How to get iron into my meyer lemon?

How to get iron into my meyer lemon?

I've had a meyer lemon for about three years. I've noticed it looking a little yellow in some of the leaves lately, so I figure it's feeling a bit anemic. I haven't been able to find any iron or fertilizer specifically for citrus yet. Is there something around my house that can get some iron into the soil until I find a garden store with the right stuff?
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garden photos

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Just a little cutie to share…

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A kitchen garden – at last!

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advice on coverlets

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