High-density Planting and a Smaller Row Width Increased Yield and Decreased Fruit Size of Pumpkins

Pumpkins ( Cucurbita sp.) grown in North Carolina are a nascent specialty crop that has only risen to a national production level in the past 10 years. There are only general cultural management guidelines for this region, resulting in variation in plant density and inefficient production. Production field studies of the cultivar Kratos were conducted to investigate the impact of plant density and row width on marketable yield and individual fruit size for large carving pumpkins. Plant densities of 2691, 3588, 5382, and 10,764 plants per hectare with row widths of 1.5 and 3.0 m were grown in 2020 and 2021 in North Carolina. Data regarding fruit size, fruit size variance, and yield per area were collected. Fruit size in terms of weight, length, and diameter increased as plant density decreased. There was no difference in fruit size variation between plant densities and row widths. The fruit number per hectare and fruit weight per hectare increased as plant density increased, with the highest production at 10,764 plants per hectare. For years combined, reducing the row width from 3.0 to 1.5 m increased the fruit weight and diameter, but not the length. Additionally, the 1.5-m row width produced more fruit weight per hectare than the 3.0-m row width for both years. Growers can optimize fruit weight per area and fruit number per area by using a density of 10,764 plants per hectare. Overall, using a row width distance that is more equidistant to the in-row spacing promotes higher fruit yield and larger fruit size.