Why are my lime and lemon trees’ leaves splitting?

Question

The plants came from a well known nursery with good reviews. They are graphs and had no problems when I bought them in early March.

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Answer 1

It looks like your citrus has scale insects. This will completely destroy your citrus without treatment. First you will have to scrape off all of those white spots, as they is a hard protective shell for the insect. Once they attach, they do not move for the remainder of their lives.

After you have scraped as many off as you can, you will need to treat the tree with a broad spectrum miticide.

It will kill young scale, and it will kill eggs; it cannot penetrate the shell.

Spray this on the tree every 2 or 3 days, all over. Eventually, you will see them shrivel and die, what remains. Do this for 2 weeks, and you will start to see recovery and new growth after about a month.

https://www.gardeningknowhow.com/edible/fruits/citrus/controlling-citrus-scale.htm