Avocado plant and the problems with their leaves

Question

Why do the leaves of an avocado plant turn brown or look like there is rust on them?

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Answer 1

Is this in container? This looks like a severe magnesium deficiency... Dolomitic lime will correct this. This article will help: https://www.gardeningknowhow.com/edible/fruits/avocado/avocado-tree-growing.htm