When to Plant Lettuce in Summit County, UT
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.
Summit County, Utah is in USDA Zone 5a. The average last spring frost is June 10 and the first fall frost is September 12, giving you a growing season of approximately 94 days.
At an elevation of 8,145 feet, Summit County receives approximately 24.8 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Lettuce during the growing season.
Summit County Soil Profile
Soil Type
Loam
Soil pH
6.4-8.3
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 Summit County
How your county's soil matches Lettuce's growing requirements.
Soil pH
Your soil pH (6.4–8.3) is more alkaline than Lettuce prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Summit County is excellent for Lettuce — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Lettuce.
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 Jul 14 to harvest before frost.
For a dedicated fall crop, sow by Jul 04.
Plant 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 | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | — | 2.9" | 0" | ❄️ Dormant |
| Jun | 3" | 1.8" | 1.2" | 💧 Light watering |
| Jul | 3" | 1.9" | 1.1" | 💧 Light watering |
| Aug | 3" | 2.5" | 0.5" | 💧 Light watering |
| Sep | 3" | 2" | 1" | 💧 Light watering |
| Oct | — | 2.1" | 0" | ❄️ Dormant |
| Nov | — | 2" | 0" | ❄️ Dormant |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Summit 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 — Summit County, UT
Lettuce Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 6 | May 6 – May 20 |
| Transplant Outdoors | June 10 | Jun 10 – Jun 24 |
| Direct Sow | May 27 | May 27 – Jun 17 |
| Harvest | July 15 | Jul 15 – Sep 23 |
| Fall Sowing | July 4 | Jul 4 – Jul 18 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| 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 5a
📆 Growing Season
94 days in Summit County
Growing Tips for Lettuce in Summit County
Direct sow Lettuce outdoors after June 10 in Summit 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 Summit County
Bolt-resistant varieties for warm summers — grow as spring/fall crop
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 Summit County, UT?
Summit County is in Zone 5a with an average last frost of June 10. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.
What planting zone is Summit County, UT?
Summit County, Utah is in USDA Hardiness Zone 5a. The average last spring frost is June 10 and first fall frost is September 12.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Summit County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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