Tomato plants' leaves curling. How much sunlight needed?
Apparently I have 2 problems with my tomato plants this year. First of all, I have 1 Fourth of July, and 4 of another, hybrid type I cant remember the name of. I planted them in a new spot this year, and in the new spot I chose, I assumed I'd get at least 8 hours of direct sunlight, but what I have noticed is that since I planted them in a 20 foot long row with 2 peppers mixed in, the plants at one end of the row get probably 1.5 to 2 hours less sunlight than the ones at the other end due to the tall trees at that end. I knew there would be some difference, but I didnt think it would be nearly 2 hours.
Aside from that, none of these tomatoes and pepper plants are getting more than about 5 hours. That means they are now getting between 4.5 to 6.5 hours of direct sun per day, and when the sun starts dropping lower in the sky, I am sure the current amount they are getting will be reduced, so that by September they will be at or under 4 to 5 hours.
The 4th of July is producing tomatoes, and the others have produced a couple so far, and should start producing about now, but the plants themselves are not very thick, in fact they are quite thin. That brings me to problem #2.
With 1 of the hybrid tomato plants, I noticed it started showing curled leaves from just 3 weeks after they were planted in late May. They began as very small plants about 8" tall in a small 6-pack type market pack with openings about 1.5" x 2" wide at the top.
Its leaves continued curling as it grew, with more curled leaves coming out. But it grew slower than the other 5. But just about 2 weeks ago I noticed 2 other plants of this same variety starting to show curling leaves as well. I planted 2 of these same plants in a different area about 20 feet away, but they show no curled leaves. They have been watered about 2-3 times per week and I added mulch over the bases about 2 weeks ago to help hold water.
What is causing the curling leaves, and how much sun is not quite enough?