When to Plant Kale in Webster County, IA
Kale is an exceptionally hardy, nutrient-dense green available in curly, lacinato, and Russian varieties. It tolerates heavy frost and often tastes sweeter after cold exposure.
Webster County, Iowa is in USDA Zone 4b. The average last spring frost is April 28 and the first fall frost is October 6, giving you a growing season of approximately 161 days.
At an elevation of 1,065 feet, Webster County receives approximately 30.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Kale to ensure they mature before fall.
Webster County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.3
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 Webster County
How your county's soil matches Kale's growing requirements.
Soil pH
Your soil pH (6.2–7.3) is within Kale's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Webster County is excellent for Kale — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Kale.
Organic Matter
Organic matter is excellent (4.4%) — Kale will thrive.
How to Plant Kale
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Kale
Sow every 5.7 weeks. Last sowing by Jul 28 to harvest before frost.
For a dedicated fall crop, sow by Jul 14.
Plant Water Budget
Monthly Watering Guide for Kale
Kale needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.
| Month | Kale Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 3.5" | 2.6" | 0.9" | 💧 Light watering |
| May | 3.5" | 3.4" | 0.1" | 💧 Light watering |
| Jun | 3.5" | 3.6" | 0" | ✅ Rainfall sufficient |
| Jul | 3.5" | 3.1" | 0.4" | 💧 Light watering |
| Aug | 3.5" | 3" | 0.5" | 💧 Light watering |
| Sep | 3.5" | 3.2" | 0.3" | 💧 Light watering |
| Oct | 3.5" | 2.5" | 1" | 💧 Light watering |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Webster County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kale 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.
Kale Planting Timeline — Webster County, IA
Kale Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 17 | Mar 17 – Mar 31 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 21 | Apr 21 – May 12 |
| Harvest | June 23 | Jun 23 – Aug 18 |
| Fall Sowing | July 14 | Jul 14 – Jul 28 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Only during dry spells
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 4b
📆 Growing Season
161 days in Webster County
Growing Tips for Kale in Webster County
Direct sow Kale outdoors after April 28 in Webster County when soil has warmed and frost danger has passed.
Common pests for Kale in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow or transplant in early spring or late summer. Harvest outer leaves first to keep plants productive. Kale overwinters in many climates and can provide greens all year.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 1/2 mile from other brassicas (broccoli, cabbage, etc.) — they all cross.
Kale in Other Locations
Frequently Asked Questions
When should I plant Kale in Webster County, IA?
Webster County is in Zone 4b with an average last frost of April 28. Plan your Kale planting based on this frost date — see the calendar above for exact timing.
What planting zone is Webster County, IA?
Webster County, Iowa is in USDA Hardiness Zone 4b. The average last spring frost is April 28 and first fall frost is October 6.
Plan Your Garden with Confidence
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