When to Plant Butternut Squash in Lassen County, CA
Butternut squash is a popular winter squash with a long neck, small seed cavity, and sweet, nutty orange flesh. It stores exceptionally well for months.
Lassen County, California is in USDA Zone 6b. The average last spring frost is May 28 and the first fall frost is September 29, giving you a growing season of approximately 124 days.
At an elevation of 1,854 feet, Lassen County receives approximately 43.7 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Butternut Squash to ensure they mature before fall.
Lassen County Soil Profile
Soil Type
Loam
Soil pH
6.1-7.5
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 Lassen County
How your county's soil matches Butternut Squash's growing requirements.
Soil pH
Your soil pH (6.1–7.5) overlaps with Butternut Squash's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Lassen County is excellent for Butternut Squash — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Butternut Squash.
How to Plant Butternut Squash
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Butternut Squash
Butternut Squash needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.
| Month | Butternut Squash Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 9.2" | 0" | ❄️ Dormant |
| Feb | — | 9.8" | 0" | ❄️ Dormant |
| Mar | — | 7.7" | 0" | ❄️ Dormant |
| Apr | — | 3.2" | 0" | ❄️ Dormant |
| May | 4.8" | 1" | 3.8" | 🚿 Regular watering |
| Jun | 4.8" | 0.2" | 4.6" | 🚿 Regular watering |
| Jul | 4.8" | 0" | 4.8" | 🚿 Regular watering |
| Aug | 4.8" | 0" | 4.8" | 🚿 Regular watering |
| Sep | 4.8" | 0.5" | 4.3" | 🚿 Regular watering |
| Oct | — | 1.7" | 0" | ❄️ Dormant |
| Nov | — | 3.9" | 0" | ❄️ Dormant |
| Dec | — | 6.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Lassen County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Butternut Squash 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.
Butternut Squash Planting Timeline — Lassen County, CA
Butternut Squash Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 23 | Apr 23 – May 7 |
| Transplant Outdoors | June 11 | Jun 11 – Jun 25 |
| Direct Sow | June 4 | Jun 4 – Jun 25 |
| Harvest | September 10 | Sep 10 – Oct 15 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | — |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.1"/week · Natural rainfall sufficient
📅 Days to Maturity
85–110 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
124 days in Lassen County
Growing Tips for Butternut Squash in Lassen County
Direct sow Butternut Squash outdoors after May 28 in Lassen County when soil has warmed and frost danger has passed.
Common pests for Butternut Squash in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 3 weeks early or direct sow after frost. Allow 6-8 feet for sprawling vines. Harvest when the skin is hard and uniformly tan. Cure in the sun for 10 days.
Companion Planting
Good Companions
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Check more plant combinations with our Companion Planting Checker →
Butternut Squash in Other Locations
Frequently Asked Questions
When should I plant Butternut Squash in Lassen County, CA?
Lassen County is in Zone 6b with an average last frost of May 28. Plan your Butternut Squash planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lassen County, CA?
Lassen County, California is in USDA Hardiness Zone 6b. The average last spring frost is May 28 and first fall frost is September 29.
Plan Your Garden with Confidence
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