[dmz3]

I live in Manassas, VA and I started growing hops in my yard and weeds are spreading throughout the lawn.  What commonly available pre emergent and post emergant herbicides (i.e. from Lowes, Home Depot, etc) can be used on a lawn near hops vines without harming the hops vines? Is weed and feed harmful if used near hops?

[Kevin]

Are you trying to keep grass out of your hop beds or prevent hops from popping up in your yard? Use mulch to keep grass and weeds out of your hop bed... use a barrier type border to keep the hops in. The very reason I got rid of my hops is that they are a very aggressive plant and the rhizome root system spreads like wildfire. Even after digging up the main rhizome and giving them to a friend I still had hops shooting up in my lawn for several years.

[Robert]

If I understand correctly, the concern is killing lawn weeds without harming hops.  I would think that a product like Preen, which is basically a hormone treatment to prevent weed seeds from germinating, would be safe to use, but it is only useful at the start of the season.  Once you have active vegetation you're trying to kill, I'd be very wary, because, as Kevin notes, the hop's root system is broad and deep.  I'd worry about a general, broadcast spreading or spraying of anything that kills broad-leaf plants, as it could soak down and reach the hop roots.  Maybe you could try one of those sprays you carefully apply to individual weeds and that are absorbed through the leaves (Weed-B-Gone and Spectracide I think come in targeted spray bottles) or go full OCD and root them out one by one with a hand tool.  If you have dug down and cut back the spread of the hop crowns, and maybe installed a barrier as Kevin suggests, you might have a better idea where the "safe zone" is where you don't have to worry about affecting your hops.  Read labels to get some idea of how the product gets into the plant's system.

[majorvices]

Just put cardboard down around the hops after you pull up the weeds you don't want.