The Purpose of the Study
There has been an explosion of interest in backyard production of fresh vegetables. As many gardeners face smaller growing spaces, growing squash (summer or winter) pose a challenge because of their larger plant size and potentially limited fruit yield. This study examined four types of winter squash (acorn, spaghetti, butternut, and delicata), totaling 13 different varieties, that were marketed as “space saving” or a “bush-type habit”. The study will be repeated in 2025.
Materials & Methods
Thirteen winter squash varieties noted as having a smaller footprint were selected for this study. Four squash types used: acorn, butternut, spaghetti, and delicata. Seeds were planted into hilled ground beds on June 7, 2024, with two seeds per planting hole. After germination, plants were thinned to one seedling per hill. Plants were spaced on four-foot centers with four plants per replication; varieties were randomized between rows. Irrigation was provided via furrow irrigation. During the growing season, weed control was maintained through hand-pulling, hoeing, and the use of ground cloth. Squash were fertilized twice using slow-release fertilizer; the first application was when the plants formed four true leaves, and the second when the plants began setting fruit.
Plant growth measurements were taken on August 31, 2024. The height and width of plants were recorded to assess compactness; observations of disease and insect presence were also noted. Harvesting took place on October 4, 2024, following a period of cool weather with light frost. At harvest, fruit from each plant was counted, weighed, and measured to determine the average number of fruits per plant, as well as the average size and weight of individual fruits. Taste testing was conducted on October 23, 2024, with 17 participants. The squash was oven-roasted without seasoning, and participants evaluated the squash based on flavor, texture, color, tenderness, smell, and overall appeal. The squash types were judged within their respective categories (i.e. acorn squash was compared only to other acorn squash varieties).
Fast Facts:
- Winter squash are not always feasible to grow because of their potentially large plant size and yields.
- There were 13 winter squash varieties in the research trial.
- Winter squash were evaluated for overall size, flavor, and yield.
Results & Comments
The summer of 2024 was one of the hottest and driest in Colorado Front Range history. Insect pressure included grasshoppers and squash beetles, though neither caused significant damage to the squash plants. The primary disease observed was powdery mildew, which appeared late in the season and had minimal impact on plant health and yield. The squash varieties that produced the greatest number of fruits per type included Goldilocks (acorn), Butter Baby (butternut), Angel Hair (spaghetti), and Bush Delicata. Within each squash type, there were both compact and vining varieties. For example, in the acorn squash category, Goldilocks was a compact variety, whereas Early Acorn displayed a vining growth habit. In the taste test, Bush Delicata and Honey Bear (acorn) were ranked as having the best overall flavor. Among all squash varieties, butternut squash was rated highest for overall flavor, excluding the delicata type.
| Squash Type | Variety | Number Fruits/ Plant* | Fruit Weight (lbs) | Plant Width (in)** | Plant Habitat | Overall Flavor (1-5)*** |
| Acorn | Honey Bear | 2.5 | 1.0 | 28.0 | Bush | 4.2 |
| Goldilocks | 4.2 | 1.2 | 37.9 | Bush | 2.0 |
| Reno | 2.3 | 1.5 | 37.3 | Bush | 2.9 |
| Early Acorn | 3.9 | 1.5 | 69.7 | Vining | 3.9 |
| Bush Table Queen | 2.7 | 1.1 | 31.4 | Bush | 3.0 |
| Butternut | Honeynut | 4.3 | 0.8 | 38.6 | Vining | 3.9 |
| Butter Baby | 5.1 | 1.1 | 32 | Vining | 3.2 |
| Butter Bush | 1.9 | 1.5 | 34.8 | Semi-bush | 3.3 |
| Spaghetti | Angel Hair | 9.4 | 1.9 | 66.7 | Vining | 2.2 |
| Pinnacle | 3.3 | 2.6 | 36.9 | Vining | 3.2 |
| Hasta La Pasta | 5.3 | 1.8 | 37.1 | Vining | 2.5 |
| Tivoli | 2.9 | 3.7 | 37.0 | Semi-bush | 2.9 |
| Delicata (only variety) | Bush Delicata | 2.3 | 1.2 | 38.2 | Semi-bush | 4.3 |
* The intention of this study was to determine compact and high-yielding winter squash varieties for backyard gardens.
** Varieties were originally selected as those marketed as bush-types (compact).
*** Flavor was scored on a scale of 1 to 5, with 1 having poor taste and 5 being very flavorful.
Thanks to the following:
Andy Clark, ARDEC-South farm manager; the CSU Department of Horticulture and Landscape Architecture; and the many Larimer and Weld County Master Gardeners who supported this research project.
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