Lava Wall

[nani1970]

I have some lava stone walkways that have grass and weeds growing between them.
Should i just use Round Up, or is there another recommendation?

[macuu222]

Yes...kill the growth first. If you pull it out while still green and growing it will loosen the the wall stability and slowly start falling apart.

[Digitalis]

Round Up is dangerous and not just to plants. Use boiling water or a homemade herbicide of pickling vinegar, salt and a dash of dish soap. For a long term solution, remove the walkway!