Calamondin tree

Question

This tree has developed a curling appeal on the leaves. What’s happening?

Answer 1

The most common reason for leaf curl in a citrus tree are pests and insects.
The cause could also be environmental or nutrition deficiencies.
Inspect the tree for signs of pests.
Neem Oil is a good treatment to use for most infestations.
Here are some links with more information.

https://www.gardeningknowhow.com/edible/fruits/calamondins/growing-calamondin-trees.htm
https://www.gardeningknowhow.com/edible/fruits/citrus/curling-citrus-leaves.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm