What's wrong with this marigold?

[juul-buzze]

Leaves of this one plant are wiliting. They're indoors on a windowsill facing south. I thought maybe they were getting scorched by the sun but the other plants in the same pot are doing fine. I did add a general fertilizer for blooming plants a couple of weeks ago.

 

[Marck]

Greetings, welcome to the Forums.

The leaves of the Marigold (Tagetes erecta cv.) in the OP photograph may have been scorched bt the sun, It can happen erratically. Continue to observe the situation. If this is an isolated occurance, there is no need to do anything except pinch off the dead leaves.