I have two plants (in the same bed, next to each other) with leaf problems.

The pieris has older leaves wwhich are dull green and heavily mottles with yellow. New leaves are bright green and healthy looking. The hosta leaves have patches that are brown and burnt-looking.

This bed is just a few years old, fairly heavy clay soil, which I amended initially, but not in the past couple of years. I'm wondering of this is a soil deficiency, like iron or magnesium. Or something else...? There are other plants in this bed (hosta varieties) which look healthy.

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