Indigo ProForce Onset 10GR Pre-Emergent Herbicide

Overview

Onset 10GR works by creating a weed-suppressing zone in the top 5 cm of soil, blocking weed seeds from germinating. Applied at the right time—before weeds germinate—it eliminates the weed problem before seedlings emerge, protecting your lawn without the need for post-emergent spraying.

Active Ingredients

Prodiamine 10 g/kg

Classification: Selective pre-emergent herbicide (Group 3). Prevents germination of grassy weed seeds in the soil.

Controls

Onset prevents germination of annual grassy weeds that invade lawns, particularly in summer and autumn when warm-season weeds thrive.

• Crabgrass (Digitaria spp.)
• Summer Grass (Paspalum spp.)
• Crowsfoot (Eleusine spp.)
• Parramatta Grass
• African Love Grass (Eragrostis curvula)
• Wintergrass (Poa annua)
• …and other annual grassy weeds

Application Rate

Area to Treat	Product Dose	Activation	Notes
100 m²	1–1.5 kg	Water in after spreading	For standard weed pressure
1,000 m²	10–15 kg	Water in within 24 hours	Up to 6 months weed suppression

How to Apply

1. Spread Onset evenly over the lawn using a broadcast or handheld spreader, aiming for uniform coverage without gaps.
2. Apply 4–6 weeks before weed germination typically occurs (March–April for autumn weeds; August–September for spring weeds). Timing varies by region and climate.
3. Weed control is most effective when activated by at least 6 mm of rainfall or irrigation, before weed seeds germinate and within 7 days after application.
4. Do not disturb the soil after application; avoid cultivation or heavy digging that would bring dormant weed seeds to the surface.
5. Residual control of up to 4 months at lower rates, or up to 6 months at higher rates.

Important Information

• Timing: Critical. Apply 4–6 weeks before weed germination begins. Too early and efficacy decreases; too late and weeds already germinate.
• Watering in: Activate with at least 6 mm of rainfall or irrigation, before weed seeds germinate and within 7 days of application. Do not irrigate to the point of runoff for at least 3 days after application.
• Rain: Do not apply if heavy rains or storms are forecast within 3 days.
• Mowing: The label states no mowing restriction.
• Over-seeding: Do not replant any crop or ornamentals, or over-seed with cool-season grasses for winter cover, for 6 months after application.
• Grass types: Safe on all established warm-season turf. Do not use on newly sown lawns or bentgrass.
• Silica granule (manufacturer claim): Per Indigo’s technical note, Onset 10GR is coated on a 200SGN (2 mm) dust-free silica granule containing 26% plant-available silicon. This is a manufacturer claim and does not form part of the approved label.
• No herbicide resistance: Pre-emergent herbicides work before weeds establish, eliminating the risk of resistance development.

Regulatory Information

APVMA Registration: 89917/133384

Withholding Period: Do not graze treated turf or lawn, or feed turf or lawn clippings from any treated area to poultry or livestock.

Re-entry Interval: The approved label states no re-entry period.

Safety Data Sheet & Label: Approved label (PDF) · Safety data sheet (PDF)

Get the Right Tools

For precise, even application, use a cordless battery spreader or push broadcast spreader. Browse our spreader options and other pre-emergent products.

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