategy due to seed survival.

Florida Betony

Florida Betony, often referred to as Rattlesnake weed, is a persistent invader in Florida lawns and landscapes. Characterized by its square stems, opposite lance-shaped leaves with toothed edges, and distinctive white, segmented tubers that resemble a rattlesnake's rattle, this aggressive perennial weed remains green throughout winter, becoming most noticeable from late summer to early fall and again in late winter to early spring.

Effective Control Strategies for Florida Betony

Herbicide Application:

• For Bermuda and Zoysiagrass: Use broadleaf herbicides like 2, 4-D + MCPP + dicamba (e.g., Timec, Weed-B-Gon).
• For Centipede and St. Augustinegrass: Atrazine-based herbicides (e.g., Ortho Weed-B-Gon Spot Weed Killer for St. Augustine Lawns) are effective.
• Apply herbicides in fall to emerged plants, with a follow-up in mid-winter or early spring.

Physical Removal:

• In landscape beds or around trees and shrubs, digging out the weed completely is most effective. Ensure all roots and tubers are removed to prevent spreading.
• Mulch and landscape fabrics are generally ineffective against this weed.

Maintaining a thick, healthy lawn through proper mowing, fertilizing, and insect/disease control is crucial for preventing Florida Betony. For landscape beds, thorough removal of roots and tubers is recommended, with disposed materials not being composted to avoid spreading. You’ll need to be as consistent as you can be with application; controlling Florida Betony may take several years with repeated applications necessary in heavily infested areas.

Conclusion

Tackling common Florida lawn weeds demands a blend of strategic action and knowledge, as highlighted through the control measures for crabgrass, dollarweed, doveweed, and Florida Betony. These strategies underscore the importance of understanding each weed's life cycle, optimal prevention methods, and when to apply specific treatments. 

The journey to a weed-free lawn is not just about eradication but also about embracing preventive practices and seeking professional assistance when needed. In addition to integrated pest management, Orange Pest Control offers lawn care services to help you keep your Florida lawn beautiful year-round. Contact us today for a free quote!