How to Use a Vinegar & Water Solution on Plants
Vinegar is an excellent, safe solution for dealing with weeds in the yard and garden. It's not harmful to children or pets, and it's inexpensive enough to always have around. In addition to weed killing, vinegar can be a gardener's best friend because it helps kill slugs, can get rid of ants, neutralizes garden lime, cleans garden pots, and much more.
Vinegar is excellent for acid-loving plants like gardenias, azaleas and hydrangeas but it also kills weeds when used at full strength so you need to be careful how you use it on plants you want to keep alive.
Mix the vinegar and water together in a watering can, bucket or drip-system receptacle.
Apply the mixture to the soil around your plants to increase the acidity.
Take care to not get much--if any-of the mixture directly on the plant stems or leaves.
Kill weeds and grass. Apply full-strength vinegar directly to any weed or area of grass that you want to eliminate. Reapply to any new growth until the plant no longer comes back.