When to plant Chamomile in O'Brien County, IA
Spring Chamomile in O'Brien County goes in April 17–May 8, once nighttime temps stop dipping near freezing. A second sowing from July 27 to August 10 extends the harvest into fall.
When to Plant Chamomile in O'Brien County, IA
Chamomile is a daisy-like herb famous for its calming, apple-scented tea. German chamomile is an annual while Roman chamomile is a perennial ground cover.
O'Brien County, Iowa is in USDA Zone 5a. The average last spring frost is May 1 and the first fall frost is October 5, giving you a growing season of approximately 157 days.
At an elevation of 658 feet, O'Brien County receives approximately 40.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Chamomile to ensure they mature before fall.
O'Brien County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-7.2
Drainage
Well Drained
Monthly Watering Guide for Chamomile
Chamomile needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Chamomile Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | — | 3.8" | 0" | ❄️ Dormant |
| May | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in O'Brien County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Chamomile Planting Timeline — O'Brien County, IA
Chamomile Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 27 | Mar 27 – Apr 10 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | June 26 | Jun 26 – Sep 4 |
| Fall Sowing | July 27 | Jul 27 – Aug 10 |
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 | Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 5.6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
157 days in O'Brien County
Growing Tips for O'Brien County
Direct sow on the soil surface as seeds need light. Harvest flowers when petals begin to curl back. Chamomile self-sows freely and improves the health of nearby plants.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Chamomile in Other Locations
Frequently Asked Questions
When should I plant Chamomile in O'Brien County, IA?
O'Brien County is in Zone 5a with an average last frost of May 1. Plan your Chamomile planting based on this frost date — see the calendar above for exact timing.
What planting zone is O'Brien County, IA?
O'Brien County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is May 1 and first fall frost is October 5.
When should I plant Chamomile in O'Brien County, IA?
In O'Brien County, IA, plant Chamomile after the last frost (around May 1) and before the first frost (around October 5). Best results when soil holds above 50°F.
What growing zone is O'Brien County, IA for Chamomile?
O'Brien County sits in USDA Zone 5a. Chamomile grows reliably in zones 3a through 9b, so it's a good fit here.
Can Chamomile grow in O'Brien County's climate?
Yes — Chamomile grows well in O'Brien County's temperate climate. O'Brien County averages a 157-day frost-free season, with last frost around May 1 and first frost around October 5.
Your O'Brien County Garden Planner — Free
A 22-page printable planner built for O'Brien County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.