Behind the Forecast: How weather affects pumpkin crops

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How weather affects pumpkin crops (10/4)

LOUISVILLE, Ky. (WAVE) - It's officially Fall, so that means it is pumpkin season! Around 80 percent of the United State's pumpkin supply is available in October.

The weather plays a big part in how and how much crops grow; however, pumpkins can be more weather-sensitive than other plants.

Plants do need water to survive, but too much rain can delay planting and cause plants to rot. Mildew damages plant leaves and stems; it can even kill pumpkin vines and fruits.

Dry weather, like droughts, can lead to smaller and lighter pumpkins.

Pumpkin patch at Huber's Orchard and Winery in Borden, Indiana.
Pumpkin patch at Huber's Orchard and Winery in Borden, Indiana. (Source: Gary Pyles /WAVE 3 News)

What about temperatures? Well, chilly spring weather can keep pumpkin blossoms from maturing. Since bees don't fly until temperatures reach at least 55°, they are not pollinating the flowers. Once temperatures fall from the fifties into the thirties, pumpkins plants will slow down, stunt, then stop growing and producing fruit.

Pumpkins seeds don't germinate in the cold ground while seedlings can be injured by frost, according to the University of Illinois Extension. Pumpkins are planted as early as late May in northern states through early July in southern locations. Soil temperatures should be at least 65° for pumpkin planting according to the University of Minnesota Extension. The University of Illinois Extension says that pumpkins planted too early in the year can rot before Halloween.

An early freeze can kill pumpkins.

Hot and dry weather can cause pumpkins to produce too many male blossoms and not enough female blossoms, which can lead to a smaller harvest. Pumpkins can tolerate short bouts of hot weather well, according to the University of Illinois Extension.


The sun, while vital to a pumpkin's growth, can damage a pumpkin plant. Leaves may wilt in temperatures warmer than the mid-80s.

This year's weather was quite beneficial for Huber's Orchard and Winery in Borden, Indiana. The wet spring helped the pumpkin crop grow considerably. During the on-going drought, a spokesperson said they have been diligent in keeping the pumpkins watered throughout their growing cycle. Their farmers focus on keeping vines and leaves up which provides shade for the pumpkins and prevents sunburn. This summer's dry weather has resulted in "very hardy pumpkins." Huber's said that the pumpkins are sturdier and will laster longer than they typically would after being picked.

Just heads up for those planning to carve pumpkins: in ideal conditions, cool and dry, an uncarved pumpkin can last several weeks to a month. Heat and plenty of moisture speed up the decaying process, according to Huber’s Orchard and Winery.

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