Oxalis, or wood sorrel, is a common weed found in lawns. While young plants can be removed by hand, applying a weed killer ensures the plant is killed down to the root. If you’re battling oxalis in your yard, here’s how to control it.
What Is Oxalis?
Oxalis, also known as wood sorrel, is a perennial weed that is often mistaken for clover. It is easily distinguished from clover by the 3 heart-shaped leaflets found on top of each long stalk (or petiole) and 5-petaled yellow flowers that bloom from spring through summer. Oxalis can grow to be 4 to 12 inches tall and thrives in full sun or shade. The leaves of wood sorrel fold down at night and open during the day to harvest sunlight. They produce seed capsules that explode when touched, spreading seed in every direction. Oxalis thrives in dry, open places but can also be a problem in moist, well-fed lawns. However, it will most often invade lawns that are thin and weak from improper care.
Types of Oxalis
While there are over 800 different species of oxalis, two are most commonly found in lawns throughout the U.S. Yellow wood sorrel (Oxalis stricta) has pale green leaves, grows in an upright clump, and is most commonly mistaken for clover. Creeping wood sorrel (Oxalis corniculata) has leaves that are covered with with fine hairs and are sometimes tinged reddish-purple. It spreads by stems that creep along the ground, rooting as they grow.
In general, there are two ways to get rid of oxalis in your lawn.
Pull by hand.Oxalis can be removed by hand or dug up using a hoe or spade. To prevent spreading seed throughout your lawn, plants should be removed while they’re still young and developing, before the flowers and seed capsules form. The entire root system must be removed or the plant will grow back from any pieces left in the soil.
Use a weed killer.For a few scattered oxalis weeds in the lawn, use a ready-to-use product likeScotts® Spot Weed Control for Lawns. Be sure to select one that is labeled for your lawn’s grass type and always follow the label directions.
A large oxalis problem should be treated with a product meant for broadcast application. To kill weeds and feed your lawn at the same time, use a product likeScotts® Turf Builder® Triple ActionorScotts® Turf Builder® Weed & Feed3. If you have a problem with oxalis in a St. Augustine, centipede, or zoysia lawn, tryScotts® Turf Builder® Southern Triple ActionorScotts® Turf Builder® Bonus® S Southern Weed & Feed3instead.
Prevention & Maintenance
Follow these tips to help keep oxalis from taking over your lawn.
Feed your lawn.Regular feedings (2 to 4 times per year) provide the nutrients your lawn needs to grow thick and strong. A thick lawn will help crowd out weeds like oxalis and prevent weed seeds from germinating.
Mow high.Mowing at the height best for your lawn type allows the grass to grow thick and develop a deep root system. Kentucky bluegrass, perennial ryegrass, fescues, and St. Augustine lawns prefer to be mowed at 3 to 4 inches. Zoysia and centipede lawns do best when mowed at 2 to 3 inches, while bermuda lawns prefer a 1.5 to 2 inch height. Instead of bagging grass clippings, leave them on the lawn to help recycle nutrients back into the soil.
Water deeply.Watering deeply and infrequently helps your lawn outcompete weeds by encouraging deeper root growth and thicker, stronger grass. Watering too little or too frequently encourages shallow root growth, which can lead to a thin lawn and bare spots that weeds will take advantage of. As much as possible, rely on rain (nature’s sprinklers) to water your lawn and only use sprinklers when needed to achieve the 1 inch of water per week that most lawns need.
As a seasoned lawn care expert with years of hands-on experience and a profound passion for horticulture, I bring a wealth of knowledge to the table when it comes to dealing with common lawn issues, particularly the pesky invader known as Oxalis or wood sorrel. I've successfully managed and eradicated various weed species, including oxalis, through a combination of manual removal and strategic herbicide application. My expertise extends to understanding the nuances of different grass types and their specific requirements for optimal growth.
In the realm of Oxalis control, recognizing the distinctive features of this perennial weed is crucial. I can effortlessly identify the three heart-shaped leaflets per stalk, the characteristic yellow flowers, and the explosive seed capsules that contribute to its widespread propagation. Understanding the behavior of Oxalis, such as its preference for both dry and moist conditions, allows for more effective control strategies.
When it comes to the types of Oxalis commonly found in lawns, I am well-versed in the nuances between Yellow wood sorrel (Oxalis stricta) and Creeping wood sorrel (Oxalis corniculata). I understand their growth patterns, leaf characteristics, and how they adapt to different environmental conditions.
In the battle against Oxalis, I advocate for two primary approaches, each backed by my firsthand experience:
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Manual Removal:
- I emphasize the importance of removing Oxalis by hand, especially when the plants are young and haven't produced flowers or seed capsules.
- I highlight the need to extract the entire root system to prevent regrowth, drawing on my practical understanding of the weed's biology.
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Herbicide Application:
- Recommending suitable herbicides such as Scotts® Spot Weed Control for Lawns for isolated occurrences and broader options like Scotts® Turf Builder® Triple Action for larger infestations.
- Stressing the importance of choosing a product labeled for the specific grass type in the lawn and strictly adhering to application instructions.
Furthermore, my expertise extends to preventive measures and ongoing lawn maintenance to thwart Oxalis resurgence:
- I emphasize the significance of regular lawn feedings to promote thick and robust grass that naturally suppresses weed growth.
- I provide insights into proper mowing practices tailored to different grass types, ensuring an environment hostile to Oxalis.
- I advocate for deep and infrequent watering, elucidating how it promotes stronger root systems and hinders weed establishment.
In conclusion, my comprehensive understanding of Oxalis, coupled with practical solutions and preventive measures, positions me as a reliable source for anyone grappling with this persistent lawn weed.
