Growth through concrete

sussexbaker

Hiya

I've got a concrete slab surrounding my house, in one area plants have grown up through cracks in it. I've chopped them back but there's still a lot visible. What's my best option? I figured poison them (if so what sort) and then once they've died back fill in the cracks?

Thanks

Leif

Glyphosate is the best IMO as it will kill the roots. Just make sure there is not run off onto nearby plants you want. A neighbour had the cracks in her concrete drive filled, with cement I think. Certainly mixing up and applying cement or mortar is a very easy task, although you need to get advice from an expert, not me. You certainly would need to remove loose fragments, and it might be necessary to prime the concrete with something like PVA.

blossomhill_2

Can you identify the plants - any chance it is the dreaded Japanese Knotweed?

sussexbaker

It's not Japanese Knotweed thank god! I've got a feeling that it's a honeysuckle that's grown under the slab and the roots have come up. I will check with those who know more then me (ie Mother and Wife!) The runoff might be an issue though so will have to check on that too.

Thank you

Del_Astra

You could simply pour some salt down the cracks (again be careful not to drop it anywhere you don't want too), that will do it. Or take a knife and run that along the crack and pull as much out as you can, before you fill it in.

sussexbaker

How long will salt stick around for? I have visions of Roman's pillaging villages and salting the fields!

Yorkie1

Any weedkiller such as glyphosate will probably not work much at this time of year - the plant needs to be actively growing.

If you do use glyphosate in the late spring, bear in mind that it is designed to kill the entire plant - so if you want to retain the rest of the honeysuckle, glyphosate (or any other systemic herbicide) is not the way to go.

Leif

Another option is a flame gun. Or just pull up the growth. Repeated use will eventually kill the weeds, assuming there is not connected growth elsewhere e.g. roots from next door.

sammyroser

I have brambles growing through the concrete up one side of my house so know how you feel. I keep chopping it back but it keeps coming. Must remember one year to actually poison the dham thing and fill in the gaps.