When to Plant Parsley in Sully County, SD
May in the garden — Sully County, South Dakota
Welcome to May in Zone 4b. These are the moves that will have the biggest impact on your growing season.
-
Harden off and plant parsley
Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.
-
Direct-sow parsley
Thin ruthlessly once seedlings are up. Crowded roots mean smaller crops from every plant.
Before June arrives, get these ready
- 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.
Sully County, South Dakota is in USDA Zone 4b. The average last spring frost is May 11 and the first fall frost is October 3, giving you a growing season of approximately 145 days.
At an elevation of 650 feet, Sully County receives approximately 26.8 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Parsley to ensure they mature before fall.
Sully County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.8
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 Sully County
How your county's soil matches Parsley's growing requirements.
Soil pH
Your soil pH (6.7–7.8) is more alkaline than Parsley prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Sully County is excellent for Parsley — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.6%). 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 15 to harvest before frost.
For a dedicated fall crop, sow by Jul 11.
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 | — | 2" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | — | 2.8" | 0" | ❄️ Dormant |
| May | 2.6" | 3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 2" | 0.6" | 💧 Light watering |
| Jul | 2.6" | 2.5" | 0.1" | 💧 Light watering |
| Aug | 2.6" | 2.8" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 2.3" | 0.3" | 💧 Light watering |
| Oct | 2.6" | 2.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 1.7" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Sully 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 — Sully County, SD
Parsley Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 30 | Mar 30 – Apr 13 |
| Transplant Outdoors | May 4 | May 4 – May 18 |
| Direct Sow | May 4 | May 4 – May 25 |
| Harvest | July 6 | Jul 6 – Sep 7 |
| 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 | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| 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 4b
📆 Growing Season
145 days in Sully County
Growing Tips for Parsley in Sully County
Direct sow Parsley outdoors after May 11 in Sully 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 Sully County, SD?
Sully County is in Zone 4b with an average last frost of May 11. Plan your Parsley planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sully County, SD?
Sully County, South Dakota is in USDA Hardiness Zone 4b. The average last spring frost is May 11 and first fall frost is October 3.
Your Sully County Garden Planner — Free
A 24-page printable planner built for Sully 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.