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Squash · Cucurbita pepo

Romanesco Zucchini

Romanesco Zucchini: 95 days to harvest, 7-10 days to germinate, 36-48 inches between plants, pH 6.0-7.0, hardy in zones 3-11. Fruit runs to about 24". Give it full sun (6+ hours) and 1-2 inches per week, consistent moisture water. Vining habit, so give it a frame or a trellis.

Squash
95days to harvest
7-10days to germinate
Z3–11USDA zones
Easy to moderatedifficulty
Heirloom

Sowing

Direct sow when soil reaches 65°F. Can start indoors 2-3 weeks before transplanting outdoors.

Cultivation

Sun
Full sun (6+ hours)
Water
1-2 inches per week, consistent moisture
Soil
Rich, well-drained loam with good organic matter
Soil pH
6.0-7.0
Spacing
36-48 inches
Height
1-3 feet
Season
Warm season annual

Appearance & flavour

Colour
Light green with darker green striping along ribs
Size
24"
Shape
Vining
Flavour
Nutty, sweet, and more flavorful than standard zucchini with firm texture

In the kitchen

Grilling, stuffing, ratatouille, pasta dishes, frittatas, and gourmet preparations where appearance matters

Pests, disease & resistance

Pests
Squash bug, cucumber beetle, aphids
Diseases
Powdery mildew, downy mildew, mosaic virus
Resistance
Moderate disease resistance typical of heirloom varieties

Planting calendar by USDA zone

ZoneStart indoorsTransplantDirect sowHarvest
2——June – AugustOctober – September
3——June – JulyOctober
4——June – JulySeptember – October
5——May – JuneSeptember – October
6——May – JuneSeptember – October
7——April – JuneAugust – October
8——April – MayAugust – September
9——March – AprilJuly – August
10——February – AprilJune – August
11——January – MarchMay – July
12——January – MarchMay – July
13——January – MarchMay – July

Companion planting

8 beneficial pairings indexed for this variety, 3 to avoid.

NasturtiumsAct as trap crops for squash bugs and cucumber beetles, also repel aphids
MarigoldsRepel cucumber beetles, squash bugs, and nematodes while attracting beneficial insects
RadishesDeter squash vine borers and cucumber beetles, mature quickly without competing for space
CornProvides natural trellis support and shade, creates beneficial microclimate
BeansFix nitrogen in soil for heavy-feeding squash, complement corn in three sisters planting
CatnipStrongly repels squash bugs, cucumber beetles, and other common squash pests
OreganoRepels cucumber beetles and provides ground cover to suppress weeds
DillAttracts beneficial insects like parasitic wasps that control squash pests

Avoid

PotatoesCompete for nutrients and space, both are heavy feeders that deplete soil
FennelInhibits growth through allelopathy and attracts harmful insects
Aromatic herbs (sage, rosemary)Strong essential oils can inhibit squash growth and development

Nutrition (per 100 g)

Calories (per 100 g)
21
Protein (g)
2.71
Fat (g)
0.4
Carbohydrate (g)
3.11
Fibre (g)
1.1
Vitamin A (µg)
25
Vitamin C (mg)
34.1
Vitamin B6 (mg)
0.142
Folate (µg)
20
Calcium (mg)
21
Iron (mg)
0.79
Magnesium (mg)
33
Phosphorus (mg)
93
Potassium (mg)
459
Zinc (mg)
0.83
Selenium (µg)
0.3
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Growing it? There is a full cultivation guide at the squash growing guide.

Cultivar facts compiled from public horticultural references including USDA GRIN and NC State Extension. Descriptions are original to this catalogue.

DarkGrow forum

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Similar varieties

Other squash with a comparable time to harvest, so a season that suits Romanesco Zucchini suits these too.

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