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When to plant Broccoli in Sullivan County, MO

For Broccoli in Sullivan County, the safe spring window opens around April 3 and closes around April 24. Last expected frost is April 17, first fall frost October 17, giving a 183-day growing season. A second sowing from August 8 to August 22 extends the harvest into fall.

When to Plant Broccoli in Sullivan County, MO

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.

Sullivan County, Missouri is in USDA Zone 6a. The average last spring frost is April 17 and the first fall frost is October 17, giving you a growing season of approximately 183 days.

At an elevation of 1,019 feet, Sullivan County receives approximately 34.5 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.

Sullivan County, MO (Zone 6a) Moderate season
183 days
Last Spring Frost April 17
183 growing days
First Fall Frost October 17

Sullivan County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.8

Drainage

Well Drained

How Much Broccoli to Grow

1-2 lbs
Average yield per plant
3
Plants per person
6 sq ft
Space per person

For a family of 4, plant approximately 12 broccoli plants in about 24 sq ft. In Sullivan County's 183-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

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 1.4" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 4.3" 3.1" 1.2" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 4.2" 0.1" 💧 Light watering
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.2" 1.1" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 2.6" 1.7" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Sullivan County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Broccoli Planting Timeline — Sullivan County, MO

Broccoli Planting Calendar

Activity When Date Range
Start Indoors March 13 Mar 13 – Mar 27
Transplant Outdoors April 17 Apr 17 – May 1
Direct Sow April 3 Apr 3 – Apr 24
Harvest June 19 Jun 19 – Jul 31
Fall Sowing August 8 Aug 8 – Aug 22

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors
June Harvest
July Harvest
August Fall Sowing
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 6a

📆 Growing Season

183 days in Sullivan County

Growing Tips for Sullivan 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

  • Tomatoes
  • Strawberries

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Broccoli Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Allow plants to flower 2nd year; collect dry pods.
Storage Store airtight; viable 5 years at 35°F, under 50% humidity.

Isolate 1/2 mile from other brassicas. Biennial — must overwinter roots.

Frequently Asked Questions

When should I plant Broccoli in Sullivan County, MO?

Sullivan County is in Zone 6a with an average last frost of April 17. Plan your Broccoli planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sullivan County, MO?

Sullivan County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 17 and first fall frost is October 17.

When should I plant Broccoli in Sullivan County, MO?

In Sullivan County, MO, plant Broccoli after the last frost (around April 17) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Sullivan County, MO for Broccoli?

Sullivan County sits in USDA Zone 6a. Broccoli grows reliably in zones 2a through 11b, so it's a good fit here.

Can Broccoli grow in Sullivan County's climate?

Yes — Broccoli grows well in Sullivan County's temperate climate. Sullivan County averages a 183-day frost-free season, with last frost around April 17 and first frost around October 17.

🌱

Your Sullivan County Garden Planner — Free

A 22-page printable planner built for Sullivan County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Sullivan County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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