I sprouted a little orange tree from a seed and planted it a large
styrofoam coffee cup with "supersoil" potting mix.
It has grown with 3 or 4 shoots, the longest is about 9 inches but
doesn't do well in direct sunshine.

It seems content in my kitchen window with indirect sunshine, but if I
take it outside in direct sunshine, 1 or 2 of the shoots will turn
brown and die in a couple days.

I'm wondering if it needs some special fertilizer, or more water, or a
larger pot, or less sunshine?

What are the recommended conditions for small orange trees?

-Bill