Leaves curling UP. Any ideas why?

I'm a relocated Californian and I miss my citrus trees SO much! I finally decided to order these 2 dwarf trees and pot them. They arrived 2 weeks ago and are in the full sun on my patio now and seem to be surviving the move. They came with bare roots, so I bought cactus, palm and citrus potting soil since I read they need good drainage. The soil is Miracle Grow for cactus, palms and citrus.

I did put a few pebbles at the bottom around the large hole in the middle of the barrel to prevent the soil from escaping. I figured the pebbles wouldn't take up too much space since the trees are fairly small (3 years old) and the barrel has plenty of soil for them. They had this one hole (about the size of a quarter) for drainage for 2 weeks. I drilled 4 more holes in the bottoms of the barrels today since I'm concerned they might not be draining enough and it's causing the leaves to curl.

I'm very concerned about the curling leaves. They are still green and aren't falling off (yet) but seem to curl upward more and more each day. What causes this?

Also, what/where should I get fertilizer for them? Should I fertilize now that it's August? I read that we should not fertilize after August 1st.

Any comments or suggestions would be very welcome. I'm used to living in what used to be orange and lemon groves in Southern California. We just stick citrus trees in the ground and water once a week there and the fruit is delicious! This is quite different in Tennessee!

This post was edited by Heidittttttt on Sat, Aug 24, 13 at 22:53