When to plant Broccoli in McHenry County, IL
Plant Broccoli in McHenry County, when soil hits 50°F — usually April 4. Continue planting through April 25 for the spring crop. A second sowing from August 11 to August 25 extends the harvest into fall.
When to Plant Broccoli in McHenry County, IL
Broccoli is a nutrient-dense cool-season crop that produces large central heads followed by smaller side shoots. It is one of the most popular garden vegetables.
McHenry County, Illinois is in USDA Zone 5b. The average last spring frost is April 18 and the first fall frost is October 20, giving you a growing season of approximately 185 days.
At an elevation of 640 feet, McHenry County receives approximately 39.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Broccoli to ensure they mature before fall.
McHenry County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
How Much Broccoli to Grow
For a family of 4, plant approximately 12 broccoli plants in about 24 sq ft. In McHenry County's 185-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Broccoli Planting Timeline — McHenry County, IL
Broccoli Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 14 | Mar 14 – Mar 28 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | April 4 | Apr 4 – Apr 25 |
| Harvest | June 20 | Jun 20 – Aug 1 |
| Fall Sowing | August 11 | Aug 11 – Aug 25 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| 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
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
185 days in McHenry County
Growing Tips for McHenry County
Start seeds indoors 6-8 weeks before last frost. Provide consistent moisture to prevent hollow stems. Harvest heads before yellow flowers appear.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 1/2 mile from other brassicas. Biennial — must overwinter roots.
Broccoli in Other Locations
Frequently Asked Questions
When should I plant Broccoli in McHenry County, IL?
McHenry County is in Zone 5b with an average last frost of April 18. Plan your Broccoli planting based on this frost date — see the calendar above for exact timing.
What planting zone is McHenry County, IL?
McHenry County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 18 and first fall frost is October 20.
When should I plant Broccoli in McHenry County, IL?
In McHenry County, IL, plant Broccoli after the last frost (around April 18) and before the first frost (around October 20). Best results when soil holds above 50°F.
What growing zone is McHenry County, IL for Broccoli?
McHenry County sits in USDA Zone 5b. Broccoli grows reliably in zones 2a through 11b, so it's a good fit here.
Can Broccoli grow in McHenry County's climate?
Yes — Broccoli grows well in McHenry County's temperate climate. McHenry County averages a 185-day frost-free season, with last frost around April 18 and first frost around October 20.
Your McHenry County Garden Planner — Free
A 22-page printable planner built for McHenry County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.