When to plant Romanesco in Clark County, IL
Clark County gardeners should plant Romanesco between March 31 and April 21 in spring. With Clark County's Zone 6b climate (last frost April 14), Romanesco needs 75–100 days to mature — plant by July 9 for a full harvest. A second sowing from August 8 to August 22 extends the harvest into fall.
When to Plant Romanesco in Clark County, IL
Romanesco is a stunning brassica with a lime-green head composed of fractal-patterned spiraling florets. It has a nuttier, milder flavor than cauliflower.
Clark County, Illinois is in USDA Zone 6b. The average last spring frost is April 14 and the first fall frost is October 17, giving you a growing season of approximately 186 days.
At an elevation of 591 feet, Clark County receives approximately 41.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Romanesco during the growing season.
Clark County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Romanesco Planting Timeline — Clark County, IL
Romanesco Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 10 | Mar 10 – Mar 24 |
| Transplant Outdoors | April 14 | Apr 14 – Apr 28 |
| Direct Sow | March 31 | Mar 31 – Apr 21 |
| Harvest | June 30 | Jun 30 – Aug 11 |
| Fall Sowing | August 8 | Aug 8 – Aug 22 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
75–100 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6b
📆 Growing Season
186 days in Clark County
Growing Tips for Clark County
Start seeds indoors 5-7 weeks before transplanting. Provide consistent moisture and avoid temperature stress. Harvest when head is fully formed but before florets begin to separate.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Romanesco in Other Locations
Frequently Asked Questions
When should I plant Romanesco in Clark County, IL?
Clark County is in Zone 6b with an average last frost of April 14. Plan your Romanesco planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clark County, IL?
Clark County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 17.
When should I plant Romanesco in Clark County, IL?
In Clark County, IL, plant Romanesco after the last frost (around April 14) and before the first frost (around October 17). Best results when soil holds above 50°F.
What growing zone is Clark County, IL for Romanesco?
Clark County sits in USDA Zone 6b. Romanesco grows reliably in zones 3a through 10b, so it's a good fit here.
Can Romanesco grow in Clark County's climate?
Yes — Romanesco grows well in Clark County's temperate climate. Clark County averages a 186-day frost-free season, with last frost around April 14 and first frost around October 17.
Your Clark County Garden Planner — Free
A 22-page printable planner built for Clark County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.