120 days. If you want to break the giant pumpkin World record then this is the variety for you! Atlantic Giant produced the 2006 World Record pumpkin that weighed in at 1502lbs! 50 and 100lb pumpkins are normal, and if the plants are limited to one fruit per vine, then 200 to 300lb pumpkins are not uncommon. The key to growing a massive pumpkin is rich fertile soil, bright sunshine, lots of water and Atlantic Giant seeds!