Blog

When to Plant Turnip in Kenai Peninsula Borough, AK

Kenai Peninsula Borough, Alaska Zone 5a May

Your May gardening checklist

Here's what deserves your attention in Kenai Peninsula Borough, Alaska this month. Everything below is tailored to Zone 5a and timed around your local frost dates.

Avg. last frost May 17
Avg. first frost September 25
Soil temp (4") 52°F
Watering High
Pest pressure Low
Daylight 16.8 hrs
  1. Seed turnip outdoors

    Thin ruthlessly once seedlings are up. Crowded roots mean smaller crops from every plant.

Looking ahead to June
  • First harvests: turnip

Instant PDF download. No spam, unsubscribe any time.

Turnips are a fast-growing cool-season root vegetable with edible roots and greens. Baby turnips are sweet and tender while mature ones are more pungent.

Kenai Peninsula Borough, Alaska is in USDA Zone 5a. The average last spring frost is May 17 and the first fall frost is September 25, giving you a growing season of approximately 131 days.

At an elevation of 1,824 feet, Kenai Peninsula Borough receives approximately 55.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 60°F, so choose short-season varieties of Turnip to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Turnip root diseases.

Kenai Peninsula Borough, AK (Zone 5a) Short season
131 days
Last Spring Frost May 17
131 growing days
First Fall Frost September 25
Share this guide:

Kenai Peninsula Borough Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (52 days to spare)
Transplant: May 12 🍅 Harvest: Jun 23 – Jul 28
Recommended (50%) ✓ Fits season (54 days to spare)
Transplant: May 17 🍅 Harvest: Jun 28 – Aug 2
Safe Start (90%) ✓ Fits season (54 days to spare)
Transplant: Jun 1 🍅 Harvest: Jul 13 – Aug 17

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 Kenai Peninsula Borough

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

Soil pH

Your soil pH (5.2–6.8) overlaps with Turnip's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Kenai Peninsula Borough is excellent for Turnip — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (6.6%) — Turnip will thrive.

How to Plant Turnip

0.5"
Planting Depth
4"
Between Plants
12"
Between Rows

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

Succession Planting Turnip

3
successive plantings in your 131-day season

Sow every 4.6 weeks. Last sowing by Jul 27 to harvest before frost.

For a dedicated fall crop, sow by Jul 17.

Plant Water Budget

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

Monthly Watering Guide for Turnip

Turnip needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Turnip Needs Rainfall You Supplement Action
Jan 3.2" 0" ❄️ Dormant
Feb 2.4" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 4.3" 2.3" 2" 💧 Light watering
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 7.6" 0" ✅ Rainfall sufficient
Aug 4.3" 8.3" 0" ✅ Rainfall sufficient
Sep 4.3" 10.1" 0" ✅ Rainfall sufficient
Oct 7" 0" ❄️ Dormant
Nov 4.3" 0" ❄️ Dormant
Dec 3.2" 0" ❄️ Dormant

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

Turnip 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.

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

Turnip Planting Timeline — Kenai Peninsula Borough, AK

Turnip Planting Calendar

Activity When Date Range
Direct Sow May 3 May 3 – May 24
Harvest June 14 Jun 14 – Jul 19
Fall Sowing July 17 Jul 17 – Jul 31

Plant 0.5" deep · 4" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Direct Sow
June Harvest
July Fall Sowing Harvest
August
September
October
November
December
Share this guide:

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

131 days in Kenai Peninsula Borough

Growing Tips for Turnip in Kenai Peninsula Borough

Direct sow Turnip outdoors after May 17 in Kenai Peninsula Borough when soil has warmed and frost danger has passed.

Common pests for Turnip in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in early spring or late summer. Harvest when roots are 2-3 inches in diameter for best flavor. Both the roots and the greens are nutritious and edible.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Turnip in Kenai Peninsula Borough, AK?

Kenai Peninsula Borough is in Zone 5a with an average last frost of May 17. Plan your Turnip planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kenai Peninsula Borough, AK?

Kenai Peninsula Borough, Alaska is in USDA Hardiness Zone 5a. The average last spring frost is May 17 and first fall frost is September 25.

🌱

Your Kenai Peninsula Borough Garden Planner — Free

A 24-page printable planner built for Kenai Peninsula Borough (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Kenai Peninsula Borough, 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.