Help suspected couch grass!

[seeyouinanotherlifewhenwearebothcats]

So last summer we planted up a rockery. Plants doing well all seemed good. Except the grass growing through it was insane! The man at the garden centre advised getting bark down or I’d be weeding practically daily. But now the bark is down and I can clear the bed of all grass and literally a few days later, it’s back. It’s soul destroying and it is growing up round all the plants. Saw a lady with a similar issue on here last night and read up on couch grass. DH and I have tried to pull it all by hand again tonight but will a weed killer get rid long term? And how do I protect the plants? Can’t seem to find a spot stick type applicator anywhere. When I get a single blade of it it has a very long thin root but tufts have several rhizomes so I’m nearly sure it’s what it is. Advice much appreciated!

Could be couch. Quite a few other grasses have a creeping rootstock too. Grasses are very sensitive to glyphosate. Try a fine paintbrush?

Oooh a paintbrush is a great idea! So brush on the glyphosate and it just dies? Do I still need to dig it out?

May need repeated weekly to be sure.

It takes up to 3 weeks to take effect because it has to be absorbed into the plant and then works by disrupting growth process. So absolutely no point in repeating weekly. Grass is particularly susceptible to glyphosate, so while other plants may need a repeated application several weeks later, grass is less likely to.

Ok here’s hoping 💪

I posted about grass in borders recently, so the thread you're referring to might be mine. The grass in your photos looks like what's growing in my borders too, though it's hard to tell.

I've whacked some weed membrane over the top and will leave it for a while and then investigate and see what's going on underneath. If it's died off then I might keep the membrane and put bark/mulch over the top. If it's still going then I think I might have to get the weedkiller out!

I find it's not that bad if you mulch it and keep on top of weeding it. The best thing is planting thickly ... so it has no room to spread!

@hamustro could have been! Ooh please update me with how the membrane is doing. Could be worth a try also. It’s just such a nuisance!

@BarrelOfOtters yeah I am hoping a lot of the plants in the bed will fill out and eventually provide more cover. I’ve a hellianthemum that appears to have valiantly doubled in size so it’s doing it’s bit 😂

There are plants like Yellow rattle that are parasitic to grass so reduce their growth if you like the look of them, normally used to control grasses in wildflower meadow.

My experience is that yellow rattle seedlings don’t like being overshadowed in their early stages. They also need a reasonable amount of grass, so you’d be in a perpetual loop - grass dies down, yellow rattle dies, remaining grass multiplies, you need to reintroduce yellow rattle.