It might just be that they dried up in the hot weather. If so they'll uncurl now it's rained.
You might also want to check for ants breeding black fly on the underside. They suck the moisture from the leaves causing them to curl over. You can usually just scrape them off with a wet finger.
It might just be that they dried up in the hot weather. If so they'll uncurl now it's rained.
You might also want to check for ants breeding black fly on the underside. They suck the moisture from the leaves causing them to curl over. You can usually just scrape them off with a wet finger.