When to Plant Lettuce in Washington County, UT
What to do in May
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Washington County, Utah.
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Time to start lettuce inside
Your window is short. These crops want several weeks of indoor growth before they go outside.
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It's harvest week for lettuce
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Coming up in June — start thinking about
- 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.
Washington County, Utah is in USDA Zone 8b. The average last spring frost is April 6 and the first fall frost is November 1, giving you a growing season of approximately 209 days.
At an elevation of 3,524 feet, Washington County receives approximately 12.7 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Lettuce during the growing season. With low rainfall, drip irrigation is essential for growing Lettuce successfully. Mulch heavily to conserve soil moisture.
Washington County Soil Profile
Soil Type
Loam
Soil pH
6.7-8
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 Washington County
How your county's soil matches Lettuce's growing requirements.
Soil pH
Your soil pH (6.7–8.0) is more alkaline than Lettuce prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Washington County is excellent for Lettuce — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Lettuce.
Organic Matter
Organic matter is moderate (2.4%). 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 Sep 02 to harvest before frost.
For a dedicated fall crop, sow by Aug 23.
Plant Water Budget
Water stress score is 10/10 — 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" | 0" | ❄️ Dormant |
| Feb | — | 0.6" | 0" | ❄️ Dormant |
| Mar | — | 1.1" | 0" | ❄️ Dormant |
| Apr | 3" | 1.2" | 1.8" | 🚿 Regular watering |
| May | 3" | 1.4" | 1.6" | 🚿 Regular watering |
| Jun | 3" | 0.9" | 2.1" | 🚿 Regular watering |
| Jul | 3" | 1.2" | 1.8" | 🚿 Regular watering |
| Aug | 3" | 1.4" | 1.6" | 🚿 Regular watering |
| Sep | 3" | 0.9" | 2.1" | 🚿 Regular watering |
| Oct | 3" | 1.2" | 1.8" | 🚿 Regular watering |
| Nov | 3" | 1" | 2" | 🚿 Regular watering |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Washington 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 — Washington County, UT
Lettuce Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 2 | Mar 2 – Mar 16 |
| Transplant Outdoors | April 6 | Apr 6 – Apr 20 |
| Direct Sow | March 23 | Mar 23 – Apr 13 |
| Harvest | May 11 | May 11 – Jul 20 |
| Fall Sowing | August 23 | Aug 23 – Sep 6 |
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 · 2-3 times/week
📅 Days to Maturity
30–60 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 8b
📆 Growing Season
209 days in Washington County
Growing Tips for Lettuce in Washington County
Direct sow Lettuce outdoors after April 06 in Washington County when soil has warmed and frost danger has passed.
Your generous 209.0-day season in Washington 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 Washington 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 Washington County, UT?
Washington County is in Zone 8b with an average last frost of April 6. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, UT?
Washington County, Utah is in USDA Hardiness Zone 8b. The average last spring frost is April 6 and first fall frost is November 1.
Your Washington County Garden Planner — Free
A 24-page printable planner built for Washington County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.