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When to Plant Spinach in Cache County, UT

Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.

Cache County, Utah is in USDA Zone 5b. The average last spring frost is June 11 and the first fall frost is September 2, giving you a growing season of approximately 83 days.

At an elevation of 6,265 feet, Cache County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Spinach to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Spinach successfully. Mulch heavily to conserve soil moisture.

Cache County, UT (Zone 5b) Very short season
83 days
Last Spring Frost June 11
83 growing days
First Fall Frost September 2

Cache County Soil Profile

Soil Type

Loam

Soil pH

6.6-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: Jun 19 – Aug 21
Recommended (50%) ✗ May not fit
Start indoors: May 7 Transplant: Jun 11 🍅 Harvest: Jul 16 – Sep 17
Safe Start (90%) ✓ Fits season (19 days to spare)
Start indoors: May 20 Transplant: Jun 24 🍅 Harvest: Jul 29 – Sep 30

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 Cache County

How your county's soil matches Spinach's growing requirements.

Soil pH

Your soil pH (6.6โ€“8.4) overlaps with Spinach's range (6.5โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Cache County is excellent for Spinach โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Spinach.

How to Plant Spinach

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Spinach

2
successive plantings in your 83-day season

Sow every 4 weeks. Last sowing by Jul 14 to harvest before frost.

For a dedicated fall crop, sow by Jun 24.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Spinach

Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Spinach Needs Rainfall You Supplement Action
Jan โ€” 1.1" 0" โ„๏ธ Dormant
Feb โ€” 0.9" 0" โ„๏ธ Dormant
Mar โ€” 1.3" 0" โ„๏ธ Dormant
Apr โ€” 1.7" 0" โ„๏ธ Dormant
May โ€” 2" 0" โ„๏ธ Dormant
Jun 3" 1.1" 1.9" ๐Ÿšฟ Regular watering
Jul 3" 1.3" 1.7" ๐Ÿšฟ Regular watering
Aug 3" 1.5" 1.5" ๐Ÿšฟ Regular watering
Sep 3" 1.3" 1.7" ๐Ÿšฟ Regular watering
Oct โ€” 1.4" 0" โ„๏ธ Dormant
Nov โ€” 1.1" 0" โ„๏ธ Dormant
Dec โ€” 0.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Cache County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Spinach 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" โ€” every day above 50ยฐF 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.

Spinach needs ~552 GDD — county provides 1,079 GDD Excellent fit

Spinach Planting Timeline โ€” Cache County, UT

Spinach Planting Calendar

Activity When Date Range
Start Indoors May 7 May 7 โ€“ May 21
Transplant Outdoors June 11 Jun 11 โ€“ Jun 25
Direct Sow May 28 May 28 โ€“ Jun 18
Harvest July 16 Jul 16 โ€“ Sep 17
Fall Sowing June 24 Jun 24 โ€“ Jul 8

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Start Indoors Direct Sow
June Transplant Outdoors Direct Sow Fall Sowing
July Fall Sowing Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.7"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6.5โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

83 days in Cache County

Growing Tips for Spinach in Cache County

Direct sow Spinach outdoors after June 11 in Cache County when soil has warmed and frost danger has passed.

General growing tips

Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Spinach Seeds
Life Cycle Annual
Pollination Wind Pollinated
How to Collect Let plants bolt. Harvest seed stalks when seeds turn tan.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Wind pollinated โ€” isolate 1/2 mile for purity. Easy to let bolt in heat.

Frequently Asked Questions

When should I plant Spinach in Cache County, UT?

Cache County is in Zone 5b with an average last frost of June 11. Plan your Spinach planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cache County, UT?

Cache County, Utah is in USDA Hardiness Zone 5b. The average last spring frost is June 11 and first fall frost is September 2.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Cache County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Cache County, UT. Local conditions may vary. Last updated: April 2026.