Kostas

The folding of the leafs is a mechanism to reduce evaporation and transiration from the leafs so as to keep the water needs of the leaf in levels that can be satisfied from the roots and not let the leaf dry out/burn. It also reduces the leaf surface exposed to direct sun during the high heat conditions and thus helping with sunburn too although it doesnt totally prevent it in non acclimated leas.
Its also this way i like banana leafs the most!

__________________
''To try,is to risk failure......To not try,is to guarantee it''