Oxalis Control: How To Get Rid of Oxalis

Oxalis is an annual or perennial plant that some people find pleasant to look at because of their delicate clover-like leaves and attractive blooms. If you're trying to keep a uniform lawn, though, oxalis weeds can be one of the most annoying and difficult weeds to eradicate.

Oxalis is a perpetual weedy groundcover, which spreads via interlocking underground stems (or rhizomes) that are easy to separate. Oxalis has many seeds that drop when ready from little seed cases that look similar to okra. Anywhere the oxalis weed stem touches the ground, the plant can root with the potential of creating a large number of oxalis weeds.

This noxious weed usually dominates in areas of the garden planted with low ground covers. When oxalis grows alongside ground covers it is virtually impossible to get rid of without damaging the surrounding desired grass. Managing oxalis can be difficult because of its tough root system and the different methods the plant has to reproduce itself and persist.

If you are having a problem with Oxalis weed on your lawn, our DIY Oxalis treatment guide can help. The directions below were recommended by our lawn care experts and will show you how to properly get rid of Oxalis from your lawn or garden.

Identification

Before you can proceed with applying oxalis weed killers, you need to first be certain that the invasive plant you are dealing with is actually Oxalis. Misidentification of weeds can lead to using the wrong herbicide products, which can be a waste of time and money. Here are some defining characteristics of what oxalis looks like so you can easily identify it.

• Oxalis, also known as wood sorrel, looks very similar to another weed called clover, with the signature three-parted rounded leaves.
• Oxalis can grow between 6 to 12 inches tall and have unique shamrock-shaped leaflets in various color combinations including ones with speckles.
• Oxalis leaves arise from a creeping rootstock and unlike clover, oxalis bears flowers that vary in color from yellow to white or purple, depending on the species. At night, the leaflets fold back and droop.

Use the description and image above to help you to properly identify oxalis weed on your property. If you are not totally sure, contact us and send us a photo of your weed and we will assist you with oxalis weed identification as well as suggest treatment options.

Inspection

Once you have confirmed that you are dealing with oxalis weed, you can then move on to performing an inspection. During this phase, you will need to locate the areas where Oxalis is growing and observe the conditions of the area that may be helping Oxalis to thrive.

Where to Inspect

Oxalis thrives in partial shade and moist, poorly-drained soil but can spring up in almost any type of soil. Oxalis grows low to the ground and even after hand-pulling and mechanical control methods, it can return from just a small left behind stem fragment, fragile breakable rhizomes or bulbils.

What to Look For

You will be able to easily notice oxalis weeds on your property due to its shamrock-like leaves and if mature, it's bright flowers. It is often seen forming thick clusters of groundcover in open areas on lawns and flower beds.

Treatment

Before carrying out Oxalis control methods, please first make sure you have on the necessary personal protective equipment PPE (gloves, mask, glasses) prior to handling any herbicide chemicals.

If Oxalis is appearing on your lawn, apply msm turf herbicide. MSM Turf Herbicide is our go-to oxalis weed killer because of its affordability, ease of use and the fact that it is labeled for both warm- and cool-season grasses.

Apply msm turf herbicide in the late spring when the weeds are younger and smaller. Herbicides are less effective the older and more mature the weed gets. It may need to take multiple applications to get total control of this pesky weed, especially if you have a significant outbreak.

Step 1: Mix and Apply MSM Turf Herbicide

MSM Turf Herbicide can cover up to 1 acre of turf. Adding a surfactant to the msm turf herbicide mixture such as Nanotek Surfactant can enhance the effectiveness of the spray mixture. Apply Nanotek Surfactant per 1 gallon of solution. Apply 0.33 to 0.5 oz. of msm turf per acre.

Measure the square footage of your yard and then input the appropriate amount of msm turf herbicide in a pump sprayer or hose-end sprayer, then mixed with appropriate amount of water. Add surfactant to the msm turf herbicide mixture at a rate of 0.24 (1 gram) per gallon of the solution and agitate until well mixed.

Step 2: Apply the MSM Turf Herbicide To The Oxalis Weeds

Apply the msm turf herbicide solution to the oxalis on a fan tip nozzle spray setting to spray a fine mist that will evenly coat the weed. Noticeable results occur in 1 to 3 weeks.

Check back in 7 to 10 days to see the result of your initial application. In some cases, you may have to do a repeat application in 4 to 6 week intervals until the oxalis has completely died out.

Prevention

To prevent oxalis from popping up in lawns, make sure that you maintain thick, healthy turf. Here are some preventative measures we suggest taking to keep oxalis away.

• Fill up any bare spots in your lawn with sod or seed because that is where oxalis weeds will eventually spring up. Mulch garden beds with a two- to three-inch layer of organic mulch to prevent the weed from making a home amongst your perennials or vegetables. Without sunlight, the weed seeds cannot germinate.
• A pre-emergent (such as Nitrophos Barricade) may be a good preventative measure, especially if the problem is an annual occurrence. This product is not specifically labeled to treat Oxalis, but will eliminate weeds prior to germination. Oxalis thrives in open, fertile soil, which is why it can such a recurring problem where the soil is so favorable to growth.

Key Takeaways

What is Oxalis?

• Oxalis is a fast-growing and extremely aggressive annual weed known for its tendency to take over lawns and gardens with its low growing ground cover.

How To Get Rid of Oxalis

• Our top recommendation for killing oxalis is msm turf herbicide due to its ease of use, affordability, and effectiveness on both warm-season and cool-season grasses.
• Mix msm turf herbicide in a pump-sprayer and spot treat the areas of your lawn with the oxalis weed.

Preventing Oxalis Re-emergence

• A pre-emergent herbicide like barricade can be applied to your lawn before the growing season to prevent oxalis seeds from sprouting.