Pumpkin “chukking” and physics demonstrations apart, pumpkins (Cucurbita pepo) typically don’t explode unless they’re carelessly dropped from great heights. They do tend to split with some force under certain conditions because of their growth habits. Heavier “giant” pumpkins (Cucurbita maxima) are far more sensitive to moisture, temperature and managing than others.

Splits and Splats

Several ethnic conditions set the stage for splits in pumpkin skins. Pumpkins are warm-weather fruits, growing rapidly on annual vines as they approach maturity. So long as soil moisture, potassium, calcium as well as other fruit-forming enzymes are plentiful, a massive pumpkin can put on pounds of weight every day. Since the fruit reaches maturity, its skin hardens but growth persists. Extra nitrogen fertilizer, particularly ammonia-based nitrogen fertilizer applied during maturity can add to increase, creating an internal pressure capitalized upon by college students and pumpkin festival organizers alike.

When Pumpkins Explode

A 2008 narrative on National Public Radio told the story of a Massachusetts farmer, Steve Connolly, who grew giant pumpkins. Connolly lost four pumpkins, weighing over 1,000 pounds each, to spontaneous explosions starting as fissures as weak spots in the epidermis. According to Connolly, his giant pumpkins put on 40 to 50 lbs every day. Giant pumpkins may be more prone to explosion because of greater sulfur and water, aggressive pruning, cushioning and overall pampering — Connolly wraps his giants in blankets at night — that keep them growing but also place substantial stress on their skin.

See related