Bow & Arrow
Selective broadleaf weed killer. Controls White Clover, Bindii, Cat's Ear, Capeweed, Plantain, Cudweed and Creeping Oxalis.
See what size bottle you need
Herbicide & Pre-emergent Calculators
Work out exactly how much selective weed killer you need for your lawn area. These calculators cover both post-emergent herbicides (kill existing weeds) and pre-emergent herbicides (stop weeds before they sprout). Pick a product below, enter your lawn area, and the calculator does the rest.
Estate
Selective broadleaf weed killer for lawns. Controls Clover, Bindii, Cat's Ear, Capeweed, Plantain and more.
See how much Estate you'll need
Dicamba M
Broadleaf weed control for all turf. Targets Clovers, Bindii, Dandelion, Plantain, Thistles, Wireweed and more.
See how much Dicamba M you'll need
Tempra
Selective post-emergent for Mullumbimby Couch and Nutgrass in established lawns. Granular pack.
See how much Tempra you'll need
Coliseum
Selective grass weed control. Targets Winter Grass (Poa annua) and Ryegrass in established lawns.
See how much Coliseum you'll need
Monument
Broad-spectrum selective herbicide. Controls Bindii, Ryegrass, Winter Grass, Nutgrass, Oxalis, Kikuyu and more.
See how much Monument you'll need
Propyzamide
Pre-emergent for Winter Grass and Ryegrass in Couch and Buffalo lawns. Rate depends on your grass type.
See how much Propyzamide you'll need
Odessa
Granular selective herbicide. Controls Bindii, Oxalis, White Clover, Ryegrass, Winter Grass, Bahia and Onion Weed.
See how much Odessa you'll need
Barricade
Pre-emergent herbicide. Stops Summer Grass, Crab Grass, Crowsfoot, Winter Grass and Paspalum before they germinate.
See how much Barricade you'll need
Spartan
Pre-emergent herbicide (prodiamine). Long-lasting control of Summer Grass, Crab Grass, Crowsfoot, Winter Grass and Paspalum.
See how much Spartan you'll need
Glyphosate 360
Non-selective broad-spectrum knockdown herbicide. Kills weeds, grass and unwanted plants for spot-spraying, garden bed prep, paths and driveways. Rate varies by weed maturity.
See how much Glyphosate you'll need
Herbicide Calculator FAQ
What's the difference between pre-emergent and post-emergent herbicides?
Pre-emergent herbicides (Barricade, Spartan, Propyzamide) stop weed seeds from germinating — apply before weeds appear. Post-emergent herbicides (Bow & Arrow, Estate, Dicamba M, Monument, Odessa, Coliseum, Tempra) kill existing weeds in your lawn.
When is the best time to apply weed killer?
Apply post-emergent herbicides when weeds are actively growing — spring and autumn are ideal. Avoid spraying when temperatures are above 28°C or when rain is imminent. Pre-emergents should go down before weed seeds germinate (late summer for winter grass, late winter for summer grass).
Will these herbicides damage my lawn?
All of these are selective herbicides — designed to kill weeds without damaging your turf grass. Always check the label for compatibility with your specific grass type. Some products have restrictions (e.g. Propyzamide is for Couch and Buffalo only).
How long until I see results?
Most post-emergent herbicides show visible effects within 7–14 days, with full kill in 3–4 weeks. Pre-emergents work invisibly — you'll know they're working because weeds don't appear.
Do I need a spreader sticker or wetter?
Most liquid post-emergent herbicides benefit from a wetting agent (like Pulse Penetrant or BS1000). It helps the spray stick to waxy leaves and improves uptake. Check each label for specific advice.
Measure your lawn
Enter your address, then trace your lawn on the satellite map.
Enter your address above to load the satellite map.
Measured area:
0 m²
Click 'Start drawing', then click each corner of your lawn on the map. Click the orange first point (or the button) to close the shape. Drag any point to adjust.