When to plant Rue in Black Hawk County, IA
Black Hawk County sits in cold Zone 5a. Plant Rue May 6–May 20 for the single annual harvest; the October 7 first frost closes the window.
When to Plant Rue in Black Hawk County, IA
Top priorities for Black Hawk County, Iowa gardeners in June
Your garden in Black Hawk County, Iowa is working on a schedule, even when you're not. Here's where you should be this June.
July will be here before you know it — start on
- First harvests: rue
Rue is a bitter, aromatic perennial herb with bluish-green foliage used historically in medicine and as a pest deterrent. Handle with care as its sap can cause skin irritation.
Black Hawk County, Iowa is in USDA Zone 5a. The average last spring frost is April 29 and the first fall frost is October 7, giving you a growing season of approximately 161 days.
At an elevation of 1,380 feet, Black Hawk County receives approximately 38.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Rue to ensure they mature before fall.
Black Hawk County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.1
Drainage
Well Drained
Rue 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 Black Hawk County
How your county's soil matches Rue's growing requirements.
Soil pH
Your soil pH (6.2–7.1) is within Rue's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Black Hawk County is excellent for Rue — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — Rue will thrive.
How to Plant Rue
Succession Planting Rue
Sow every 8 weeks. Last sowing by Jul 09 to harvest before frost.
Rue Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Rue
Rue 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 | Rue Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Black Hawk County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Rue 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.
Rue Planting Timeline — Black Hawk County, IA
Rue Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 6 | May 6 – May 20 |
| Harvest | July 15 | Jul 15 – Sep 16 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 5a
📆 Growing Season
161 days in Black Hawk County
Growing Tips for Rue in Black Hawk County
Direct sow Rue outdoors after April 29 in Black Hawk County when soil has warmed and frost danger has passed.
General growing tips
Start seeds indoors or direct sow. Plant in well-drained soil. Wear gloves when handling as sap can cause phytophotodermatitis. Prune in early spring.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Rue in Other Locations
Frequently Asked Questions
When should I plant Rue in Black Hawk County, IA?
Black Hawk County is in Zone 5a with an average last frost of April 29. Plan your Rue planting based on this frost date — see the calendar above for exact timing.
What planting zone is Black Hawk County, IA?
Black Hawk County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 29 and first fall frost is October 7.
When should I plant Rue in Black Hawk County, IA?
In Black Hawk County, IA, plant Rue after the last frost (around April 29) and before the first frost (around October 7). Best results when soil holds above 50°F.
What growing zone is Black Hawk County, IA for Rue?
Black Hawk County sits in USDA Zone 5a. Rue grows reliably in zones 4a through 9b, so it's a good fit here.
Can Rue grow in Black Hawk County's climate?
Yes — Rue grows well in Black Hawk County's temperate climate. Black Hawk County averages a 161-day frost-free season, with last frost around April 29 and first frost around October 7.
Your Black Hawk County Garden Planner — Free
A 22-page printable planner built for Black Hawk 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.