One of my apple trees has the same. Mine does have mildew on some of the new growth. I suspect it's down to the weather - very cold, then very dry, then very wet and now very dry and hot - it's been quite a lot for plants to adjust to. I think all you can do is ensure the tree is not short of water and let it grow out. Mine usually recovers after a few weeks, but the affected leaves usually drop, then it sometimes gets wooly aphids......
Billericay - Essex
Knowledge is knowing that a tomato is a fruit. Wisdom is not putting it in a fruit salad.
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Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
Mine does have mildew on some of the new growth.
I suspect it's down to the weather - very cold, then very dry, then very wet and now very dry and hot - it's been quite a lot for plants to adjust to.
I think all you can do is ensure the tree is not short of water and let it grow out.
Mine usually recovers after a few weeks, but the affected leaves usually drop, then it sometimes gets wooly aphids......
Billericay - Essex
Knowledge is knowing that a tomato is a fruit.
Wisdom is not putting it in a fruit salad.