When to Plant Marigolds in Ohio County, IN
This month in Ohio County, Indiana
Each item below is timed to Ohio County, Indiana's frost dates and soil temperatures. Skip nothing, stress about nothing.
To set up a strong June, finish these tasks
- First harvests: marigolds
Marigolds (Tagetes patula) are warm-season annuals beloved for their cheerful orange, yellow, and red blooms — and for their well-documented ability to repel pest nematodes in vegetable beds. Easy from seed, drought-tolerant once established, and bloom from early summer until the first hard frost.
Ohio County, Indiana is in USDA Zone 6b. The average last spring frost is April 17 and the first fall frost is October 19, giving you a growing season of approximately 185 days.
At an elevation of 882 feet, Ohio County receives approximately 33.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Marigolds during the growing season.
Ohio County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.1
Drainage
Well Drained
Plant 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 Ohio County
How your county's soil matches Marigolds's growing requirements.
Soil pH
Your soil pH (5.7–7.1) overlaps with Marigolds's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Ohio County is excellent for Marigolds — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Marigolds.
Organic Matter
Organic matter is excellent (4.6%) — Marigolds will thrive.
How to Plant Marigolds
Succession Planting Marigolds
Sow every 5.7 weeks. Last sowing by Aug 10 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Marigolds
Marigolds needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Marigolds Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Ohio County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Marigolds 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.
Marigolds Planting Timeline — Ohio County, IN
Marigolds Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 29 | May 29 – Jun 12 |
| Transplant Outdoors | April 17 | Apr 17 – May 1 |
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | June 12 | Jun 12 – Sep 18 |
Plant 0.3" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Start Indoors Harvest |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
185 days in Ohio County
Growing Tips for Marigolds in Ohio County
Direct sow Marigolds outdoors after April 17 in Ohio County when soil has warmed and frost danger has passed.
Common pests for Marigolds in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct-sow after last frost or start indoors 4-6 weeks earlier. Deadhead spent blooms to keep new flowers coming. French marigolds (T. patula) are the most reliable nematode repellents — plant a band around vegetable beds. Tolerate poor soil but bloom best with monthly compost.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Very easy to save. Seeds are the long, thin, dark pieces inside the dried flower head.
Marigolds in Other Locations
Frequently Asked Questions
When should I plant Marigolds in Ohio County, IN?
Ohio County is in Zone 6b with an average last frost of April 17. Plan your Marigolds planting based on this frost date — see the calendar above for exact timing.
What planting zone is Ohio County, IN?
Ohio County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 17 and first fall frost is October 19.
Your Ohio County Garden Planner — Free
A 24-page printable planner built for Ohio 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.