When to Plant Celtuce in Knox County, IN
Knox County, Indiana gardeners: here's your May plan
May is a pivotal month for Knox County, Indiana gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Sow celtuce in trays indoors
Your window is short. These crops want several weeks of indoor growth before they go outside.
Coming up in June — start thinking about
- First harvests: celtuce
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.
Knox County, Indiana is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 23, giving you a growing season of approximately 196 days.
At an elevation of 735 feet, Knox County receives approximately 38.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Celtuce during the growing season.
Knox County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.2
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 Knox County
How your county's soil matches Celtuce's growing requirements.
Soil pH
Your soil pH (6.0–7.2) overlaps with Celtuce's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Knox County is excellent for Celtuce — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.9%). Annual compost additions will help Celtuce.
How to Plant Celtuce
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Celtuce
Sow every 6.9 weeks. Last sowing by Jul 25 to harvest before frost.
For a dedicated fall crop, sow by Aug 14.
Plant Water Budget
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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| May | 3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4.2" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 2.7" | 0.3" | 💧 Light watering |
| Nov | — | 3.1" | 0" | ❄️ Dormant |
| Dec | — | 2.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Knox 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 Planting Timeline — Knox County, IN
Celtuce Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | April 10 | Apr 10 – Apr 24 |
| Direct Sow | March 27 | Mar 27 – Apr 17 |
| Harvest | June 12 | Jun 12 – Jul 24 |
| Fall Sowing | August 14 | Aug 14 – Aug 28 |
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 | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
196 days in Knox County
Growing Tips for Celtuce in Knox County
Direct sow Celtuce outdoors after April 10 in Knox 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 →
Celtuce in Other Locations
Frequently Asked Questions
When should I plant Celtuce in Knox County, IN?
Knox County is in Zone 6b with an average last frost of April 10. Plan your Celtuce planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, IN?
Knox County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 23.
Your Knox County Garden Planner — Free
A 24-page printable planner built for Knox County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.