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When to plant Spinach in Sullivan County, IN

In Sullivan County, plant Spinach in spring between April 4 and April 25, once soil temps hold above 50°F. Sullivan County's last frost averages April 18, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between August 8 and August 22 — roughly 35–50 days before the first frost on October 17.

When to Plant Spinach in Sullivan County, IN

Spinach

Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.

Sullivan County, Indiana is in USDA Zone 6b. The average last spring frost is April 18 and the first fall frost is October 17, giving you a growing season of approximately 182 days.

At an elevation of 914 feet, Sullivan County receives approximately 34.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Spinach during the growing season.

Sullivan County, IN (Zone 6b) Moderate season
182 days
Last Spring Frost April 18
182 growing days
First Fall Frost October 17

Sullivan County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Monthly Watering Guide for Spinach

Spinach needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Spinach Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.6" 0.7" 💧 Light watering
Jun 4.3" 4.9" 0" ✅ Rainfall sufficient
Jul 4.3" 3.5" 0.8" 💧 Light watering
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 1.8" 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.

Spinach Planting Timeline — Sullivan County, IN

Spinach 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 May 23 May 23 – Jul 25
Fall Sowing August 8 Aug 8 – Aug 22

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Harvest
June Harvest
July Harvest
August Fall Sowing
September
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

182 days in Sullivan County

Growing Tips for Sullivan County

Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Spinach Seeds
Life Cycle Annual
Pollination Wind Pollinated
How to Collect Let plants bolt. Harvest seed stalks when seeds turn tan.
Storage Store airtight; viable 5 years at 35°F, under 45% humidity.

Wind pollinated — isolate 1/2 mile for purity. Easy to let bolt in heat.

Frequently Asked Questions

When should I plant Spinach in Sullivan County, IN?

Sullivan County is in Zone 6b with an average last frost of April 18. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sullivan County, IN?

Sullivan County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 18 and first fall frost is October 17.

When should I plant Spinach in Sullivan County, IN?

In Sullivan County, IN, plant Spinach after the last frost (around April 18) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Sullivan County, IN for Spinach?

Sullivan County sits in USDA Zone 6b. Spinach grows reliably in zones 2a through 10b, so it's a good fit here.

Can Spinach grow in Sullivan County's climate?

Yes — Spinach grows well in Sullivan County's temperate climate. Sullivan County averages a 182-day frost-free season, with last frost around April 18 and first frost around October 17.

🌱

Your Sullivan County Garden Planner — Free

A 22-page printable planner built for Sullivan 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.

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

Sources & credits

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