What is going on with my lemongrass?

Question

I went out to look at my lemongrass and water plants to find a ton of it with these white rain drop shaped spots surrounded by black. see photo for details. what is it and how do I fix it?

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Answer 1

This is a type of rust that, typically, effects Bluegrass. This will be best controlled with dolomitic lime, and wettable sulfur, or instead you can use copper fungicides. I tend to lean towards the first option due to less toxicity, but the second option is stronger.

Although this is not the same rust species, it is very similar in how it spreads, and how it is controlled, so this article will help: https://www.gardeningknowhow.com/edible/herbs/lemongrass/brown-leaves-on-lemongrass.htm