What Effects Does Lemon Juice Have on Plant Growth?

Lemon juice has the same damaging effect as acid rain splashing over green growth. Yet, as harmful as this citrusy liquid can be to healthy plants, gardeners hail it as a weed killer that is ecologically friendly, effective and inexpensive. Depending on its use, lemon juice can be friend or foe to foliage.

lemon and juicer
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Understanding Acid Rain

Acid rain is created through natural sources, such as decaying matter and volcanoes, as well as man-made pursuits that emit sulfur dioxide and nitrogen oxides. In the United States, a significant amount of these harmful emissions is attributed to fossil-fuel burning activities such as electrical power generation. This chemical reaction occurs in the atmosphere, and the aftermath is acid rain. Any rainwater with a pH reading that is less than a 7 is considered to be acid rain and detrimental to fish and plant growth. Lemon juice has a pH level of 2.2, so pouring this liquid over plants is mimicking the negative effects of polluted rainfall.

Simple Experiment

Take three similar potted plants. Place all of these plants in a healthy environment. For example, find a sunny spot if this type of plant require lots of sunshine, or line all three pots in a shady corner if no sun is recommended for that species. Water the first plant with only distilled water. Pour vinegar on the second pot and lemon juice on the third. Be certain to dampen the leaves and saturate the soil of each of the three potted plants. The foliage nourished with only water will be healthier than the other two plants. The plants that have been treated with vinegar and lemon juice will show signs of acidic damage.

Weed Treatment

Gardeners recommend lemon juice as an organic weed treatment. A mixture of four ounces of lemon juice and one quart of cider or white vinegar will zap the wild growth by lowering their pH levels enough to kill them. This organic concoction is most effective during the hottest hours of the day. The impact of spraying this homemade blend on pesky weeds will last only a few minutes, so you may need several applications to do the trick. Avoid spritzing nearby plants that you do not want to destroy.