Oxalis weed (also commonly known as wood sorrel) is a fast-spreading garden weed that can be difficult to control once established. The most effective way to get rid of oxalis is to remove it early, target the root system, and use a combination of hand removal and selective herbicide treatments where appropriate. Left untreated, it spreads quickly through bulbs and seeds, making control more difficult over time.
Most problematic Oxalis weeds have a fleshy tuber beneath the soil, allowing them to store energy and making them quite resistant to efforts to kill them. Others produce multiple tiny bulbils which ‘explode’ when disturbed, each producing a new plant. It is also easy to bring them into the garden in the pots of other plants.
Quick answer: How do you get rid of oxalis?
To get rid of oxalis (wood sorrel), dig out the plant including bulbs and roots, avoid disturbing soil unnecessarily, and apply a selective herbicide for lawns or a non-selective treatment for garden beds. Repeat treatments are often needed because oxalis can regrow from small bulb fragments.
The following species of Oxalis weed are problematic across gardens in Australia:
- Oxalis articulata (Pink sorrel, pink wood sorrel, sour grass)
- Oxalis bowiei (Bowie’s wood-sorrel, red-flower sorrel, cape shamrock)
- Oxalis corniculata (Creeping oxalis, creeping wood sorrel, procumbent yellow sorrel, sleeping beauty)
- Oxalis corymbosa (Pink oxalis)
- Oxalis exilis (Least yellow sorrel)
- Oxalis incarnata (Pale wood-sorrel, crimson wood sorrel, climbing Oxalis)
- Oxalis latifolia (Fishtail wood-sorrel, broadleaf wood sorrel, pink shamrock)
- Oxalis pes-caprae (African wood sorrel, Bermuda buttercup, Bermuda sorrel, buttercup oxalis, Cape sorrel, Cape cowslip, English weed, goat’s foot, Oxalis cernua, sourgrass, Soursob)
- Oxalis purpurea (Large-flower woodsorrel)
Oxalis plants are often found in gaps between the sides of raised beds, between paving stones, and other hard-to-reach cracks!
What is oxalis?
Oxalis is a large group of weeds (commonly called wood sorrel in some regions), and not all spread the same way. The main lawn species, creeping oxalis (Oxalis corniculata), spreads by seed and creeping stems from a taproot rather than bulbs. Bulb-forming types, such as soursob (O. pes-caprae) and fishtail oxalis (O. latifolia), are more common in garden beds. It produces clover-like leaves and small yellow or pink flowers, and is commonly found in lawns, garden beds, and pots. Because it spreads aggressively, it is often referred to as oxalis weed in gardening contexts.
Oxalis plant facts
- Common names: Oxalis, wood sorrel, oxalis weed
- Plant type: Perennial weed (creeping oxalis spreads by seed and stem; soursob and fishtail oxalis spread by bulb)
- Spread method: Varies by species – creeping oxalis by seed and creeping stems; soursob and fishtail oxalis by bulbs and bulbils
- Leaves: Clover-like, often in groups of three
- Flowers: Yellow, pink, or white depending on species
- Key issue: Regrows easily from bulb fragments
- Where it grows: Lawns, garden beds, pots, and disturbed soil
How do you identify Oxalis weed (wood sorrel)?
Oxalis spp. is sometimes confused with clover, but can be distinguished by having heart-shaped leaves and five flower petals. Its flowers are delicate and attractive, and are white, pink, violet, red or yellow:
- Oxalis articulata. Pink or violet flowers with petals 1-1.5cm in length. Grows to 45cm tall and prefers moist conditions.
- Oxalis bowiei. Bright pink flowers, the stem is typically 30cm or more in height.
- Oxalis corniculata. Small yellow flowers, with green or reddish-purple leaves which closely resemble clover. This low growing, creeping weed can easily be missed around the base of other plants. Very common and a rapacious spreader.
- Oxalis corymbosa. Pink flowers and dark green leaves.
- Oxalis exilis. A tiny species with intricate yellow flowers. Native to Australia.
- Oxalis incarnata. Individual stems up to 30cm each, but can spread higher against a wall or fence. Does particularly well in moist, shaded sites. White or light pink petals.
- Oxalis latifolia. Very low growing, with no stem. Fishtail or heart-shaped leaflets with pink, occasionally white, flowers.
- Oxalis pes-caprae. Bright yellow flowers on this densely growing upright plant, which can reach up to 40cm in height. Particularly invasive, each plant can typically produce 20 new plants from its bulbils.
- Oxalis purpurea. Dark green leaves, single deep pink flowers, occasionally white, with petals that are 2cm or more in length.
Most Oxalis species are not native to Australia, which thankfully means the seeds of them are rarely viable. However, they often have a milky coloured or brown bulb with many bulbils attached, which can help them to spread and are hard to reach when under a lawn.
What are the signs of Oxalis weed (wood sorrel)?
Oxalis spp. can furtively colonise an area of lawn, quietly creeping beneath the runners of grass to establish itself. It is then difficult to eradicate without damaging the grass at the same time. The first sign of it may be the innocent looking, beautiful flowers, popping up in the lawn. On closer inspection of the soil surface, it becomes apparent that grass has been peppered by this invasive weed.
Most troublesome species of Oxalis have tuberous and fleshy roots, which will sit below the grass surface and spread through the soil, making it even harder to bring under control.
How to get rid of Oxalis weed (step-by-step)
Oxalis is a persistent weed that spreads through bulbs and seeds, so effective control usually requires a combination of physical removal, prevention, and (where necessary) targeted herbicide use.
Step 1: Remove early growth before flowering
Start by tackling oxalis before it flowers and sets seed. Mow or rake affected areas to remove top growth and collect all plant fragments. This helps disrupt the plant’s energy production and may slow its spread over time, although it will not fully remove established bulbs.
Step 2: Remove by hand (best for small infestations)
For small patches, carefully dig out entire plants by hand. Use a trowel to lift surrounding soil and ensure all bulbs and bulbils are removed, as even small fragments can regrow. Never add Oxalis to the compost heap, as it may spread further.
Step 3: Use mulch or physical suppression in garden beds
In garden beds, reduce regrowth by hoeing lightly and then applying a thick layer of mulch, such as Scotts Flower & Garden Bed Mulch or garden compost, to block light and suppress new growth.
Step 4: Use a selective lawn weedkiller
For larger infestations in lawns, where the methods above aren't effective, we recommend a selective herbicide such as Scotts Lawn Builder Bindii Weedkiller Refillable Bottle - particularly for creeping oxalis (Oxalis corniculata).This Oxalis weed killer can be used all year round whenever weeds are actively growing, and on all lawn types, including buffalo, although always check the label to ensure it is suitable for your lawn.
Step 5: Treat difficult infestations carefully
An alternative is Roundup or another glyphosate-based weed killer, for spot-spraying in garden beds. However these can kill other nearby plants if not handled carefully, so they're not recommended for use on lawns or near other plants.
Step 6: Repeat applications as needed
Expect to apply chemical treatments several times. Follow the manufacturer’s guidance so that weedkiller is applied at a rate which is safe for the lawn and other plants and animals.
Step 7: Support recovery with lawn care
Between applications of weedkiller, and in close parallel with the manufacturer’s instructions, applying a Scotts Lawn Builder™ lawn food can give grass a boost and help it to get ahead of the Oxalis.
How to control oxalis on hard surfaces
In the cracks of hard surfaces, burning the tops off with a garden flame gun will weaken the plant. Never use a flame gun on total fire ban days or in dry conditions.
Last resort: lawn replacement
If infestations are severe and widespread, the most effective long-term solution may be to remove the affected turf completely, eliminate all weed material, and establish a new lawn.
How do you prevent Oxalis weed (wood sorrel)?
As with most opportunistic weeds, prevention is better than the cure. Keep the lawn in good health by feeding the lawn with a suitable fertiliser, such as Scotts Lawn Builder™ All Lawn Types Lawn Food, applied using Scotts® Easy Handheld Fertiliser Spreader. Always check that a product is suitable for the type of lawn growing in your backyard, as some are not suitable for varieties of grass.
Avoid disturbing the soil, which can spread bulbils and other sections of plant, and check newly purchased plants for weedy growth on the surface of the soil.
FAQs
What kills oxalis weed naturally?
The most effective natural method is hand removal with full bulb extraction, although repeated efforts are often required to prevent regrowth.
Why is oxalis so hard to kill?
Oxalis spreads through underground bulbs and seeds, meaning it can regrow even if only part of the plant is removed.
How do you stop oxalis from spreading?
Prevent spread by removing plants early, avoiding soil disturbance, and maintaining a thick, healthy lawn or garden cover.
Is oxalis the same as wood sorrel?
Yes, oxalis is commonly known as wood sorrel, though the name varies by region.
