When to Plant Angelica in O'Brien County, IA
O'Brien County, Iowa gardeners: here's your April plan
Welcome to April in Zone 5a. These are the moves that will have the biggest impact on your growing season.
-
Transplant angelica outside
Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.
-
Put angelica seeds straight in the ground
Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.
Angelica is a dramatic biennial herb that can reach 6 feet tall with large compound leaves and globe-shaped flower clusters. All parts are edible with a sweet, celery-like flavor.
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 Angelica to ensure they mature before fall.
O'Brien County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-7.2
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 O'Brien County
How your county's soil matches Angelica's growing requirements.
Soil pH
Your soil pH (5.8–7.2) overlaps with Angelica's range (5.5–7.0), though not a perfect match.
Soil Texture
The silt loam soil in O'Brien County is excellent for Angelica — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.1%) — Angelica will thrive.
How to Plant Angelica
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Angelica
Angelica needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Angelica 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 | 6.5" | 5.1" | 1.4" | 💧 Light watering |
| Jun | 6.5" | 4.8" | 1.7" | 💧 Light watering |
| Jul | 6.5" | 4.5" | 2" | 💧 Light watering |
| Aug | 6.5" | 4.8" | 1.7" | 💧 Light watering |
| Sep | 6.5" | 3.2" | 3.3" | 🚿 Regular watering |
| Oct | 6.5" | 3.6" | 2.9" | 💧 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.
Angelica 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.
Angelica Planting Timeline — O'Brien County, IA
Angelica 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 |
| 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 | — |
| July | Fall Sowing |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
365–730 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
157 days in O'Brien County
Growing Tips for Angelica in O'Brien County
Direct sow Angelica outdoors after May 01 in O'Brien County when soil has warmed and frost danger has passed.
Your 157.0-day growing season in O'Brien County is tight for Angelica (365.0-730.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Angelica in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Sow fresh seeds in fall for spring germination. Provide rich, moist soil and partial shade. Harvest stems in the second year before flowering for candying or flavoring.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Angelica in Other Locations
Frequently Asked Questions
When should I plant Angelica in O'Brien County, IA?
O'Brien County is in Zone 5a with an average last frost of May 1. Plan your Angelica 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.
Your O'Brien County Garden Planner — Free
A 24-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.