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When to Plant Celtuce in Harper County, KS

Harper County, Kansas Zone 7a May

This month in Harper County, Kansas

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 9
Avg. first frost October 27
Soil temp (4") 64°F
Watering Low
Pest pressure Low
Daylight 14 hrs
  1. Begin indoor sowing: celtuce

    Your window is short. These crops want several weeks of indoor growth before they go outside.

To set up a strong June, finish these tasks
  • First harvests: celtuce

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Celtuce (stem lettuce) is a Chinese vegetable grown for its thick, crunchy stem rather than its leaves. The peeled stem has a mild, cucumber-like flavor.

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 Celtuce during the growing season.

Harper County, KS (Zone 7a) Long season
201 days
Last Spring Frost April 9
201 growing days
First Fall Frost October 27

Harper County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (98 days to spare)
Start indoors: Feb 27 Transplant: Apr 3 🍅 Harvest: Jun 5 – Jul 17
Recommended (50%) ✓ Fits season (96 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: Jun 11 – Jul 23
Safe Start (90%) ✓ Fits season (99 days to spare)
Start indoors: Mar 18 Transplant: Apr 22 🍅 Harvest: Jun 24 – Aug 5

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 Celtuce's growing requirements.

Soil pH

Your soil pH (6.2–7.8) overlaps with Celtuce's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Harper County is excellent for Celtuce — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Celtuce.

Organic Matter

Organic matter is excellent (4.1%) — Celtuce will thrive.

How to Plant Celtuce

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Celtuce

3
successive plantings in your 201-day season

Sow every 6.9 weeks. Last sowing by Jul 29 to harvest before frost.

For a dedicated fall crop, sow by Aug 18.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.6″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 711 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Celtuce

Celtuce needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Celtuce 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.

Celtuce 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.

Celtuce needs ~1,200 GDD — county provides 3,216 GDD Excellent fit

Celtuce Planting Timeline — Harper County, KS

Celtuce 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 June 11 Jun 11 – Jul 23
Fall Sowing August 18 Aug 18 – Sep 1

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May
June Harvest
July Harvest
August Fall Sowing
September Fall Sowing
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · 1-2 times/week

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

201 days in Harper County

Growing Tips for Celtuce in Harper County

Direct sow Celtuce outdoors after April 09 in Harper County when soil has warmed and frost danger has passed.

Common pests for Celtuce in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or start indoors. Space 12 inches apart. Harvest when stems are about 1 inch in diameter. Peel the tough outer skin to reveal the tender center.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celtuce in Harper County, KS?

Harper County is in Zone 7a with an average last frost of April 9. Plan your Celtuce 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.

🌱

Your Harper County Garden Planner — Free

A 24-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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Harper County, KS. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.