Cucurbita pepo 'Costata Romanesco'
Costata Romanesco Zucchini
Italian heirloom from Rome (Romanesco = of Rome, costata = ribbed); the species C. pepo is native to Mexico and Central AmericaOverview
Cucurbita pepo 'Costata Romanesco' is Costata Romanesco zucchini (ribbed Roman zucchini), a bush-type summer squash annual growing 24-30 inches (60-75 cm) tall and 36-48 inches (90-120 cm) wide. Grey-green fruit with pronounced longitudinal ribs — when sliced crosswise the cross-section is star- or flower-shaped. Harvest young at 6-8 inches (15-20 cm) for tender summer squash, or allow to mature to 12-15 inches (30-38 cm) and 3-5 pounds (1.4-2.3 kg) for firmer flesh. The flesh is denser, nuttier, and less watery than standard smooth zucchini. Large edible yellow-orange trumpet-shaped monoecious flowers. Dark green palmate foliage with silvery vein mottling. In the gourd family (Cucurbitaceae). Italian heirloom from Rome (Romanesco = of Rome, costata = ribbed). Open-pollinated: seed can be saved. Monoecious: requires bee pollination — male flowers appear 7-10 days before the first female flowers. The edible male flowers are used for stuffed squash blossoms (fiori di zucca). Not a storage squash — use fresh (summer squash). Powdery mildew (Podosphaera xanthii) and squash vine borer (Melittia cucurbitae) are the primary threats. Not deer-resistant. Non-toxic (edible crop). Full sun. Tender annual. Growth rate is fast.
Native Range
Italian heirloom from Rome (Romanesco = of Rome, costata = ribbed). The species C. pepo is native to Mexico and Central America.Suggested Uses
Grown in vegetable gardens and containers of at least 10 gallons (38 L). Bush type. The ribbed star cross-section and the dense nutty flesh. Edible flowers for stuffing (fiori di zucca). Italian heirloom. Open-pollinated — save seeds. Non-toxic. Tender annual.How to Identify
Appearance
Size & Dimensions
Height2' - 2'6"
Width/Spread3' - 4'
Reaches mature size in approximately 1 years
Bloom Information
Summer (June-September). Large yellow-orange trumpet-shaped monoecious flowers. Male flowers appear first. Requires bee pollination. Male flowers are edible (stuffed squash blossoms). Fruit 52-60 days from seed.Detailed Descriptions
Flower Description
Yellow-orange, trumpet-shaped, 4-5 inches (10-12 cm); monoecious; male flowers on longer stems, female with miniature fruit at baseFoliage Description
Dark green, large palmate, 10-14 inches (25-35 cm) across, with silvery mottling along veins; on thick upright stemsGrowing Conditions
Sun Requirements
Requires 8-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Full sun (8+ hours). Rich moist well-drained soil pH 6.0-7.0. Heavy feeder — side-dress with compost. Consistent moisture. Requires bee pollination. Harvest every 2-3 days. Powdery mildew and squash vine borer. Not a storage squash. Not deer-resistant. Non-toxic. Tender annual.Pruning
Remove lower leaves that touch soil to reduce disease and improve air circulation. Harvest fruit every 2-3 days. No other pruning on bush types.Maintenance Level
moderateContainer Growing
✓ Suitable for container growing
Minimum container size: 10 gallons
⚠️ Toxicity Warning
Non-toxicPlanting Guide
Planting Methods & Timing
Planting Method
both
Indoor Start
4 weeks before last frost
Direct Sow Timing
After last frost when soil temperature reaches 65 degrees F (18 degrees C)+
Days to Maturity
52–60 days
Plant Spacing
36 inches