What Happened To Our Pumpkins?

Asked July 18, 2018, 9:03 AM EDT

Last year we grew Baby Pam Pumpkins. After harvesting and while processing we decided to save some seeds for use this year. We planted in the spring and nearly all seed produced plants but, the fruit on those plants are quite different from the pumpkins. Some are yellow and some are green. What happened to our pumpkins? Thanks, Chuck & Karen de la Durantaye

Mason County Michigan

3 Responses

Hi Chuck & Karen,

Anytime you are saving your own seeds you can't really predict what kind of plants the seeds will produce. The seeds you planted are, genetically, half Baby Pam, and half whatever pollen was dropped off by the bee that pollinated the plant. This pollen could be from Baby Pam or another type of pumpkin. Based on my research on Baby Pam, it doesn't look like it's a hybrid, so the pumpkins should be somewhat true to type.

The plants look healthy. Baby Pam has 99 days to maturity, so I wouldn't expect any pumpkin fruit to be mature/orange yet (assuming you didn't plant in early April). The fruit in your first picture looks like a healthy young pumpkin, which are green and with yellow/light colored striping. It will turn orange with time. The other two will likely turn a darker green and eventually orange, and the bumps may or may not go away.

Let me know if you have any other questions, or if things don't turn around in a month or two.

Hi Marissa,
Thanks for the input. The conclusion we have come to is that they did indeed cross-pollinate. Last season we had pumpkin, zucchini and yellow squash all in close proximity. From the seeds we saved and planted we have three types of fruit appearing on the vines now, bright yellow (and squash shaped), dark green (as the color of zucchini) and now emerging are fruits that look like the pumpkins we expected to see. We also have distinctly different different plants. The plants with yellow and green fruit are more compact and less vine-like (as with squash) and the pumpkin fruits are on long vines.

Hello again,

Good observations. Many of the crosses you suggest are possible as they are the same species as pumpkins (Cucurbita pepo). Things can cross pollinate within a species, but the results of the cross will only be noticed when seeds are saved. For more information, see this write-up from Iowa State.