Blog

When to Plant Dill in Sullivan County, MO

Sullivan County, Missouri Zone 6a May

May in the garden — Sullivan County, Missouri

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Sullivan County, Missouri.

Avg. last frost April 17
Avg. first frost October 17
Soil temp (4") 59°F
Watering Low
Pest pressure Low
Daylight 14.2 hrs
  1. Time to start dill inside

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Pick dill

    If you can't use it all right away, check the food-preservation section of your planner.

June will be here before you know it — start on
  • First harvests: dill

Instant PDF download. No spam, unsubscribe any time.

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.

Sullivan County, Missouri is in USDA Zone 6a. The average last spring frost is April 17 and the first fall frost is October 17, giving you a growing season of approximately 183 days.

At an elevation of 1,019 feet, Sullivan County receives approximately 34.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Dill to ensure they mature before fall.

Sullivan County, MO (Zone 6a) Moderate season
183 days
Last Spring Frost April 17
183 growing days
First Fall Frost October 17
Share this guide:

Sullivan County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (83 days to spare)
Start indoors: Mar 8 Transplant: Apr 5 🍅 Harvest: May 17 – Jul 19
Recommended (50%) ✓ Fits season (85 days to spare)
Start indoors: Mar 13 Transplant: Apr 10 🍅 Harvest: May 22 – Jul 24
Safe Start (90%) ✓ Fits season (85 days to spare)
Start indoors: Mar 27 Transplant: Apr 24 🍅 Harvest: Jun 5 – Aug 7

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 Sullivan County

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

Soil pH

Your soil pH (5.5–6.8) is within Dill's preferred range (5.5–7.0).

Soil Texture

The silt loam soil in Sullivan County is excellent for Dill — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Dill.

How to Plant Dill

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Dill

5
successive plantings in your 183-day season

Sow every 4.6 weeks. Last sowing by Aug 18 to harvest before frost.

For a dedicated fall crop, sow by Aug 08.

Plant Water Budget

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

Water stress score is 6/10 — 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 1.4" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 2.2" 3.1" 0" ✅ Rainfall sufficient
May 2.2" 4" 0" ✅ Rainfall sufficient
Jun 2.2" 4.2" 0" ✅ Rainfall sufficient
Jul 2.2" 3.9" 0" ✅ Rainfall sufficient
Aug 2.2" 3.2" 0" ✅ Rainfall sufficient
Sep 2.2" 3.3" 0" ✅ Rainfall sufficient
Oct 2.2" 2.6" 0" ✅ Rainfall sufficient
Nov 2.7" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Sullivan County). Supplement amounts are based on average rainfall — 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" — 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.

Dill needs ~650 GDD — county provides 2,379 GDD Excellent fit

Dill Planting Timeline — Sullivan County, MO

Dill Planting Calendar

Activity When Date Range
Start Indoors March 13 Mar 13 – Mar 27
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow April 3 Apr 3 – Apr 24
Harvest May 22 May 22 – Jul 24
Fall Sowing August 8 Aug 8 – Aug 22

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
August Fall Sowing
September
October
November
December
Share this guide:

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

183 days in Sullivan County

Growing Tips for Dill in Sullivan County

Direct sow Dill outdoors after April 17 in Sullivan County when soil has warmed and frost danger has passed.

Your generous 183.0-day season in Sullivan County allows multiple plantings of Dill. Sow every 20.0 days for continuous harvest.

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 Sullivan County, MO?

Sullivan County is in Zone 6a with an average last frost of April 17. Plan your Dill planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sullivan County, MO?

Sullivan County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 17 and first fall frost is October 17.

🌱

Your Sullivan County Garden Planner — Free

A 24-page printable planner built for Sullivan County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.