Blog

When to Plant Dill in Pennington County, SD

Dill is a feathery annual herb with aromatic leaves and seeds. Its fine foliage and umbrella-shaped flower heads attract beneficial insects to the garden.

Pennington County, South Dakota is in USDA Zone 4b. The average last spring frost is May 14 and the first fall frost is October 1, giving you a growing season of approximately 140 days.

At an elevation of 976 feet, Pennington County receives approximately 33.7 inches of rainfall annually with predominantly loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Dill to ensure they mature before fall.

Pennington County, SD (Zone 4b) Short season
140 days
Last Spring Frost May 14
140 growing days
First Fall Frost October 1

Pennington County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (36 days to spare)
Start indoors: Mar 29 Transplant: May 3 🍅 Harvest: Jun 14 – Aug 16
Recommended (50%) ✓ Fits season (42 days to spare)
Start indoors: Apr 2 Transplant: May 7 🍅 Harvest: Jun 18 – Aug 20
Safe Start (90%) ✓ Fits season (40 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: Jun 30 – Sep 1

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 Pennington County

How your county's soil matches Dill's growing requirements.

Soil pH

Your soil pH (6.3โ€“7.7) overlaps with Dill's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

The loam soil in Pennington County is excellent for Dill โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.7%). Annual compost additions will help Dill.

How to Plant Dill

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Dill

4
successive plantings in your 140-day season

Sow every 4.6 weeks. Last sowing by Aug 02 to harvest before frost.

For a dedicated fall crop, sow by Jul 09.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Dill

Dill needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Dill Needs Rainfall You Supplement Action
Jan โ€” 2.2" 0" โ„๏ธ Dormant
Feb โ€” 2" 0" โ„๏ธ Dormant
Mar โ€” 3" 0" โ„๏ธ Dormant
Apr โ€” 3.7" 0" โ„๏ธ Dormant
May 2.2" 3.6" 0" โœ… Rainfall sufficient
Jun 2.2" 2" 0.2" ๐Ÿ’ง Light watering
Jul 2.2" 3.1" 0" โœ… Rainfall sufficient
Aug 2.2" 3.5" 0" โœ… Rainfall sufficient
Sep 2.2" 3" 0" โœ… Rainfall sufficient
Oct 2.2" 3.2" 0" โœ… Rainfall sufficient
Nov โ€” 2.2" 0" โ„๏ธ Dormant
Dec โ€” 2.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Pennington County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Dill 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" โ€” every day above 50ยฐF 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.

Dill needs ~612 GDD — county provides 1,715 GDD Excellent fit

Dill Planting Timeline โ€” Pennington County, SD

Dill Planting Calendar

Activity When Date Range
Start Indoors April 2 Apr 2 โ€“ Apr 16
Transplant Outdoors May 7 May 7 โ€“ May 21
Direct Sow May 7 May 7 โ€“ May 28
Harvest June 18 Jun 18 โ€“ Aug 20
Fall Sowing July 9 Jul 9 โ€“ Jul 23

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

140 days in Pennington County

Growing Tips for Dill in Pennington County

Direct sow Dill outdoors after May 14 in Pennington County when soil has warmed and frost danger has passed.

Common pests for Dill in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring as dill has a taproot and dislikes transplanting. Succession sow for continuous leaf harvest. Allow some plants to flower for seeds and to attract beneficial insects.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Dill in Pennington County, SD?

Pennington County is in Zone 4b with an average last frost of May 14. Plan your Dill planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pennington County, SD?

Pennington County, South Dakota is in USDA Hardiness Zone 4b. The average last spring frost is May 14 and first fall frost is October 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pennington County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Pennington County, SD. Local conditions may vary. Last updated: April 2026.