Wrinkling Leaves

i saw some threads about this the otherday but i cant seem to find them now
but on my plants fan leaves there starting to wrinkle like at the viens of the plant so its not smooth its like wavy does anyone know what this is caused by

could it be caused by heat?

Post a pic !!!!! Or cant help

potassium deficiency that is caused by ph lockout if it looks like this: View attachment 1825377

Credit to: http://www.420magazine.com/forums/problems-pests-disease-control/81275-cannabis-plant-pest-problem-solver-pictorial.html

yes i know it is from another site but we are here to help grow the green. not get in turf wars.
hope this helps

Comed is right, the only other thing i know that does this, is some types of virus/fungus,

if its in flowering, potassion deficiency happens, a lot.
in vegetative, its not that common, seeing as how they dont require as much potassium.
either way, use a well balanced nutrient, at a weak dosage 1/2 strength... and make sure it has n-p-K (k is for potassium/potash). throw in some micro nutrients. and use a fungus killer for good measure, 1/2 strength again, pour some in the soil, and spray some on the leaves too.


EDIT: check pH! that could be the cause too.