Leaf Curling - I never knew!

I received an email from our garden president with information about leaf curling in the garden. Evidently some other members were concerned about this since another member had sprayed some weed killer around. As it turns out there was no other evidence of the weed killer but we had had some severe weather changes. We had some nice warm 70s-80s weather then a cold snap of 40s followed by 90s. So those big weather changes caused the leaf curling. Who knew? I guess I am so simplistic - it is green, growing, no holes from bugs - I am good. But I took pictures anyway to show for future reference....