Q.Mulberry tree.
The young leaves that have just come out on my mulberry tree are curling up? What is causing that?

Certified GKH Gardening Expert
This problem isn't the easiest to correct, as you must first find the cause. There are a few things that will cause this, typically.
When the tree gets hot, it can do this in an attempt to "breathe" better. This case is hard to correct, but these hardy trees.
This can also occur when the tree gets too wet, as an attempt to "breathe" more as a means of removing moisture faster.
Last, it can be common with mulberries in full sun. They are, actually partial shade tolerant, and enjoy a few hours of shade during the middle of the day.
Here is an article to give you more information on growing these trees: https://www.gardeningknowhow.com/ornamental/trees/fruitless-mulberry/how-to-grow-mulberry-trees.htm