Overgrown.... help!

I have a small patch of garden, dimensions no more than 7 metres by 6 metres, that has become completely overgrown with this plant. I am not sure what it is, I would guess Knotweed of some sort. I have tried weed killer but it just grows back. I went away for a couple of months this year and when i returned I found it had covered the whole garden. I would be grateful for any suggestions

 

Looks like Bindweed to me.
Bit late now, but you could try Glyphosate,(round up).

 

Thanks. I did try spraying it with weedkiller containing glyphosphate but after a little bit of die back it all returns a few weeks later. I’m wondering if it is coming from deep underneath the soil and how I can get rid of it permanently?

 

It's well established, one application will not kill all the roots.
You need to have two or three goes at it when it is growing well, so best time is about June, with a follow up of any regrowth in a couple of months.
Really its too late this year now, you could try digging over the area and removing as much of the white roots as you can, then spray any growth next year.

 

Many thanks Pete

 

Persistence is the key unfortunately. Weed killer will help, as will cutting it back. But the main issue is the mass of rhizomes. You really need to dig them out and dispose of properly (could leave them to dry and them burn it) even leaving some will result in the weed growing back. Don't be tempted to put it on the compost heap etc. Good luck - with some hard work you will get rid of it.

 

Yes, effective chemical weedkilling will not work at this time of year.

I have eradicated bindweed by digging out thoroughly......once the ground is apparently cleared sieve through it again checking for every piece of white bindweed root. You will find long strands of it so gently pull it as you loosen the soil.
In spring spray as soon as you see new growth using glyphosate. Spray any regrowth during the summer as you see it. By late summer all bindweed should be gone.
You could still plant there in late spring....annuals would be good....but carefully spray the weed between the plants.

I dont think bindweed is difficult to eradicate. It is susceptible to glyphosate