When to plant Cosmos in LaGrange County, IN
LaGrange County's spring Cosmos window runs April 28 through May 19. time plantings around the expected last-frost window for best survival.
When to Plant Cosmos in LaGrange County, IN
August to-do list for LaGrange County, Indiana
Your LaGrange County, Indiana garden is entering a new phase. Here's what's on the schedule for August and why each task matters now.
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Start harvesting cosmos
If you can't use it all right away, check the food-preservation section of your planner.
Looking ahead to September
- First harvests: cosmos
Cosmos (Cosmos bipinnatus) is an airy, feathery-foliaged cottage garden annual from Mexico that thrives on neglect. It produces delicate daisy-like blooms in shades of pink, white, and magenta from midsummer until frost. Cosmos is a prolific self-sower — once established in a garden it often returns year after year without replanting. Excellent habitat plant for beneficial insects.
LaGrange County, Indiana is in USDA Zone 6a. The average last spring frost is April 28 and the first fall frost is October 16, giving you a growing season of approximately 171 days.
At an elevation of 651 feet, LaGrange County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Cosmos during the growing season.
LaGrange County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.1
Drainage
Well Drained
Cosmos 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 LaGrange County
How your county's soil matches Cosmos's growing requirements.
Soil pH
Your soil pH (5.9–7.1) overlaps with Cosmos's range (6.0–8.0), though not a perfect match.
Soil Texture
The silt loam soil in LaGrange County is excellent for Cosmos — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Cosmos will thrive.
How to Plant Cosmos
Succession Planting Cosmos
Sow every 6.9 weeks. Last sowing by Jul 18 to harvest before frost.
Cosmos Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Cosmos
Cosmos 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 | Cosmos Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.8" | 0" | ❄️ Dormant |
| Apr | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.8" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in LaGrange County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cosmos 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.
Cosmos Planting Timeline — LaGrange County, IN
Cosmos Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 31 | Mar 31 – Apr 14 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 28 | Apr 28 – May 19 |
| Bloom | July 7 | Jul 7 – Oct 13 |
Plant 0.3" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–8 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
171 days in LaGrange County
Growing Tips for Cosmos in LaGrange County
Direct sow Cosmos outdoors after April 28 in LaGrange County when soil has warmed and frost danger has passed.
Common pests for Cosmos 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; cosmos germinates readily at 65-80°F in 7-10 days. Avoid rich soil — excess fertility produces lush foliage at the expense of blooms. Cosmos tolerates poor, dry soil exceptionally well. Pinch seedlings at 8 inches to encourage branching. Self-sows freely; allow some seed heads to mature and drop for a no-fuss perennial effect in warm climates.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Cosmos in Other Locations
Frequently Asked Questions
When should I plant Cosmos in LaGrange County, IN?
LaGrange County is in Zone 6a with an average last frost of April 28. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.
What planting zone is LaGrange County, IN?
LaGrange County, Indiana is in USDA Hardiness Zone 6a. The average last spring frost is April 28 and first fall frost is October 16.
When should I plant Cosmos in LaGrange County, IN?
In LaGrange County, IN, plant Cosmos after the last frost (around April 28) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is LaGrange County, IN for Cosmos?
LaGrange County sits in USDA Zone 6a. Cosmos grows reliably in zones 2a through 11b, so it's a good fit here.
Can Cosmos grow in LaGrange County's climate?
Yes — Cosmos grows well in LaGrange County's temperate climate. LaGrange County averages a 171-day frost-free season, with last frost around April 28 and first frost around October 16.
Your LaGrange County Garden Planner — Free
A 22-page printable planner built for LaGrange 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.