When to Plant Parsley in Valley County, ID
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.
Valley County, Idaho is in USDA Zone 4b. The average last spring frost is June 18 and the first fall frost is September 3, giving you a growing season of approximately 77 days.
At an elevation of 7,884 feet, Valley County receives approximately 17.8 inches of rainfall annually with predominantly loam soil. Summer highs average 83°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.
Valley County Soil Profile
Soil Type
Loam
Soil pH
6.4-8.4
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 Valley County
How your county's soil matches Parsley's growing requirements.
Soil pH
Your soil pH (6.4–8.4) is more alkaline than Parsley prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Valley 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.
Plant Water Budget
Water stress score is 8/10 — 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 | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 2.2" | 0" | ❄️ Dormant |
| May | — | 2.1" | 0" | ❄️ Dormant |
| Jun | 2.6" | 1.1" | 1.5" | 🚿 Regular watering |
| Jul | 2.6" | 1.5" | 1.1" | 💧 Light watering |
| Aug | 2.6" | 1.9" | 0.7" | 💧 Light watering |
| Sep | 2.6" | 1.4" | 1.2" | 💧 Light watering |
| Oct | — | 1.5" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Valley 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 — Valley County, ID
Parsley Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 7 | May 7 – May 21 |
| Transplant Outdoors | June 11 | Jun 11 – Jun 25 |
| Direct Sow | June 11 | Jun 11 – Jul 2 |
| Harvest | August 13 | Aug 13 – Oct 15 |
| Fall Sowing | June 11 | Jun 11 – Jun 25 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Direct Sow |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| 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 4b
📆 Growing Season
77 days in Valley County
Growing Tips for Parsley in Valley County
Direct sow Parsley outdoors after June 18 in Valley County when soil has warmed and frost danger has passed.
Your 77.0-day growing season in Valley County is tight for Parsley (60.0-80.0 days to maturity). Start indoors and choose early-maturing varieties.
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 Valley County, ID?
Valley County is in Zone 4b with an average last frost of June 18. Plan your Parsley planting based on this frost date — see the calendar above for exact timing.
What planting zone is Valley County, ID?
Valley County, Idaho is in USDA Hardiness Zone 4b. The average last spring frost is June 18 and first fall frost is September 3.
Plan Your Garden with Confidence
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