Does Adding Vinegar to Soil Help Water Absorb Better?

Changing Soil pH

• Since vinegar is acidic, it can lower the pH level of soil, or make the soil more acidic. This will benefit plants like azaleas and blueberries that need more acidic soils. However, because vinegar is soluble in water, it does not stay in the soil like granulated soil acidifiers, so its pH-lowering qualities are short-lived. Watering with a mixture of vinegar and water once per week can benefit acid-loving plants, but more than that can harm plant roots. If a gardener knows that he has hard water with a lot of salts, adding 2 tbsp. of vinegar to 1 qt. of water will neutralize these salts and benefit plants.

Fertilizer Additive

• Apple cider vinegar is another common ingredient in organic fertilizer mixes because the sugars in the vinegar feed beneficial microorganisms. One organic liquid fertilizer recipe called Garrett Juice includes 1 tbsp. apple cider vinegar, 2 cups compost tea, 1 tbsp. liquid seaweed and 1 tbsp. blackstrap molasses mixed with 1 gallon of water.

Natural Weed Killer

• Acetic acid burns plants and has therefore been used as an herbicide and weed killer. Pour undiluted white vinegar in the highest concentration available into a spray bottle and spray on weeds. The vinegar will kill the top part of the plants, but perennial weeds will grow back from the roots. The herbicidal properties of vinegar mean that it should never be used full strength for any other garden purpose such as increasing soil acidity or killing harmful microorganisms.

Natural Fungicide

• Vinegar -- especially apple cider vinegar -- has been used as a natural fungicide for hundreds of years. To make a fungicidal spray, mix 3 tbsp.of apple cider vinegar with 1 gallon of distilled water. Spray on plants to control fungal infections like black rot and other plant diseases. Some organic gardening experts also recommend pouring white vinegar onto ant mounds to kill and repel ants in the garden, though vinegar is not a proven insecticide.

Cleaning Outdoors

• White distilled vinegar can be used as a cleaning product all over the house to kill mildew, remove mineral buildup and disinfect surfaces, and it can be used the same way to clean outdoors as well. A 50/50 solution of vinegar and water will clean glass surfaces, and straight white vinegar can be used to remove lime scale on pots and vases and mildew on outdoor surfaces. Full-strength vinegar can also be used to clean rust off of garden tools.