Customer Service Hours
Mon-Fri 8-4 MST
Features
Family
Cucurbitaceae
Native
North America
Life Cycle
Annual
Plant Height
Tall (Greater than 24")
Further Information
Plant Characteristics
Good for Containers
Growing Conditions
Frost Sensitive
About Costata Romanesco Summer Squash Seeds
Cucurbita pepo
Best harvested under 12". Light gray-green fruits with lighter stripes and distinct ribbing. Good producer of male blossoms for cooking.
Planting Squash
Days to Maturity
52–60 days
Plant Spacing
2–3 seeds per mound
Light Required
Full sun
Plant Height
Tall (Greater than 24")
Planting Depth
½"–1"
Coverage & Planting Details
| Coverage | This packet sows up to 5 mounds. |
|---|---|
| Row Spacing | 3'–4' |
| Seed Depth | ½"–1" |
| Seed Spacing | 2–3 seeds per mound |
| Thinning | When 3 leaves, thin to 1 plant per mound |
| Germination | 5–10 days |
| Start Indoors | Not recommended except in very short growing seasons, 2 to 4 weeks before transplanting. Roots are sensitive to disturbance; sow in biodegradable pots that can be planted directly into the ground. Transplant when soil temperature is at least 60°F. |
| Direct Sow | RECOMMENDED. 1 to 2 weeks after your average last frost date, and when soil temperature is 70°–85°F. |
| Growing & Harvesting | Harvest frequently to increase yield; squash seem to get monstrous overnight. While edible at almost any size, seeds are less developed in young fruit, therefore more tender. Using a knife or clippers, cut squash off including some of the stem. By including stem, the fruit is sealed and less likely to mold or dry out. Harvesting Blossoms: Look for male, non-fruit producing flowers that have long stems and harvest just before use (female flowers have a swollen mini-squash at the base of the flower and are on shorter stems). |
Find Your Frost Date & Grow Zone
Average First Frost Date
October 19
Average Last Frost Date
May 19
Your Hardiness Zone is
5b
Send Your Recommendation
Total 5 star reviews: 24 Total 4 star reviews: 4 Total 3 star reviews: 1 Total 2 star reviews: 0 Total 1 star reviews: 5
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Rating
34 reviews
- Amy V.Verified BuyerRated 5 out of 5 stars6/15/26Amazing squash
This is one of the best varieties of squash I've ever grown. It is extremely prolific, and the main stem is so thick and tough, the vine borers havent been able to get into the inside of the stem. I have noticed the vine borer eggs are on the leaf stems, and i have found some of the larvae in the leaf stems, which is new to me. Amazing squash. It is June 15, and I planted in the beginning of May . They are well over 4 feet tall.
BIBotanical Interests6/16/26Hey Amy,
What an incredible success story with your Costata Romanesco! We're happy to know it's one of the best varieties you've ever grown! It's great the thick, tough main stems are keeping those pesky vine borers at bay. Super interesting that you're finding the larvae in the leaf stems instead - that's some great observational gardening right there! Your Costata Romanesco is clearly loving whatever you're doing! Thanks for sharing your amazing squash success with us! Keep on growing 🌻️
- Jasmine J.Verified ReviewerRated 5 out of 5 stars6/6/26Sturdy
Every season I've grown these, they have had great disease and pest resistance, germination, speedy growth, and tastes great - nutty flavor. This year the SVB and Squash Bugs have been bad, but these are one of the few types still going.
BIBotanical Interests6/10/26Hey Jasmine,
What a testament to the reliability of our Costata Romanesco Summer Squash Seeds! We love hearing about that consistent performance year after year - great germination, speedy growth, disease resistance, and that delicious nutty flavor. It's especially impressive that they're still thriving despite this year's tough SVB and squash bug pressure! That's exactly the kind of sturdy, dependable variety every gardener needs in their arsenal. Thanks for sharing your Costata Romanesco success with us! Keep on growing 🌻️
- JakeRated 5 out of 5 stars12/6/255 Stars
Order came very quickly!
- Margaret C.Verified BuyerRated 5 out of 5 stars11/11/25Great Squash
My favorite of all the zucchini types. Thick, meaty, lasts well and high yield.
Which best describes you as a gardener? IntermediateBIBotanical Interests11/12/25Hey Margaret,
Thank you so much for this fantastic 5-star review! "Thick, meaty, lasts well and high yield" is exactly what we love to hear about Costata Romanesco Summer Squash Seeds - and we absolutely love that you've discovered why these Italian heirloom squash have become your absolute favorite among all the zucchini types!
That's exactly the kind of superior harvest quality that makes Costata Romanesco such garden treasures! There's nothing quite like experiencing that distinctive thick, meaty texture with those beautiful ribbed edges that make these squash so much more substantial and flavorful than regular zucchini, plus that incredible keeping quality and generous production that keeps your kitchen stocked with delicious homegrown squash all season long!
Your favorite-of-all-zucchini-types experience will be so inspiring for other gardeners who want to discover just how much better Costata Romanesco Summer Squash Seeds can be compared to ordinary varieties - delivering that perfect combination of exceptional texture, outstanding storage life, and abundant yields that make these Italian beauties the ultimate choice for serious squash lovers!
Keep on growing 🌻️
- Lupe K.Verified BuyerRated 4 out of 5 stars11/7/25Huge squash
I'm in zone 10a southern Arizona. Never grown this squash before. It's so pretty, huge plant. I picked my first one last week, sitting on my counter i haven't cooked it yet. Sorry. If i can add to this later I will.
No problems with germination.
Which best describes you as a gardener? BeginnerBIBotanical Interests11/8/25Hey Lupe,
Thank you so much for this fantastic 4-star review! "Huge squash" with that "so pretty, huge plant" is exactly what we love to hear about Costata Romanesco Summer Squash Seeds - and we absolutely love that you've discovered just how impressive these Italian heirloom squash plants can grow, especially thriving there in zone 10a southern Arizona!
That's exactly the kind of vigorous growing success that makes Costata Romanesco such garden treasures! There's nothing quite like watching these distinctive ribbed squash plants develop into those massive, beautiful specimens that produce such stunning, fluted summer squash with that classic Italian appearance - and perfect germination makes it even better!
We totally understand wanting to admire that first gorgeous harvest sitting on your counter before cooking it - those beautiful ribbed Costata Romanesco squash really are something special to look at! Your huge plant success and perfect germination experience will be so inspiring for other gardeners who want to discover just how well Costata Romanesco Summer Squash Seeds can perform in hot climates for creating those impressive, productive plants that deliver such beautiful and delicious Italian heirloom squash!
Keep on growing 🌻️