I did a lot of searching, and couldn't find any references that suggested the seedlings need chilling... ? As I mentioned, I found one entry that said that blooming plants slow down their flower production once it gets very hot, but may resume if cooler nights come along, but this didn't seem to refer to seedlings. Given that osteospermum are commonly grown, one would think such a recommendation (i.e. chilling the seedlings) would not be obscure, if it was quite important?
