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When to Plant Tomatoes in Bethel Census Area, AK

Bethel Census Area, Alaska Zone 4a May

Your May gardening checklist

Here's what deserves your attention in Bethel Census Area, Alaska this month. Everything below is tailored to Zone 4a and timed around your local frost dates.

Avg. last frost May 22
Avg. first frost September 21
Soil temp (4") 45°F
Watering High
Pest pressure Low
Daylight 17 hrs
Before June arrives, get these ready
  • Transplants going out: tomatoes
  • Direct-sowing: tomatoes

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Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.

Bethel Census Area, Alaska is in USDA Zone 4a. The average last spring frost is May 22 and the first fall frost is September 21, giving you a growing season of approximately 122 days.

At an elevation of 1,369 feet, Bethel Census Area receives approximately 50.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 70°F, so choose short-season varieties of Tomatoes to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Tomatoes root diseases.

Bethel Census Area, AK (Zone 4a) Short season
122 days
Last Spring Frost May 22
122 growing days
First Fall Frost September 21

Bethel Census Area Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 14 Transplant: Jun 6 🍅 Harvest: Aug 8 – Oct 17
Recommended (50%) ✗ May not fit
Start indoors: Mar 20 Transplant: Jun 12 🍅 Harvest: Aug 14 – Oct 23
Safe Start (90%) ✗ May not fit
Start indoors: Apr 1 Transplant: Jun 24 🍅 Harvest: Aug 26 – Nov 4

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 Bethel Census Area

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

Soil pH

Your soil pH (5.2–6.3) is more acidic than Tomatoes prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Bethel Census Area is excellent for Tomatoes — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Tomatoes.

Organic Matter

Organic matter is excellent (5.8%) — Tomatoes will thrive.

How to Plant Tomatoes

0.5"
Planting Depth
24"
Between Plants
36"
Between Rows

Succession Planting Tomatoes

2
successive plantings in your 122-day season

Sow every 6.9 weeks. Last sowing by Jun 28 to harvest before frost.

Plant Water Budget

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

Monthly Watering Guide for Tomatoes

Tomatoes needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.

Month Tomatoes Needs Rainfall You Supplement Action
Jan 2.6" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 1.4" 0" ❄️ Dormant
May 5.2" 1.8" 3.4" 🚿 Regular watering
Jun 5.2" 4" 1.2" 💧 Light watering
Jul 5.2" 6.3" 0" ✅ Rainfall sufficient
Aug 5.2" 7.6" 0" ✅ Rainfall sufficient
Sep 5.2" 9.4" 0" ✅ Rainfall sufficient
Oct 6.7" 0" ❄️ Dormant
Nov 4.1" 0" ❄️ Dormant
Dec 2.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Bethel Census Area). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Tomatoes 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.

Tomatoes needs ~181 GDD — county provides 305 GDD Excellent fit

Tomatoes Planting Timeline — Bethel Census Area, AK

Tomatoes Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 – Apr 3
Transplant Outdoors June 12 Jun 12 – Jun 26
Direct Sow June 5 Jun 5 – Jun 26
Harvest August 14 Aug 14 – Oct 23

Plant 0.5" deep · 24" apart · Rows 36" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.2"/week · Natural rainfall sufficient

📅 Days to Maturity

60–85 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 4a

📆 Growing Season

122 days in Bethel Census Area

Growing Tips for Tomatoes in Bethel Census Area

Direct sow Tomatoes outdoors after May 22 in Bethel Census Area when soil has warmed and frost danger has passed.

Common pests for Tomatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.

Recommended Tomatoes Varieties for Bethel Census Area

Choose determinate, early-maturing varieties for your short season

Early Girl (52d) Stupice (55d) Glacier (55d) Sub Arctic Plenty (45d)

Disease-resistant varieties for your humid climate

Mountain Merit (VF) Defiant (LB) Iron Lady (EB/LB/SF)

Companion Planting

Good Companions

Avoid Planting Near

  • Cabbage
  • Fennel
  • Potatoes

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Tomatoes Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Scoop seeds from ripe fruit; ferment 2-3 days to remove gel coating.
Storage Store airtight; viable 4-6 years at 35°F, under 45% humidity.

Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.

Frequently Asked Questions

When should I plant Tomatoes in Bethel Census Area, AK?

Bethel Census Area is in Zone 4a with an average last frost of May 22. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.

What planting zone is Bethel Census Area, AK?

Bethel Census Area, Alaska is in USDA Hardiness Zone 4a. The average last spring frost is May 22 and first fall frost is September 21.

🌱

Your Bethel Census Area Garden Planner — Free

A 24-page printable planner built for Bethel Census Area (Zone 4a). 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 Bethel Census Area, AK. Local conditions may vary. Last updated: May 2026.

Sources & credits

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