Pumpkins are those globular orange squashes that smile back at us from windows and porches on Halloween. They are actually fruits native to Central America. Pumkins were widely cultivated by Native Americans and eventually shared with English settlers in the first years of European settlement. Since then, they've replaced the turnip as jack-o-lanterns as well as provided generations of pies, soups, breads and casseroles. You'll find pumkin in plain old squash dishes and contributing to roasted pumpkin seeds. They are members of the genus cucurbitacae and a pumpkin's reproduction habits are the same as relatives like winter squash, gourds, melons and cucumbers.
Pumpkins pick their spaces carefully. Since they're warm weather crops, they grow best in open spaces where they get at least six hours a sun a day and where soil is fertile and friable so they never sit in water. They prefer a soil with a pH that ranges from 5.5 to 6.5. Once established, pumpkins can re-seed themselves yearly, providing they are an "open germination" or heirloom variety. Hybrids tend to either reproduce differently than the parent or not at all. Like all fruits, pumpkins flower in spring, then set fruit with seeds that mature with the fruit. Once the growing season ends, from 100 to 140 days after germination, the fruit and plant shrivel with first cold blasts of winter and the mature seeds are exposed as the pumpkin is eaten by animals or slowly decomposes in place. Each seed contains an embryonic plant with all the genetic information it needs to become a full-grown copy of its parent.
Along with genetic information, each seed contains nutrients to get it through the winter and early spring. A hormone, absciscic acid (ABA), controls the seed's germination to provide a period of dormancy before the tender dicot breaks the surface of the soil. Other chemicals and enzymes prepare the embryo and soften the shell so that it can begin growing when the soil is reliably warm and there is a sufficient supply of water and sunlight to support the little plant. Once conditions are right, the little plant begins growing and after maturity begins to bloom. The first blooms of the pumpkin are all male, providing pollen for bees that will return to pollinate the second set of blooms which will be female. When this happens, the cycle is complete. Fruit follows blooms with the next year's embryonic plants growing inside.