When to plant Geraniums in Judith Basin County, MT
Plant Geraniums in Judith Basin County, between May 30 and June 13 — the only viable window. Zone 4b's short season (119 frost-free days) rules out a fall crop.
When to Plant Geraniums in Judith Basin County, MT
June in Judith Basin County, Montana — your action list
Your garden in Judith Basin County, Montana is working on a schedule, even when you're not. Here's where you should be this June.
Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.
Judith Basin County, Montana is in USDA Zone 4b. The average last spring frost is May 23 and the first fall frost is September 19, giving you a growing season of approximately 119 days.
At an elevation of 6,308 feet, Judith Basin County receives approximately 17.7 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Geraniums to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Geraniums successfully. Mulch heavily to conserve soil moisture.
Judith Basin County Soil Profile
Soil Type
Loam
Soil pH
6.5-8.2
Drainage
Well Drained
Geraniums 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 Judith Basin County
How your county's soil matches Geraniums's growing requirements.
Soil pH
Your soil pH (6.5–8.2) is more alkaline than Geraniums prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Judith Basin County is excellent for Geraniums — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Geraniums.
How to Plant Geraniums
Geraniums Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Geraniums
Geraniums needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Geraniums Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.4" | 0" | ❄️ Dormant |
| Apr | — | 1.9" | 0" | ❄️ Dormant |
| May | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Jun | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Jul | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Aug | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Sep | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Oct | — | 1.7" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Judith Basin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Geraniums 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.
Geraniums Planting Timeline — Judith Basin County, MT
Geraniums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 7 | Mar 7 – Mar 21 |
| Transplant Outdoors | May 30 | May 30 – Jun 13 |
| Bloom | August 8 | Aug 8 – Oct 17 |
Plant 0.1" deep · 12" apart · Rows 14" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | Transplant Outdoors |
| July | — |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 4b
📆 Growing Season
119 days in Judith Basin County
Growing Tips for Geraniums in Judith Basin County
Direct sow Geraniums outdoors after May 23 in Judith Basin County when soil has warmed and frost danger has passed.
Judith Basin County receives only 18" of rain annually. Geraniums needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Geraniums in Other Locations
Frequently Asked Questions
When should I plant Geraniums in Judith Basin County, MT?
Judith Basin County is in Zone 4b with an average last frost of May 23. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Judith Basin County, MT?
Judith Basin County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 23 and first fall frost is September 19.
When should I plant Geraniums in Judith Basin County, MT?
In Judith Basin County, MT, plant Geraniums after the last frost (around May 23) and before the first frost (around September 19). Best results when soil holds above 50°F.
What growing zone is Judith Basin County, MT for Geraniums?
Judith Basin County sits in USDA Zone 4b. Geraniums grows reliably in zones 2a through 11b, so it's a good fit here.
Can Geraniums grow in Judith Basin County's climate?
Yes — Geraniums grows well in Judith Basin County's temperate climate. Judith Basin County averages a 119-day frost-free season, with last frost around May 23 and first frost around September 19.
Your Judith Basin County Garden Planner — Free
A 22-page printable planner built for Judith Basin County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.