Bindii (Bindi Weed) in Australian Lawns: ID & Control

What Is Bindi Weed?

Bindii (Soliva sessilis), also known as bindi weed, Jo-Jo, or Onehunga, is a low-growing winter annual broadleaf weed in the daisy family. It is best known for its sharp, spiny seeds that embed in bare feet, puncture skin, and cause irritant contact dermatitis.

It germinates in autumn when soil moisture is adequate and temperatures drop. By the time you notice it in spring, it has already established a dense rosette and is approaching its seeding window. Once the burrs have formed, chemical control becomes unreliable. Any spray applied at that stage kills the plant but leaves the spines in the ground to cause problems through summer.

After reading this, you will be able to:

• Identify bindii and tell it apart from similar-looking winter weeds
• Know exactly when to spray for maximum effect
• Choose the right bindi herbicide for your turf type

Why Bindi Weed Is a Problem

• Spiny burrs. Each plant produces 5 to100 seeds with rigid spines that pierce skin and paws. Once a burr drops to the soil surface it stays there even after the plant dies.
• Rapid spread. Bindii forms a dense low-growing carpet that smothers desirable turf, especially in bare or thin areas.
• Prolific seeding. It can flower and set seed repeatedly through the season, building the soil seedbank fast.
• Skin reactions. Bindii causes bindii dermatitis and an irritant contact dermatitis from spine contact. It is a genuine health risk for barefoot use of lawns.
• Hard to control late. Once the spines form, killing the plant doesn’t remove the hazard. Timing is everything.
• Indicator of compact soil. Bindii thrives in thin turf over compact, low-fertility soil. This is also poor ground for desirable turf species to recover quickly.

How to Identify Bindi Weed

For a full photo ID guide to Australian turf weeds, see the Weed ID Chart.

Bindii is frequently confused with carrot weed (Cotula australis) and swinecress because all three produce parsley-like, divided leaves and grow as low rosettes over winter.

The easiest field separation:

• Carrot weed produces pale yellow flowers on stalks in early winter. Bindii flowers later and has no flower stalks.
• Swinecress has a strong skunk-like smell when crushed. Bindii does not.
• Bindii alone produces spiny burrs.

Key identification features

• Leaves: Low rosette, parsley-shaped, deeply divided, bright green. Spread to 150 mm across.
• Flowers: Small, bright yellow, no stalks, appear at ground level.
• Burrs: Spiny, produced from late spring. Each spine is rigid and pointed.
• Height: Up to 50 mm.
• Photosynthetic pathway: C3, Grows in the cool season, dies back in summer heat.
• Reproduction: Seed only. No vegetative spread.

Differences Between Bindii and Similar Winter Weeds

Habitat

Bindii favours compact, stressed, or worn turf and bare soil. It is a reliable indicator weed of compaction and low turf vigour. Check our weed ID chart for photographic confirmation.

Lifecycle and Timing

Understanding the lifecycle is the most important factor in control. Bindii is only reliably killable during a specific window.

The rule: Spray in June to July when rosettes are actively growing and before the plant reaches 50 mm across. Everything after that is damage limitation.

Cultural Control of Bindii

Cultural control reduces the seedbank over time and makes chemical programs more effective.

• Hand pull before seeding. Effective if done before any burrs form. Pull the entire root system — leaving root fragments does not cause regrowth (unlike perennial weeds) but disturbs soil and can create germination sites.
• Aerate compacted areas. Bindii favours compact soil. Core aeration improves turf vigour and makes the environment less favourable for this weed. See our soil compaction calculator.
• Maintain nitrogen fertility. Healthy, actively growing turf outcompetes bindii. Apply the correct N rate for your grass species and season — thin, underfed turf is where bindii establishes.
• Fill bare patches. Every bare patch is a bindii germination site. Overseed or turf any gaps as soon as they appear in late summer.
• Mowing: Not effective as bindii’s prostrate growth habit keeps it below mower height.

Pre-emergent Herbicides for Bindii

Pre-emergents applied in late summer to early autumn (February–April) before soil temperatures drop to 13 to 16°C at night can prevent bindii germination. This is the most cost-effective program for sites with heavy annual infestations.

Effective actives (registered in Australian turf):

Note: Oxadiazon (Echelon) gives poor control of bindii and should not be selected for this target.

Timing: Apply when nights cool to 13 to 16°C, typically March to April in southern Australia. Late application is better than none as even a partially-timed application reduces seedling numbers.

Post-emergent Bindi Herbicides

The ideal post-emergent window is June to August as rosettes are small and actively growing, no burrs have formed, and systemic herbicides move well through the plant.

Key principles:
– Treat the entire affected area rather than spot-spraying. Bindii spreads from seed, so untreated patches refeed the seedbank.
– Plants are dead 7 to 10 days after spraying under good conditions.
– Once burrs are visible, control is still possible but the spines will remain in the lawn regardless.
– In cool weather, use higher label rates and allow extra time for visible symptoms.
– Always add a non-ionic surfactant (NIS) or appropriate adjuvant to this improves contact with the small rosette leaves.

Selective Post-emergent Herbicide Table

Buffalo grass owners: Duke 100WG and Warhead Trio are your two safe selective post-emergent options for bindii. Casper, Recondo, Contra M, and Dicamba will damage buffalo.

Which product to choose?

For most lawn situations, Casper (prosulfuron + dicamba) is the strongest selective option where buffalo is absent. Apply in June to July with NIS, allow 4 to 6 weeks for full control, and follow up with a spot spray in August if any regrowth appears.

For buffalo lawns, Duke 100WG is the most reliable registered option. Apply with NIS and allow 3 to 4 weeks for visual symptoms to appear.

Non-selective Control

For total renovation, hardscape edges, or areas where turf is being removed:

Written by Jerry Spencer, Principal Agronomist, Gilba Solutions Pty Ltd. BSc Hons Soil Science, former STRI agronomist, author of Nutrition of Sports Turf in Australia (CSIRO/Landlinks Press). 35+ years advising golf courses, stadiums and councils across Australia, NZ, UK and Europe.

Related pages: Weed ID Chart | Carrot Weed | Warhead Trio Herbicide | Broadleaf Weed Control in Autumn | Pre-emergent Herbicide Guide | Herbicide Resistance Chart