When to Plant Hardy Kiwi in Big Horn County, MT
May in the garden — Big Horn County, Montana
Each item below is timed to Big Horn County, Montana's frost dates and soil temperatures. Skip nothing, stress about nothing.
A few tasks this May that'll pay off in June
- Transplants going out: hardy kiwi
Hardy kiwi produces grape-sized, smooth-skinned fruits eaten whole without peeling. Unlike fuzzy kiwi, it is extremely cold-hardy to -25F once established.
Big Horn County, Montana is in USDA Zone 5a. The average last spring frost is May 13 and the first fall frost is September 30, giving you a growing season of approximately 140 days.
At an elevation of 5,955 feet, Big Horn County receives approximately 22.5 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Hardy Kiwi to ensure they mature before fall.
Big Horn County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.6
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 Big Horn County
How your county's soil matches Hardy Kiwi's growing requirements.
Soil pH
Your soil pH (6.2–7.6) overlaps with Hardy Kiwi's range (5.5–7.0), though not a perfect match.
Soil Texture
The loam soil in Big Horn County is excellent for Hardy Kiwi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Hardy Kiwi.
How to Plant Hardy Kiwi
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Hardy Kiwi
Hardy Kiwi needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Hardy Kiwi Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | — | 2.4" | 0" | ❄️ Dormant |
| May | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Jun | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jul | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Aug | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Sep | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Oct | — | 2.1" | 0" | ❄️ Dormant |
| Nov | — | 1.5" | 0" | ❄️ Dormant |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Big Horn County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Hardy Kiwi 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.
Hardy Kiwi Planting Timeline — Big Horn County, MT
Hardy Kiwi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 3 | Jun 3 – Jun 17 |
· 72" apart · Rows 96" 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"/week · 1-2 times/week
📅 Days to Maturity
1095–1825 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
140 days in Big Horn County
Growing Tips for Hardy Kiwi in Big Horn County
Direct sow Hardy Kiwi outdoors after May 13 in Big Horn County when soil has warmed and frost danger has passed.
Your 140.0-day growing season in Big Horn County is tight for Hardy Kiwi (1095.0-1825.0 days to maturity). Start indoors and choose early-maturing varieties.
Big Horn County receives only 22" of rain annually. Hardy Kiwi needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Plant male and female vines for pollination. Provide very strong trellising as vines become massive. Prune similarly to grapes. Protect young plants from late spring frost.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Hardy Kiwi in Other Locations
Frequently Asked Questions
When should I plant Hardy Kiwi in Big Horn County, MT?
Big Horn County is in Zone 5a with an average last frost of May 13. Plan your Hardy Kiwi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Big Horn County, MT?
Big Horn County, Montana is in USDA Hardiness Zone 5a. The average last spring frost is May 13 and first fall frost is September 30.
Your Big Horn County Garden Planner — Free
A 24-page printable planner built for Big Horn County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.