Butternut Squash Seeds - Waltham Butternut - Cucurbita moschata

2, 3, 4, 5, 6, 7, 8, 9, 10, 11

USDA Zones 2-11 - Grows as a warm-season annual in all zones. Butternut squash is not frost-hardy and requires a long, warm growing season.

Best performance in Zones 3-10 where long, warm summers provide the ideal conditions for ripening the fruit before the first frost.

Northern zones (2-5) - Start seeds indoors 3-4 weeks before the last expected frost date to extend the growing season. Use season extenders or row covers to protect young plants if necessary. Direct sow after all danger of frost has passed.

Hot climate zones (9-11) - Plant in early spring for a summer harvest. In desert regions with extreme heat, providing some afternoon shade can prevent stress.

Soil temperature critical - Requires warm soil for germination. Sow seeds after the soil has warmed to at least 65F, with optimal soil temperature of 70-95F for quick sprouting.

Growing season needs - Requires 85-110 days to maturity from seed, making it suitable for all zones when planted at the appropriate time.

Learn more about USDA Hardiness Zones here

When to Plant:
Direct sow seeds outdoors after all danger of frost has passed and the soil has warmed to at least 65F. For a jump start in cooler climates, you can start seeds indoors in peat pots or other biodegradable containers 3-4 weeks before your last frost date. This is important as squash seedlings do not like to have their roots disturbed.

Location and Soil:
Choose a location that receives full sun (at least 6-8 hours of direct sunlight per day). Butternut squash thrives in rich, well-draining soil with a good amount of organic matter. A soil pH between 6.0 and 6.8 is ideal.

Sowing Seeds:

Prepare the garden bed by creating small mounds or hills about 3-4 feet apart.

Sow 3-4 seeds per hill, planting them 1 inch deep.

Water thoroughly to moisten the soil.

Once the seedlings have their first true leaves, thin to the strongest 1-2 plants per hill.

Care and Maintenance:

Watering: Provide consistent and deep watering, especially during flowering and fruit development. Water at the base of the plant to keep the leaves dry, which helps prevent powdery mildew.

Fertilizing: Amend the soil with compost or well-rotted manure before planting. A balanced, all-purpose fertilizer can be applied once a month if needed.

Mulching: Apply a 2-3 inch layer of mulch around the plants to conserve moisture, suppress weeds, and keep the fruits clean.

Pests and Diseases: While 'Waltham Butternut' is known for its resistance, monitor for pests like squash bugs. Powdery mildew can be an issue in humid conditions; ensure good air circulation.

Harvesting and Storage:
Harvest when the squash reaches its mature color (a deep, uniform tan) and the rind is hard enough that it cannot be easily punctured with a thumbnail. Cut the squash from the vine, leaving 2-3 inches of stem attached to the fruit to prevent rot. Cure the harvested squash in a warm, dry location for about 1-2 weeks. Store in a cool, dark, and dry place (around 50-55F) for long-term storage.