Apple cider vinegar is extremely versatile, including using it as a cleaning for your gardening tools, to keep animals and pests away from your plants, or as a fertilizer. Every gardener should keep some apple cider vinegar in their gardening supplies. 1. Kill Grass and Weeds​ When applying apple cider vinegar as a weed killer in your garden, avoid getting it on the plants you want to keep. 2. Keep away animals Placing a little apple cider vinegar around the edges of your garden is a great way to keep out household pets. 3. Clean Your Tools​ Clean rusty tools using apple cider vinegar. The slightly acidic nature of the apple cider vinegar naturally eats away at rust.