When to Plant Marigolds in Ross County, OH
Your June game plan for Ross County, Ohio
Your garden in Ross County, Ohio is working on a schedule, even when you're not. Here's where you should be this June.
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Start marigolds under lights
You're about 17 weeks out from your last frost — the perfect window to get these germinating indoors.
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It's harvest week for marigolds
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
Get ahead of July
- 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.
Ross County, Ohio is in USDA Zone 6b. The average last spring frost is April 22 and the first fall frost is October 21, giving you a growing season of approximately 182 days.
At an elevation of 1,322 feet, Ross County receives approximately 36.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Marigolds during the growing season.
Ross County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.8
Drainage
Well Drained
Marigolds 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 Ross County
How your county's soil matches Marigolds's growing requirements.
Soil pH
Your soil pH (6.1–6.8) is within Marigolds's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Ross County is excellent for Marigolds — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.0%) — Marigolds will thrive.
How to Plant Marigolds
Succession Planting Marigolds
Sow every 5.7 weeks. Last sowing by Aug 12 to harvest before frost.
Marigolds Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.7" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Ross 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 — Ross County, OH
Marigolds Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 11 | Mar 11 – Mar 25 |
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Direct Sow | April 22 | Apr 22 – May 13 |
| Bloom | June 17 | Jun 17 – Sep 23 |
Plant 0.3" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| 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: ideal
🗺️ USDA Zone
Zone 6b
📆 Growing Season
182 days in Ross County
Growing Tips for Marigolds in Ross County
Direct sow Marigolds outdoors after April 22 in Ross 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 Ross County, OH?
Ross County is in Zone 6b with an average last frost of April 22. Plan your Marigolds planting based on this frost date — see the calendar above for exact timing.
What planting zone is Ross County, OH?
Ross County, Ohio is in USDA Hardiness Zone 6b. The average last spring frost is April 22 and first fall frost is October 21.
Your Ross County Garden Planner — Free
A 22-page printable planner built for Ross 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.