When to Plant Caraway in Mills County, IA
Caraway is a biennial herb grown for its distinctive crescent-shaped seeds used in rye bread, sauerkraut, and European cuisine. The leaves and roots are also edible.
Mills County, Iowa is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 7, giving you a growing season of approximately 164 days.
At an elevation of 1,355 feet, Mills County receives approximately 35.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Caraway during the growing season.
Mills County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-6.8
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 Mills County
How your county's soil matches Caraway's growing requirements.
Soil pH
Your soil pH (6.3–6.8) is within Caraway's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Mills County is excellent for Caraway — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Caraway.
Organic Matter
Organic matter is excellent (4.1%) — Caraway will thrive.
How to Plant Caraway
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Caraway
Caraway needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Caraway Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3" | 1.3" | 💧 Light watering |
| May | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Nov | — | 2.3" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Mills County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Caraway 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.
Caraway Planting Timeline — Mills County, IA
Caraway Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 22 | Mar 22 – Apr 5 |
| Transplant Outdoors | April 19 | Apr 19 – May 3 |
| Direct Sow | April 12 | Apr 12 – May 3 |
| Fall Sowing | July 29 | Jul 29 – Aug 12 |
Plant 0.5" deep · 8" apart · Rows 12" 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 | Fall Sowing |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
365–450 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
164 days in Mills County
Growing Tips for Caraway in Mills County
Direct sow Caraway outdoors after April 26 in Mills County when soil has warmed and frost danger has passed.
Your 164.0-day growing season in Mills County is tight for Caraway (365.0-450.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Caraway in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in spring or fall. Caraway produces seeds in its second year. Harvest seed heads when they turn brown. The young leaves can be used like parsley.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Caraway in Other Locations
Frequently Asked Questions
When should I plant Caraway in Mills County, IA?
Mills County is in Zone 5b with an average last frost of April 26. Plan your Caraway planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mills County, IA?
Mills County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 7.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Mills County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.