Does it have anything to do with the firestarter/ torch next to it?
Seriously though, we would need more info. Where are you located? This is being grown indoors? What is the light like - basil is a full sun plant. What does the soil feel like if you put your finger a couple inches down into it - compacted? loose? soggy? dry? Basil likes very loose, well drained, a bit sandy soil. What do the roots look like if you lift the plant out of the pot (really, you won't hurt it)? Firm and white? Dark and mushy? Are there roots circling around the outside of the rootball?