Heirloom

Hubbard Blue Squash

Cucurbita maxima 'Blue Hubbard'

A massive heirloom winter squash that can reach 40+ pounds, prized for its incredible storage life and sweet, fine-textured orange flesh. This impressive variety with its distinctive blue-gray bumpy skin has been a homestead favorite since the 1890s, providing months of nutritious meals from a single harvest. The ultimate storage squash that gets sweeter with time and can last 6-8 months when properly cured.

Harvest

100-120d

Days to harvest

📅

Sun

koo-KER-bih-ta MAKS-ih-muh

☀️

Zones

3–11

USDA hardiness

🗺️

Difficulty

Moderate

🌱

Planting Timeline

Zone:

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Direct Sow

Harvest

Direct Sow

Harvest

Showing dates for Hubbard Blue Squash in USDA Zone 7

All Zone 7 squash →

Zone Map

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Hubbard Blue Squash · Zones 3–11

What grows well in Zone 7? →

Growing Details

Difficulty

Moderate

Spacing72-96 inches (vines spread 10-15 feet)

SoilRich, well-drained soil with high organic matter content

pH6.0-7.0

Water1-2 inches per week, reduce watering as fruits mature

SeasonWarm season

FlavorSweet, nutty, and rich with fine, smooth texture

ColorBlue-gray exterior with bright orange interior flesh

Size15-40+ pounds

Zone-by-Zone Planting Calendar

Zone	Indoor Start	Transplant	Direct Sow	Harvest
Zone 3	—	—	June – July	October – October
Zone 4	—	—	June – July	October – October
Zone 5	—	—	May – June	October – October
Zone 6	—	—	May – June	September – November
Zone 7	—	—	April – June	September – October
Zone 8	—	—	April – May	August – October
Zone 9	—	—	March – April	July – September
Zone 10	—	—	February – April	July – August

Complete Growing Guide

Light: koo-KER-bih-ta MAKS-ih-muh. Soil: High Organic Matter, Loam (Silt). Soil pH: Neutral (6.0-8.0). Drainage: Good Drainage, Moist. Spacing: 12 inches-3 feet. Growth rate: Rapid. Maintenance: Medium. Propagation: Seed. Regions: Coastal, Mountains, Piedmont.

Harvesting

Soft or hard-shelled berries called pepos come in a variety of colors, shapes, and sizes and are harvested in the fall. The stems of the fruits generally have a soft corky texture compared to other species.

Color: Blue, Cream/Tan, Gold/Yellow, Gray/Silver, Orange, Pink, Red/Burgundy, Variegated, White. Type: Berry. Length: > 3 inches. Width: > 3 inches.

Garden value: Edible, Long-lasting, Showy

Harvest time: Fall

Bloom time: Summer

Storage & Preservation

Cure freshly harvested Hubbard Blue squash in a warm, dry location (80-85°F) for 10-14 days to harden the skin and heal minor scratches. After curing, store in a cool, dry place (50-55°F) with good air circulation — basements, root cellars, or unheated garages work well. Properly cured specimens last 6-8 months, actually improving in flavor as starches convert to sugars.

Check stored squash monthly, using any showing soft spots immediately. For preservation, cut into chunks and freeze raw for up to 12 months, or roast and puree before freezing for easier use in soups and baking. Pressure canning cubed squash preserves the firm texture better than water bath methods. The dense flesh also dehydrates well when sliced thin and dried at 125°F until leathery.

History & Origin

Origin: Central and South America

Advantages

+Fast-growing

Companion Plants

Plant Together

Nasturtiums

Trap crop for squash bugs and cucumber beetles, repels aphids

Marigolds

Repel cucumber beetles, squash bugs, and nematodes with their strong scent

Radishes

Deter squash vine borers and cucumber beetles, mature quickly without competing

Corn

Provides natural trellis support and shade, part of Three Sisters planting

Beans

Fix nitrogen in soil for heavy-feeding squash, traditional Three Sisters companion

Catnip

Strongly repels squash bugs, cucumber beetles, and other squash pests

Oregano

Repels cucumber beetles and provides ground cover to retain soil moisture

Sunflowers

Attract beneficial insects and pollinators while providing windbreak protection

Keep Apart

Potatoes

Compete for space and nutrients, both are heavy feeders with similar root zones

Fennel

Allelopathic effects inhibit squash growth and development

Aromatic herbs (mint family)

Strong oils can inhibit squash germination and early growth

Nutrition Facts

Calories

26kcal(1%)

Protein

0.52g(1%)

Carbs

5.64g(2%)

Fat

0.2g(0%)

Vitamin C

4.5mg(5%)

Iron

0.17mg(1%)

Calcium

9mg(1%)

Potassium

205mg(4%)

Per 100g serving. % Daily Value based on 2,000 calorie diet. Source: USDA FoodData Central (FDC #168040)

Pests & Disease Resistance

Resistance

Good natural resistance to storage rots when properly cured

Common Pests

Squash bugs, cucumber beetles, squash vine borers

Diseases

Powdery mildew, bacterial wilt, black rot in storage

Frequently Asked Questions

How long does Hubbard Blue squash take to grow?▼

Hubbard Blue squash requires 100-120 days from seed to harvest, making it one of the longer-season winter squash varieties. In shorter growing zones (3-5), start seeds indoors 2-3 weeks before the last frost to ensure adequate growing time. The long season is necessary to develop the thick, hard shell that enables their exceptional 6-8 month storage life.

Can you grow Hubbard Blue squash in containers?▼

Hubbard Blue squash is not suitable for container growing due to its massive space requirements and vine spread of 10-15 feet. Each plant needs 100-150 square feet of growing area and produces fruits weighing 40+ pounds. Even the largest containers cannot accommodate the extensive root system and vine growth necessary for proper fruit development.

What does Hubbard Blue squash taste like?▼

Hubbard Blue squash has a sweet, nutty flavor with rich, fine-textured orange flesh similar to a cross between sweet potato and butternut squash. The flavor actually improves during storage as starches convert to sugars over time. The dense, smooth flesh makes it excellent for roasting, baking, soups, and pies with minimal stringiness or wateriness.

When should I plant Hubbard Blue squash seeds?▼

Plant Hubbard Blue squash after soil temperature reaches 65°F consistently. In zones 3-5, start seeds indoors 2-3 weeks before the last frost date due to the long growing season required. Zones 6-9 can direct sow in late spring. The key is ensuring 100-120 frost-free days for proper maturation and storage quality.

Is Hubbard Blue squash good for beginners?▼

Hubbard Blue squash is moderately challenging for beginners due to its space requirements, long growing season, and susceptibility to squash vine borers. However, it's forgiving once established and doesn't require complex pruning or staking. New gardeners with adequate space and patience often find success, especially in zones 6-8 with longer growing seasons.

How do you know when Hubbard Blue squash is ripe?▼

Hubbard Blue squash is ripe when the skin becomes completely hard and cannot be dented with your fingernail, the stem attachment point turns dry and corky, and the vine begins dying back naturally. This occurs 100-120 days after planting. The distinctive blue-gray skin should have a matte finish rather than glossy appearance when fully mature.