When to plant Broccoli in DuPage County County,
DuPage County County's spring Broccoli window runs April 9 through April 30. time plantings around the expected last-frost window for best survival. A second sowing from August 8 to August 22 extends the harvest into fall.
When to Plant Broccoli in DuPage County, IL
Your June game plan for DuPage County, Illinois
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
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Basket week: broccoli
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
July will be here before you know it — start on
- First harvests: broccoli
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.
DuPage County, Illinois is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 17, giving you a growing season of approximately 177 days.
At an elevation of 803 feet, DuPage County receives approximately 31 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Broccoli to ensure they mature before fall.
DuPage County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.7
Drainage
Well Drained
Broccoli Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in DuPage County
How your county's soil matches Broccoli's growing requirements.
Soil pH
Your soil pH (6.0–6.7) is within Broccoli's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in DuPage County is excellent for Broccoli — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.0%) — Broccoli will thrive.
How to Plant Broccoli
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Broccoli
Sow every 6.9 weeks. Last sowing by Jul 19 to harvest before frost.
For a dedicated fall crop, sow by Aug 08.
Broccoli Water Budget
Monthly Watering Guide for Broccoli
Broccoli needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Broccoli Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3" | 1.3" | 💧 Light watering |
| May | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Jun | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Aug | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Sep | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Oct | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Nov | — | 2.3" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in DuPage County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Broccoli Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Broccoli Planting Timeline — DuPage County, IL
Broccoli Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Harvest | June 25 | Jun 25 – Aug 6 |
| 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 |
| April | Start Indoors 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
1"/week · Only during dry spells
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
177 days in DuPage County
Growing Tips for Broccoli in DuPage County
Direct sow Broccoli outdoors after April 23 in DuPage County when soil has warmed and frost danger has passed.
Common pests for Broccoli in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
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 DuPage County, IL?
DuPage County is in Zone 5b with an average last frost of April 23. Plan your Broccoli planting based on this frost date — see the calendar above for exact timing.
What planting zone is DuPage County, IL?
DuPage County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 17.
When should I plant Broccoli in DuPage County, ?
In DuPage County, , plant Broccoli after the last frost (around April 23) and before the first frost (around October 17). Best results when soil holds above 50°F.
What growing zone is DuPage County, for Broccoli?
DuPage 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 DuPage County's climate?
Yes — Broccoli grows well in DuPage County's temperate climate. DuPage County averages a 177-day frost-free season, with last frost around April 23 and first frost around October 17.
Your DuPage County Garden Planner — Free
A 22-page printable planner built for DuPage 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.