What hardiness zones is Cucurbita maxima 'Hubbard' suitable for?

Cucurbita maxima 'Hubbard' is suitable for USDA hardiness zones 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b.

How much water does Cucurbita maxima 'Hubbard' need?

Cucurbita maxima 'Hubbard' has moderate to high water needs.

Annuals

Cucurbita maxima 'Hubbard'

Hubbard Winter Squash

CucurbitaceaeSouth America

At a Glance

Typeannual

Habitsprawling vine

Foliagedeciduous

Height12-18 inches

Width10-15 feet

Growing Zones

USDA Hardiness Zones

3a - 9b

Zone 3a

Zone 3b

Zone 4a

Zone 4b

Zone 5a

Zone 5b

Zone 6a

Zone 6b

Zone 7a

Zone 7b

Zone 8a

Zone 8b

Zone 9a

Zone 9b

These zones indicate the coldest temperatures this plant can typically survive.

Frost Tolerancetender

Key Features

Attracts Pollinators

Attracts Butterflies

Maintenancemoderate

Overview

Cucurbita maxima 'Hubbard' is a vigorous annual vine producing large, distinctive winter squash with exceptional storage qualities. This heirloom cultivar develops massive, ribbed fruits that can weigh 10-25 pounds or more, featuring a characteristic teardrop or turban shape with a hard, blue-gray to orange shell depending on the specific Hubbard variety. The sprawling vines can extend 10-15 feet with large, heart-shaped leaves that are deeply lobed and covered in fine hairs. The plant produces separate male and female flowers on the same vine, with bright yellow, trumpet-shaped blooms that are quite large and showy. Female flowers develop the small fruit at their base, while male flowers provide pollen for fertilization. The mature squash develops an extremely hard shell that becomes nearly impenetrable when fully cured, making Cucurbita maxima 'Hubbard' one of the premier storage varieties capable of keeping for 6-8 months in proper conditions.

Native Range

Cucurbita maxima is native to South America, specifically the Andes mountains and surrounding regions of Bolivia, northern Argentina, and southern Peru. Archaeological evidence suggests this species was first domesticated in the highlands of Bolivia and northern Argentina over 4,000 years ago.

Suggested Uses

Cucurbita maxima 'Hubbard' works well in large vegetable gardens, market gardens, and homestead settings where space allows for sprawling growth. Excellent for long-term food storage and winter cooking. The mature squash is prized for soups, pies, roasted dishes, and can be processed for freezing. Seeds are edible when roasted. Requires significant garden space but rewards growers with months of stored nutrition from a single plant.

How to Identify

Cucurbita maxima 'Hubbard' can be identified by its distinctively shaped winter squash with a hard, ribbed shell and characteristic teardrop or turban form. The fruits are much larger than most other winter squash varieties, often weighing 15-25 pounds. Key identifying features include the extremely thick, corky stem that is round and spongy rather than ridged, large heart-shaped leaves with rounded lobes, and massive yellow flowers. The mature fruit develops a very hard shell that ranges from blue-gray to deep orange, with dense, fine-textured orange flesh inside.

Appearance

Size & Dimensions

Height1' - 1'6"

Width/Spread10' - 15'

Colors

Flower Colors

yellow

Foliage Colors

green

Bloom Information

Bloom Period

~12 weeks

SummerFall

mid-summer through early fall

Detailed Descriptions

Flower Description

bright yellow

Foliage Description

medium to dark green with lighter veining

Growing Conditions

Sun Requirements

Full Sun

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 6.8(Neutral)

357912

Soil Types

loam

Drainage

well drained

Water & Climate

Water Needs

moderate to high

Frost Tolerance

tender

Time to Maturity

100-120 days

Care & Maintenance

Care Guide

Cucurbita maxima 'Hubbard' requires full sun and rich, well-draining soil with plenty of organic matter. Plant in warm soil after all danger of frost has passed and soil temperature reaches at least 60°F. Provide consistent moisture throughout the growing season, especially during fruit development, but avoid overhead watering to prevent foliar diseases. Apply a balanced fertilizer at planting and side-dress with compost or aged manure when vines begin to run. Mulch around plants to retain moisture and suppress weeds, but keep mulch away from the stem to prevent rot. As fruits develop, place them on boards or straw to prevent ground contact and potential rot.

Pruning

Cucurbita maxima 'Hubbard' requires minimal pruning but benefits from selective vine management. Remove any diseased or damaged leaves promptly to maintain plant health. For larger fruits, limit each vine to 2-3 developing squash by removing excess female flowers or small fruits. Pinch off vine tips once 2-3 fruits have set to direct energy into fruit development rather than continued vine growth. Remove male flowers after pollination is complete to reduce pest attraction and disease pressure.

Maintenance Level

moderate

⚠️ Toxicity Warning

Cucurbita maxima 'Hubbard' is non-toxic and safe for humans and pets. All parts of the mature fruit are edible, including the flesh, seeds, and even young shoots and flowers. However, like all members of the Cucurbitaceae family, avoid consuming any fruit that tastes extremely bitter, as this may indicate the presence of cucurbitacins which can cause digestive upset.

Planting Guide

Planting Methods & Timing

Planting Method

both

Indoor Start

3 weeks before last frost

Direct Sow Timing

after last frost when soil temperature reaches 60°F

Days to Maturity

100–120 days

Plant Spacing

48 inches

Companion Planting

Good Companions

corn

beans

radishes

nasturtiums

marigolds

sunflowers

Avoid Planting With

potatoes

aromatic herbs

fennel

brassicas