Here's what I use:
Exactly.. White vinegar (1 gallon), table salt (1 cup) and a squirt of dishwashing soap mixed together and placed in a sprayer and sprayed onto the weeds, or any plants you want to die.
Take vinegar, add a bit of dish liquid to it and then spray. . Do not use on a lawn, only on a driveway or sidewalk area.
This article has 115 inspirational & DIY ideas for a rustic wedding. It's been pinned several thousand times. Hope this helps and blessings to the happy couple. Hugs, Holly