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When to plant Spinach in Juneau City and Borough County,

Juneau City and Borough County's spring Spinach window runs April 19 through May 10. most warm-season crops establish quickly once soil holds above 60°F. A second sowing from July 24 to August 7 extends the harvest into fall.

When to Plant Spinach in Juneau City and Borough, AK

Spinach
Juneau City and Borough, Alaska Zone 7a June

June in Juneau City and Borough, Alaska — your action list

June is a pivotal month for Juneau City and Borough, Alaska gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 3
Avg. first frost October 2
Soil temp (4") 76°F
Watering Moderate
Pest pressure High
Daylight 17.9 hrs
  1. Start spinach indoors

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Pick spinach

    If you can't use it all right away, check the food-preservation section of your planner.

Get ahead of July
  • First harvests: spinach
  • Fall sowing: spinach

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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.

Juneau City and Borough, Alaska is in USDA Zone 7a. The average last spring frost is May 3 and the first fall frost is October 2, giving you a growing season of approximately 152 days.

At an elevation of 930 feet, Juneau City and Borough receives approximately 35.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 57°F, so choose short-season varieties of Spinach to ensure they mature before fall.

Juneau City and Borough, AK (Zone 7a) Moderate season
152 days
Last Spring Frost May 3
152 growing days
First Fall Frost October 2

Juneau City and Borough Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.5

Drainage

Well Drained

Spinach Planting Risk Windows

Early Start (70% safe) ✓ Fits season (59 days to spare)
Start indoors: Mar 23 Transplant: Apr 27 🍅 Harvest: Jun 1 – Aug 3
Recommended (50%) ✓ Fits season (54 days to spare)
Start indoors: Mar 29 Transplant: May 3 🍅 Harvest: Jun 7 – Aug 9
Safe Start (90%) ✓ Fits season (61 days to spare)
Start indoors: Apr 12 Transplant: May 17 🍅 Harvest: Jun 21 – Aug 23

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 Juneau City and Borough

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

Soil pH

Your soil pH (5.1–6.5) is more acidic than Spinach prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Juneau City and Borough is excellent for Spinach — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (6.7%) — Spinach will thrive.

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

5
successive plantings in your 152-day season

Sow every 4 weeks. Last sowing by Aug 13 to harvest before frost.

For a dedicated fall crop, sow by Jul 24.

Spinach Water Budget

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

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 2" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 1" 0" ❄️ Dormant
May 3" 1.6" 1.4" 💧 Light watering
Jun 3" 3.1" 0" ✅ Rainfall sufficient
Jul 3" 4.4" 0" ✅ Rainfall sufficient
Aug 3" 5.3" 0" ✅ Rainfall sufficient
Sep 3" 6.5" 0" ✅ Rainfall sufficient
Oct 3" 4.1" 0" ✅ Rainfall sufficient
Nov 2.7" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Juneau City and Borough). Supplement amounts are based on average rainfall — 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" — 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.

Spinach needs ~0 GDD — county provides 0 GDD May not mature

Spinach Planting Timeline — Juneau City and Borough, AK

Spinach Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 3 May 3 – May 17
Direct Sow April 19 Apr 19 – May 10
Harvest June 7 Jun 7 – Aug 9
Fall Sowing July 24 Jul 24 – Aug 7

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

152 days in Juneau City and Borough

Growing Tips for Spinach in Juneau City and Borough

Direct sow Spinach outdoors after May 03 in Juneau City and Borough when soil has warmed and frost danger has passed.

Your generous 152.0-day season in Juneau City and Borough allows multiple plantings of Spinach. Sow every 17.0 days for continuous harvest.

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 →

🌾 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 35°F, under 45% humidity.

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

Frequently Asked Questions

When should I plant Spinach in Juneau City and Borough, AK?

Juneau City and Borough is in Zone 7a with an average last frost of May 3. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.

What planting zone is Juneau City and Borough, AK?

Juneau City and Borough, Alaska is in USDA Hardiness Zone 7a. The average last spring frost is May 3 and first fall frost is October 2.

When should I plant Spinach in Juneau City and Borough County, ?

In Juneau City and Borough County, , plant Spinach after the last frost (around May 3) and before the first frost (around October 2). Best results when soil holds above 50°F.

What growing zone is Juneau City and Borough County, for Spinach?

Juneau City and Borough County sits in USDA Zone 7a. Spinach grows reliably in zones 2a through 10b, so it's a good fit here.

Can Spinach grow in Juneau City and Borough County's climate?

Yes — Spinach grows well in Juneau City and Borough County's temperate climate. Juneau City and Borough County averages a 152-day frost-free season, with last frost around May 3 and first frost around October 2.

🌱

Your Juneau City and Borough Garden Planner — Free

A 22-page printable planner built for Juneau City and Borough (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Juneau City and Borough, AK. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.