When to plant Lettuce in Harper County, KS
For Lettuce in Harper County, the safe spring window opens around March 26 and closes around April 16. Last expected frost is April 9, first fall frost October 27, giving a 201-day growing season. A second sowing from August 18 to September 1 extends the harvest into fall.
When to Plant Lettuce in Harper County, KS
Your July gardening checklist
Each item below is timed to Harper County, Kansas's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Pick lettuce
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Looking ahead to August
- Fall sowing: lettuce
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.
Harper County, Kansas is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 27, giving you a growing season of approximately 201 days.
At an elevation of 745 feet, Harper County receives approximately 27.7 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Lettuce during the growing season.
Harper County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
Drainage
Well Drained
Lettuce 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 Harper County
How your county's soil matches Lettuce's growing requirements.
Soil pH
Your soil pH (6.2–7.8) overlaps with Lettuce's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Harper 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 (4.1%) — 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 28 to harvest before frost.
For a dedicated fall crop, sow by Aug 18.
Lettuce Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | 3" | 2.6" | 0.4" | 💧 Light watering |
| May | 3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 2.7" | 0.3" | 💧 Light watering |
| Oct | 3" | 1.9" | 1.1" | 💧 Light watering |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Harper 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 — Harper County, KS
Lettuce Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 5 | Mar 5 – Mar 19 |
| Transplant Outdoors | April 9 | Apr 9 – Apr 23 |
| Direct Sow | March 26 | Mar 26 – Apr 16 |
| Harvest | May 14 | May 14 – Jul 23 |
| Fall Sowing | August 18 | Aug 18 – Sep 1 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · 1-2 times/week
📅 Days to Maturity
30–60 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
201 days in Harper County
Growing Tips for Lettuce in Harper County
Direct sow Lettuce outdoors after April 09 in Harper County when soil has warmed and frost danger has passed.
Your generous 201.0-day season in Harper 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.
Recommended Lettuce Varieties for Harper County
Bolt-resistant varieties for warm summers — grow as spring/fall crop
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 Harper County, KS?
Harper County is in Zone 7a with an average last frost of April 9. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harper County, KS?
Harper County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 27.
When should I plant Lettuce in Harper County, KS?
In Harper County, KS, plant Lettuce after the last frost (around April 9) and before the first frost (around October 27). Best results when soil holds above 50°F.
What growing zone is Harper County, KS for Lettuce?
Harper County sits in USDA Zone 7a. Lettuce grows reliably in zones 2a through 11b, so it's a good fit here.
Can Lettuce grow in Harper County's climate?
Yes — Lettuce grows well in Harper County's temperate climate. Harper County averages a 201-day frost-free season, with last frost around April 9 and first frost around October 27.
Your Harper County Garden Planner — Free
A 22-page printable planner built for Harper County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.