So I've been saving green wine bottles for quite some time now in hopes of making path/planting borders in my new herb garden this spring. Now that construction time is nearly upon me it occurred that I should ask if anyone has done something like this, and if they've had a problem with the bottles freezing and breaking in the winter. I live on the edge of zones 6/7 (mostly 7) and it does get down to single digits here sometimes, but usually not for long. My plan was to dig a trench and upend the (capped) bottles so that about 4 inches stick up above the ground, then tamp soil around them. I'd just hate to go to all the effort only to have them burst like bombs come next winter. Any thoughts or advice would be greatly appreciated