BigBill said:Oil, drops of dish soap and water would have done fine. Most people use vinegar to spray and kill weeds!
BigBill said:What's done is done. The air getting to it may be more beneficial then covering with.
You have to remember that vinegar is acetic acid. Acids and plants are not generally a good idea! Citric acid, hey a slice if fresh orange in my whiskey sour is fine as a garnish.