Well It seem that Sweet Georg,is better adapted to cool climates,and so0 it ripe better in the north east,here.
Tho they might look similar when grown in Fresno California,if grown here on east Coast the results will be different,in that one will ripe properly and one not,in the same Summer.
That is the results of adaptation.
One is adapted and one not,because the adapted one was grown possibly for hundreds of years ,in adverse condition,of cold Summer ,and it adapted to it ,by getting ripe in those conditions.