Blog

When to Plant Cress in Kenai Peninsula Borough, AK

Kenai Peninsula Borough, Alaska Zone 5a May

Your May planting checklist for Kenai Peninsula Borough, Alaska

Your Kenai Peninsula Borough, Alaska garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

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. Get cress in the ground

    Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.

  2. Scatter cress into prepared beds

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

  3. Pick cress

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

To set up a strong June, finish these tasks
  • Starting indoors: cress
  • First harvests: cress

Instant PDF download. No spam, unsubscribe any time.

Garden cress is one of the fastest-growing edibles, producing peppery sprouts in as little as two weeks. It is excellent for microgreens and garnishes.

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 Cress to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cress 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 (94 days to spare)
Start indoors: Apr 7 Transplant: May 12 🍅 Harvest: May 26 – Jun 16
Recommended (50%) ✓ Fits season (96 days to spare)
Start indoors: Apr 12 Transplant: May 17 🍅 Harvest: May 31 – Jun 21
Safe Start (90%) ✓ Fits season (96 days to spare)
Start indoors: Apr 27 Transplant: Jun 1 🍅 Harvest: Jun 15 – Jul 6

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 Cress's growing requirements.

Soil pH

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

Soil Texture

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

Organic Matter

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

How to Plant Cress

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

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

Succession Planting Cress

11
successive plantings in your 131-day season

Sow every 1.6 weeks. Last sowing by Sep 04 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 Cress

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

Month Cress 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.

Cress 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.

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

Cress Planting Timeline — Kenai Peninsula Borough, AK

Cress Planting Calendar

Activity When Date Range
Start Indoors April 12 Apr 12 – Apr 26
Transplant Outdoors May 17 May 17 – May 31
Direct Sow May 3 May 3 – May 24
Harvest May 31 May 31 – Jun 21
Fall Sowing July 17 Jul 17 – Jul 31

Plant 0.5" deep · 2" apart · Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

14–21 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

131 days in Kenai Peninsula Borough

Growing Tips for Cress in Kenai Peninsula Borough

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

Your generous 131.0-day season in Kenai Peninsula Borough allows multiple plantings of Cress. Sow every 7.0 days for continuous harvest.

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

General growing tips

Sow seeds thickly on moist soil or paper towels. Keep moist and harvest when 2-3 inches tall. Succession sow every few days for continuous supply. Grows well indoors year-round.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

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

Kenai Peninsula Borough is in Zone 5a with an average last frost of May 17. Plan your Cress 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.