When to Plant Cranberries in Fairbanks North Star Borough, AK
What to do in May
Your garden in Fairbanks North Star Borough, Alaska is working on a schedule, even when you're not. Here's where you should be this May.
June will be here before you know it — start on
- Transplants going out: cranberries
Cranberries are low-growing, vine-like shrubs that produce tart red berries in fall. They grow in acidic, boggy conditions and are surprisingly easy to cultivate.
Fairbanks North Star Borough, Alaska is in USDA Zone 3b. The average last spring frost is May 15 and the first fall frost is September 8, giving you a growing season of approximately 116 days.
At an elevation of 2,540 feet, Fairbanks North Star Borough receives approximately 29.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 69°F, so choose short-season varieties of Cranberries to ensure they mature before fall.
Fairbanks North Star Borough Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.4
Drainage
Well Drained
Plant Planting Risk Windows
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 Fairbanks North Star Borough
How your county's soil matches Cranberries's growing requirements.
Soil pH
Your soil pH (5.2–6.4) is more alkaline than Cranberries prefers (4.0–5.5). Add sulfur or peat moss to lower pH.
Soil Texture
The silt loam soil in Fairbanks North Star Borough is excellent for Cranberries — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Cranberries.
Organic Matter
Organic matter is excellent (6.7%) — Cranberries will thrive.
How to Plant Cranberries
Plant Water Budget
Monthly Watering Guide for Cranberries
Cranberries needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Cranberries Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 1" | 0" | ❄️ Dormant |
| Apr | — | 1" | 0" | ❄️ Dormant |
| May | 6.5" | 1.2" | 5.3" | 🚿 Regular watering |
| Jun | 6.5" | 2.4" | 4.1" | 🚿 Regular watering |
| Jul | 6.5" | 3.3" | 3.2" | 💧 Light watering |
| Aug | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Sep | 6.5" | 5.3" | 1.2" | 💧 Light watering |
| Oct | — | 3.8" | 0" | ❄️ Dormant |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Fairbanks North Star Borough). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cranberries 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.
Cranberries Planting Timeline — Fairbanks North Star Borough, AK
Cranberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 12 | Jun 12 – Jun 26 |
· 36" apart · Rows 48" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Transplant Outdoors |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · Natural rainfall sufficient
📅 Days to Maturity
730–1095 days
🧪 Soil pH
Needs 4–5.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 3b
📆 Growing Season
116 days in Fairbanks North Star Borough
Growing Tips for Cranberries in Fairbanks North Star Borough
Direct sow Cranberries outdoors after May 15 in Fairbanks North Star Borough when soil has warmed and frost danger has passed.
Your 116.0-day growing season in Fairbanks North Star Borough is tight for Cranberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
Create an acidic, consistently moist bed with peat moss. Cranberries do not need to be flooded to grow; flooding is only used for commercial harvesting. Mulch with sand in early spring.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Cranberries in Other Locations
Frequently Asked Questions
When should I plant Cranberries in Fairbanks North Star Borough, AK?
Fairbanks North Star Borough is in Zone 3b with an average last frost of May 15. Plan your Cranberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is Fairbanks North Star Borough, AK?
Fairbanks North Star Borough, Alaska is in USDA Hardiness Zone 3b. The average last spring frost is May 15 and first fall frost is September 8.
Your Fairbanks North Star Borough Garden Planner — Free
A 24-page printable planner built for Fairbanks North Star Borough (Zone 3b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.