When to Plant Parsley in Bonneville County, ID
Your May gardening checklist
Each item below is timed to Bonneville County, Idaho's frost dates and soil temperatures. Skip nothing, stress about nothing.
-
Move parsley from tray to bed
Your last frost (May 26) has passed. These warm-season crops can handle outdoor soil now.
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Seed parsley outdoors
Your soil is 32°F — warm enough for these to germinate without babying.
June will be here before you know it — start on
- Starting indoors: parsley
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.
Bonneville County, Idaho is in USDA Zone 5b. The average last spring frost is May 26 and the first fall frost is September 19, giving you a growing season of approximately 116 days.
At an elevation of 7,993 feet, Bonneville County receives approximately 20.9 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Parsley during the growing season.
Bonneville County Soil Profile
Soil Type
Loam
Soil pH
6.5-8
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 Bonneville County
How your county's soil matches Parsley's growing requirements.
Soil pH
Your soil pH (6.5–8.0) is more alkaline than Parsley prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Bonneville County is excellent for Parsley — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Parsley.
How to Plant Parsley
Fall planting: Sow 10 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 Jul 11.
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 2" | 0" | ❄️ Dormant |
| Apr | — | 2.4" | 0" | ❄️ Dormant |
| May | 2.6" | 2.2" | 0.4" | 💧 Light watering |
| Jun | 2.6" | 1.7" | 0.9" | 💧 Light watering |
| Jul | 2.6" | 2.1" | 0.5" | 💧 Light watering |
| Aug | 2.6" | 1.9" | 0.7" | 💧 Light watering |
| Sep | 2.6" | 1.7" | 0.9" | 💧 Light watering |
| Oct | — | 1.9" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Bonneville 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 — Bonneville County, ID
Parsley Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 21 | Apr 21 – May 5 |
| Transplant Outdoors | May 19 | May 19 – Jun 2 |
| Direct Sow | May 12 | May 12 – Jun 2 |
| Harvest | July 21 | Jul 21 – Sep 22 |
| Fall Sowing | July 11 | Jul 11 – Jul 25 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| 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 5b
📆 Growing Season
116 days in Bonneville County
Growing Tips for Parsley in Bonneville County
Direct sow Parsley outdoors after May 26 in Bonneville 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 Bonneville County, ID?
Bonneville County is in Zone 5b with an average last frost of May 26. Plan your Parsley planting based on this frost date — see the calendar above for exact timing.
What planting zone is Bonneville County, ID?
Bonneville County, Idaho is in USDA Hardiness Zone 5b. The average last spring frost is May 26 and first fall frost is September 19.
Your Bonneville County Garden Planner — Free
A 24-page printable planner built for Bonneville County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.