For preserving pumpkin, consider freezing, consider drying, but don't can.
For days I calculated the number of pint jars I would need to put up pumpkin. Never had I seen our pumpkin patch produce like this! Even after we had our fill of pumpkin blossoms (I love those things! Great little appetizers!), we still had dozens of pumpkins. Even after I gave away pumpkins to friends and relatives and then made pies, still I had a lot of pumpkins! So, with jars all gathered and lids enough to do them, pumpkins gathered, I just happened to read a blog I like to follow, and learned unexpectedly that the USDA does not recommend the canning of pumpkin puree, not even with a pressure canner. So, before I proceeded, I checked the Ball Blue Book guide to preserving. They have guidelines for drying and freezing, not canning.
Then I looked up the USDA guidelines for preserving pumpkin.
The USDA Extension Service in 1989 revised its canning recommendation for pumpkin, saying pumpkin puree is NOT a good candidate for canning since pumpkins have too much variation in thickness, acidity and water content to recommend a single process.
I decided to puree and freeze my pumpkin pulp in 16 oz. vacuum packs, just right for a pie or pumpkin roll. If you are interested in cooking cubed pumpkin,
the USDA says you can can that
but, cautiously, the current Ball Blue Book is not showing that method for home canning.