When to Plant Lettuce in Lee County, IA
Lettuce is a fast-growing cool-season green available in leaf, romaine, butterhead, and crisphead types. It is the foundation of salads and one of the easiest crops to grow.
Lee County, Iowa is in USDA Zone 5b. The average last spring frost is April 16 and the first fall frost is October 18, giving you a growing season of approximately 185 days.
At an elevation of 1,393 feet, Lee County receives approximately 36.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Lettuce to ensure they mature before fall.
Lee County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.2
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 Lee County
How your county's soil matches Lettuce's growing requirements.
Soil pH
Your soil pH (6.1–7.2) overlaps with Lettuce's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Lee County is excellent for Lettuce — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Lettuce.
Organic Matter
Organic matter is excellent (4.4%) — Lettuce will thrive.
How to Plant Lettuce
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Lettuce
Sow every 3.4 weeks. Last sowing by Aug 19 to harvest before frost.
For a dedicated fall crop, sow by Aug 09.
Plant Water Budget
Monthly Watering Guide for Lettuce
Lettuce needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Lettuce Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.9" | 0" | ❄️ Dormant |
| Apr | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| May | 3" | 4.2" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 2.9" | 0.1" | 💧 Light watering |
| Oct | 3" | 2.9" | 0.1" | 💧 Light watering |
| Nov | — | 3" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Lee County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lettuce 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.
Lettuce Planting Timeline — Lee County, IA
Lettuce Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Direct Sow | April 2 | Apr 2 – Apr 23 |
| Harvest | May 21 | May 21 – Jul 30 |
| Fall Sowing | August 9 | Aug 9 – Aug 23 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Only during dry spells
📅 Days to Maturity
30–60 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
185 days in Lee County
Growing Tips for Lettuce in Lee County
Direct sow Lettuce outdoors after April 16 in Lee County when soil has warmed and frost danger has passed.
Your generous 185.0-day season in Lee County allows multiple plantings of Lettuce. Sow every 15.0 days for continuous harvest.
Common pests for Lettuce in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Sow seeds directly every 2 weeks for continuous harvest. Provide afternoon shade in warm weather to delay bolting. Harvest in the morning for crispest leaves.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Very easy to save. Let a few plants bolt each season.
Lettuce in Other Locations
Frequently Asked Questions
When should I plant Lettuce in Lee County, IA?
Lee County is in Zone 5b with an average last frost of April 16. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lee County, IA?
Lee County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 16 and first fall frost is October 18.
Plan Your Garden with Confidence
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