Hello, I have a newish bed that butts up against the back of my garage. It was previously a concrete walk. It gets adequate sun (~ 5 -6 hours) for the plants I try to grow. Usually by mid-July, everything starts to look limp. By August, I get small flying bugs (green or white) that seem to ruin everything. Is it the soil? The location? Any ideas? I'm in northern NJ, Zone 7. TIA