It definately sounds like something has been nibbling its leaves. Exactly what insect is difficult to say as there are many that it could be, including slugs, caterpillars, etc. I would recommend treating the plant with neem oil, which is a safe and effective insecticide. Here is more information: https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm
Answered on June 15, 2015
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