When to plant Lettuce in Lewis and Clark County County,
In Lewis and Clark County County, plant Lettuce in spring between May 22 and June 12, once soil temps hold above 50°F. Lewis and Clark County County's last frost averages May 29, so be cautious and check the 10-day forecast before planting tender crops. For a fall crop, sow between June 26 and July 10 — roughly 60 days before the first frost on September 18.
When to Plant Lettuce in Lewis and Clark County, MT
June to-do list for Lewis and Clark County, Montana
We've pulled the most time-sensitive tasks for Lewis and Clark County, Montana this June and put them front and centre. Tackle them in order.
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Plant your fall garden: lettuce
Count back from your first frost (September 18) — these need to mature before the cold arrives.
A few tasks this June that'll pay off in July
- Starting indoors: lettuce
- First harvests: 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.
Lewis and Clark County, Montana is in USDA Zone 4b. The average last spring frost is May 29 and the first fall frost is September 18, giving you a growing season of approximately 112 days.
At an elevation of 7,064 feet, Lewis and Clark County receives approximately 22.2 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Lettuce to ensure they mature before fall.
Lewis and Clark County Soil Profile
Soil Type
Loam
Soil pH
6.5-8.1
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 Lewis and Clark County
How your county's soil matches Lettuce's growing requirements.
Soil pH
Your soil pH (6.5–8.1) is more alkaline than Lettuce prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Lewis and Clark County is excellent for Lettuce — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Lettuce.
How to Plant Lettuce
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Lettuce
Sow every 3.4 weeks. Last sowing by Jul 20 to harvest before frost.
For a dedicated fall crop, sow by Jun 26.
Lettuce Water Budget
Water stress score is 8/10 — 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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | — | 2.3" | 0" | ❄️ Dormant |
| May | 3" | 2.6" | 0.4" | 💧 Light watering |
| Jun | 3" | 1.5" | 1.5" | 🚿 Regular watering |
| Jul | 3" | 1.9" | 1.1" | 💧 Light watering |
| Aug | 3" | 2.3" | 0.7" | 💧 Light watering |
| Sep | 3" | 1.8" | 1.2" | 💧 Light watering |
| Oct | — | 1.7" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Lewis and Clark 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 — Lewis and Clark County, MT
Lettuce Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 17 | Apr 17 – May 1 |
| Transplant Outdoors | May 29 | May 29 – Jun 12 |
| Direct Sow | May 22 | May 22 – Jun 12 |
| Harvest | July 3 | Jul 3 – Sep 11 |
| Fall Sowing | June 26 | Jun 26 – Jul 10 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
30–60 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 4b
📆 Growing Season
112 days in Lewis and Clark County
Growing Tips for Lettuce in Lewis and Clark County
Direct sow Lettuce outdoors after May 29 in Lewis and Clark County when soil has warmed and frost danger has passed.
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 Lewis and Clark County
Fast-maturing leaf and butterhead types
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 Lewis and Clark County, MT?
Lewis and Clark County is in Zone 4b with an average last frost of May 29. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lewis and Clark County, MT?
Lewis and Clark County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 29 and first fall frost is September 18.
When should I plant Lettuce in Lewis and Clark County County, ?
In Lewis and Clark County County, , plant Lettuce after the last frost (around May 29) and before the first frost (around September 18). Best results when soil holds above 50°F.
What growing zone is Lewis and Clark County County, for Lettuce?
Lewis and Clark County County sits in USDA Zone 4b. Lettuce grows reliably in zones 2a through 11b, so it's a good fit here.
Can Lettuce grow in Lewis and Clark County County's climate?
Yes — Lettuce grows well in Lewis and Clark County County's temperate climate. Lewis and Clark County County averages a 112-day frost-free season, with last frost around May 29 and first frost around September 18.
Your Lewis and Clark County Garden Planner — Free
A 22-page printable planner built for Lewis and Clark County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.