Glyphosate, how it works and what it will kill
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The most important thing to know about glyphosate before you pick the bottle up is that it isn't selective, so it kills whatever green plant it lands on. It doesn't know the difference between the couch grass coming up through your pavers and the lawn right beside it, and that one fact decides everywhere you can use it and everywhere you can't.
How it works, and why it looks like nothing's happening
It goes in through green leaf rather than through the soil, and once it's inside the plant it moves down into the roots, so the whole thing dies instead of just burning off at the top. That's why it works on the stuff that keeps coming back from a root or a runner, and it's also why it's slow. You'll see very little for the first few days, and a plant will usually take 1 to 2 weeks to go properly.
So leave it alone while you're waiting. Pulling it or mowing it partway through just stops the chemical getting down to the roots, and then you're back where you started with a weed that looks dead for a fortnight and comes back anyway.
Where it earns its place
Driveways, paths, fence lines and the gaps in paving are where it's genuinely the right tool, because there's nothing there you want to keep alive. Clearing a bed before you plant it works too, as long as you give it the time the label asks for before anything goes in the ground.
Where it'll cost you
Over the top of a lawn it will kill the lawn. If the problem is broadleaf weeds in grass then you want a selective lawn weed and feed instead, which is a completely different product doing a completely different job.
Anywhere near something you're keeping, the thing that gets people is drift, so a still day matters more than most people think. A light breeze will carry a fine mist a lot further than you'd guess, and you won't know it's happened until something you liked starts going yellow a week later.
The safety bit, and it's short
The label is the legal instruction and it's genuinely worth reading, because the rate changes depending on what you're killing and more is not better.
Cover up while you're spraying, so long sleeves and gloves and something over your eyes. Keep the kids and the dog off it until it's dried, and wash your hands before you touch anything else. Don't spray near a waterway or over a tank inlet, and don't spray flowering weeds while the bees are working them, because there's no reason to take the forage off them when tomorrow will do just as well.
Rain will wash it off before it's done anything, so if there's a shower coming in the next few hours, leave it for another day.
One last thing about mixing
Mix what you're going to use and no more, because a made up batch sitting in a sprayer in the shed is a problem waiting to happen. The bottle also tells you which containers it doesn't get along with, so it's worth a read before you mix it up in whatever's nearest.
Shop related products
- Brunnings Glyphosate 360 Weed Killer Concentrate 1L. The one this post is about, for paths and fence lines.
- Brunnings Feed n Weed Extra Strength Concentrate 1L. The selective one, for broadleaf weeds in a lawn you want to keep.
- Easy Wetta Garden Mulch 50L. Mulch is what stops the weeds coming back once you've cleared a bed.
- Brunnings Garden Compost with Seaweed 25L. For rebuilding a bed after you've cleared it.
Did you know we also stock P2 dust masks and gardening gloves in the shop, which are the two things people most often go without when they're spraying. They're not on the website, so give us a ring on (08) 8536 4333 to check what's on the shelf.
The rest of the range is in our garden centre, and the garden range is online if you want a look first.
Read next
- Lawn weed and feed, how to use it and when not to
- Brunnings Bug and Fungus Kill, and where not to use it
- Brunnings Kikuyu Lawn Seed, what it is and when to sow it
I'm fussy about which way the wind's going before I spray anything, and I'd much rather be called fussy than have to explain a yellow stripe across somebody's lawn.
Cheers,
Candeece
