Variety field guide
What to expect from Costata Romanesco Zucchini
Costata Romanesco is an Italian zucchini known for pronounced ribs, gray-green skin and pale flecks.
Open the complete descriptionHide the complete descriptionVariety traits, flavor, garden use, and the complete description
Costata Romanesco is an Italian zucchini known for pronounced ribs, gray-green skin and pale flecks. Its firm flesh has a rich, nutty flavor, making tender young fruit especially good grilled, sauteed or sliced raw. The ribs give cut rounds a scalloped outline, and the large blossoms can be stuffed or fried. These are substantial, spreading plants with broad leaves and spiny stems; allow room to reach the fruit and enjoy frequent small harvests.
Minimum seeds per packet: 25 seeds.
Ribbed Italian zucchini with rich flavor and edible blossoms.
Variety and background
Costata Romanesco is a large, semi-vining zucchini that needs more room than a compact bush squash.
Growing facts
| Scientific name | Cucurbita pepo L. |
|---|---|
| Life cycle | Annual |
| Maturity / harvest basis | 50-59 Days |
| Seed depth | 1 in |
| Germination | 7-10 days |
| Germination temperature | 75-90 F |
| Plant height / spread | 25–30 in |
| Habit | Large semi-vining plants |
| Plant spacing | 24 in |
| Row spacing | 72 in |
| Sunlight | Full sun |
| Pollination type | Open-Pollinated (OP) |
Starting from seed
Direct sow after frost, 1 in. deep in warm soil, or start indoors 2-3 weeks before setting out. At 75-90 F allow 7-10 days. Set 24 in. apart, rows 6 ft. apart. Give sun, fertile soil and even water. Remove row covers when flowers open.
Planting and care
Direct sow after frost, 1 in. deep in warm soil, or start indoors 2-3 weeks before setting out. At 75-90 F allow 7-10 days. Set 24 in. apart, rows 6 ft. apart. Give sun, fertile soil and even water. Remove row covers when flowers open. Costata Romanesco is a large, semi-vining zucchini that needs more room than a compact bush squash.
Harvest and use
Check near 52 days from sowing. Clip tender 6-8 in. fruit; refrigerate. Leave male flowers for pollination. For seed, isolate other C. pepo; let fruit grow fully mature with hard rinds, then wash and dry seeds.
Saving seed
Seed saving for Costata Romanesco Select several healthy, true-to-type plants so the saved lot represents the variety rather than one unusually early or large individual. Squash and gourds are insect-pollinated and cross readily with other varieties of the same species. Confirm the species identified for this crop, then isolate by distance or controlled hand pollination. Mark seed fruit and let it reach full biological maturity; summer squash must become large and hard, winter squash must develop full rind color, and luffa or hard-shell gourds must mature well beyond the edible stage. Cure sound fruit before extraction when the crop benefits from curing. Remove, wash, and dry seed to a hard, storage-ready condition. Maintain several representative plants and record species, population, isolation, fruit selection, curing, cleaning, and test date.
Common problems
Watch Costata Romanesco for cucumber beetles, squash bugs where applicable, aphids, powdery or downy mildew, bacterial wilt, crown rot, poor pollination, and fruit damage on wet soil. Rotate cucurbit crops, provide airflow, water at the root zone, protect young plants before flowering, and remove covers when blossoms need pollinators. Do not work wet vines.
Frequently asked questions
What distinguishes this selection?
Costata Romanesco is a large, semi-vining zucchini that needs more room than a compact bush squash.
How should I start it?
Direct sow after frost, 1 in. deep in warm soil, or start indoors 2-3 weeks before setting out. At 75-90 F allow 7-10 days. Set 24 in. apart, rows 6 ft. apart. Give sun, fertile soil and even water. Remove row covers when flowers open.
When and how should I harvest?
Check near 52 days from sowing. Clip tender 6-8 in. fruit; refrigerate. Leave male flowers for pollination. For seed, isolate other C. pepo; let fruit grow fully mature with hard rinds, then wash and dry seeds.
Can I save seed?
Seed saving for Costata Romanesco Select several healthy, true-to-type plants so the saved lot represents the variety rather than one unusually early or large individual. Squash and gourds are insect-pollinated and cross readily with other varieties of the same species. Confirm the species identified for this crop, then isolate by distance or controlled hand pollination. Mark seed fruit and let it reach full biological maturity; summer squash must become large and hard, winter squash must develop full rind color, and luffa or hard-shell gourds must mature well beyond the edible stage. Cure sound fruit before extraction when the crop benefits from curing. Remove, wash, and dry seed to a hard, storage-ready condition. Maintain several representative plants and record species, population, isolation, fruit selection, curing, cleaning, and test date.
