Much like the trend of snacking peppers – those bite-sized bells that consumers adore – the next big thing in butternut squash is actually smaller. There’s one cultivar leading the way, but researchers at Iowa State University recently tested four others to see how they stack up.

Anne Carey, a graduate student, and Ajay Nair, associate professor, both in the Department of Horticulture at ISU noted that in recent years vegetable breeders have developed butternut cultivars that are smaller than standard squashes weighing one to 2.5 kg. The most popular mini, dubbed “Honeynut,” is a cross between butternut and buttercup squash.

In a poster presentation at Great Lakes Expo, the team reported that Honeynut is said to produce sweeter, more flavorful fruits with thin skins while maintaining that classic butternut shape. With the success of Honeynut, breeders are working to develop new mini cultivars to meet consumer demand. The mini-butternuts weigh 0.25 – 0.7 kg and grow under the same conditions as full-size butternut.

Carey and Nair said that while mini-butternuts are gaining market value, there is a lack of information on their yield, quality and post-harvest longevity. The objective of their study was to evaluate five cultivars on their yield, sweetness and storability in Upper Midwest growing conditions.

The five organic cultivars evaluated were the previously mentioned Honeynut as well as “Brulee,” “Butterscotch,” “Butterbaby” and “Tiana.” They were all seeded on June 3, 2021 and then transplanted into certified organic land at the ISU Horticulture Research Station on June 21. The squash was harvested on Sept. 24, and fruits were categorized as either marketable (with number, weight and length measurements taken) or unmarketable (due to insect damage, being unripe, rotting or deformed shape).

Post-harvest, the squash was cured for seven days and then placed in a storage cooler. Cubes were cut from the fruits and the juice squeezed from them was analyzed for total soluble solute content (aka Brix, for sweetness) every five weeks up to Week 20.

What they found through this trialing is that Honeynut was the only cultivar to have more marketable fruit than unmarketable, although Tiana came close. Below them were the performances of Butterbaby and Butterscotch, with Brulee doing the worst.

However, Tiana was both longer and heavier than the other cultivars, appearing more like a traditional butternut. The other four cultivars were much more in line with the mini description.

Other notable results: Honeynut produced more marketable fruit per plant (3.7) than the other cultivars. Butterscotch produced the smallest yield of marketable squash per plant (1.7) but did not suffer from a significant amount of insect damage or rot. Brulee appeared to be the most susceptible to black rot.

Carey and Nair concluded that all five evaluated cultivars are suited for production in the region – although Tiana is definitely not a mini. Brix among cultivars increased from harvest until Week 15, indicating decent mini-butternut storage potential for about three months.

They added that future research should evaluate additional quality metrics of squash fruits in storage, such as flesh firmness and incidence of rot.

by Courtney Llewellyn