Is this a disease? It's only for the one plant. 4 other plants are okay.. so far. I hope it's not a disease or a bug. I have no experience in growing anything and this is my first time. I am also in arizona so it'll be interesting how things work out. Please help me figure out the problem, thanks in advance.
Looks like sunburn. Did you get water on the leaf while it was in the hot sun?
