When to Plant Hardy Kiwi in Phillips County, MT
Your May gardening checklist
May is a pivotal month for Phillips County, Montana gardens. Focus on these tasks first and you'll set up the rest of the season for success.
Before June arrives, get these ready
- 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.
Phillips County, Montana is in USDA Zone 3b. The average last spring frost is May 18 and the first fall frost is September 21, giving you a growing season of approximately 126 days.
At an elevation of 6,886 feet, Phillips County receives approximately 19 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Hardy Kiwi to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Hardy Kiwi successfully. Mulch heavily to conserve soil moisture.
Phillips County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.6
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 Phillips County
How your county's soil matches Hardy Kiwi's growing requirements.
Soil pH
Your soil pH (6.7–7.6) is more alkaline than Hardy Kiwi prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Phillips County is excellent for Hardy Kiwi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). 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" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | — | 1.9" | 0" | ❄️ Dormant |
| May | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Jun | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Jul | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Aug | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Sep | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Oct | — | 1.8" | 0" | ❄️ Dormant |
| Nov | — | 1.3" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Phillips 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 — Phillips County, MT
Hardy Kiwi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 15 | Jun 15 – Jun 29 |
· 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: too_alkaline
🗺️ USDA Zone
Zone 3b
📆 Growing Season
126 days in Phillips County
Growing Tips for Hardy Kiwi in Phillips County
Direct sow Hardy Kiwi outdoors after May 18 in Phillips County when soil has warmed and frost danger has passed.
Your 126.0-day growing season in Phillips County is tight for Hardy Kiwi (1095.0-1825.0 days to maturity). Start indoors and choose early-maturing varieties.
Phillips County receives only 19" 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 Phillips County, MT?
Phillips County is in Zone 3b with an average last frost of May 18. Plan your Hardy Kiwi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Phillips County, MT?
Phillips County, Montana is in USDA Hardiness Zone 3b. The average last spring frost is May 18 and first fall frost is September 21.
Your Phillips County Garden Planner — Free
A 24-page printable planner built for Phillips County (Zone 3b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.