When to Plant Parsley in Judith Basin County, MT
Parsley is a biennial herb available in flat-leaf (Italian) and curly varieties. It is a nutritional powerhouse rich in vitamins C and K and adds fresh flavor to countless dishes.
Judith Basin County, Montana is in USDA Zone 4a. 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 Parsley to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Parsley successfully. Mulch heavily to conserve soil moisture.
Judith Basin County Soil Profile
Soil Type
Loam
Soil pH
6.5-8.2
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 Judith Basin County
How your county's soil matches Parsley's growing requirements.
Soil pH
Your soil pH (6.5–8.2) is more alkaline than Parsley 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 Parsley — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Parsley.
How to Plant Parsley
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Parsley
Sow every 6.9 weeks. Last sowing by Jul 01 to harvest before frost.
For a dedicated fall crop, sow by Jun 27.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Parsley
Parsley needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.
| Month | Parsley 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 | 2.6" | 2.2" | 0.4" | 💧 Light watering |
| Jun | 2.6" | 1.3" | 1.3" | 🚿 Regular watering |
| Jul | 2.6" | 1.7" | 0.9" | 💧 Light watering |
| Aug | 2.6" | 1.9" | 0.7" | 💧 Light watering |
| Sep | 2.6" | 1.4" | 1.2" | 💧 Light 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.
Parsley 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.
Parsley Planting Timeline — Judith Basin County, MT
Parsley Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 11 | Apr 11 – Apr 25 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Direct Sow | May 16 | May 16 – Jun 6 |
| Harvest | July 18 | Jul 18 – Sep 19 |
| Fall Sowing | June 27 | Jun 27 – Jul 11 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Direct Sow Fall Sowing |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.6"/week · Natural rainfall sufficient
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 4a
📆 Growing Season
119 days in Judith Basin County
Growing Tips for Parsley in Judith Basin County
Direct sow Parsley outdoors after May 23 in Judith Basin County when soil has warmed and frost danger has passed.
Common pests for Parsley in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Soak seeds overnight as germination is slow. Harvest outer stems first to keep plants productive. Parsley attracts swallowtail butterflies.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Parsley in Other Locations
Frequently Asked Questions
When should I plant Parsley in Judith Basin County, MT?
Judith Basin County is in Zone 4a with an average last frost of May 23. Plan your Parsley 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 4a. The average last spring frost is May 23 and first fall frost is September 19.
Plan Your Garden with Confidence
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