I bought this established magnolia in April and planted it in the garden. Did well until about May/June when we had a slightly hotter few days. Although the plant likes sun. It was well watered in evenings so was not a watering issue. Leaves turned brown and in some cases black. But some very healthy . New leaves were like this on opening. The company I purchased it from were not sure but said it could be verticillium wilt but really were not sure-unlikely but didn’t really know.
I have moved the plant to a cooler spot, it’s in a pot and it picked up. Still getting the same issue but less severe. Any ideas?