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When to Plant Lentils in Campbell County, SD

Campbell County, South Dakota Zone 4b May

May in the garden — Campbell County, South Dakota

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

Avg. last frost May 11
Avg. first frost September 30
Soil temp (4") 49°F
Watering Moderate
Pest pressure Low
Daylight 14.7 hrs
  1. Plant out lentils

    Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.

  2. Direct-sow lentils

    Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.

June will be here before you know it — start on
  • Starting indoors: lentils

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Lentils are an ancient pulse crop producing small, lens-shaped seeds packed with protein and iron. They grow on short, bushy plants and are surprisingly easy to cultivate.

Campbell County, South Dakota is in USDA Zone 4b. The average last spring frost is May 11 and the first fall frost is September 30, giving you a growing season of approximately 142 days.

At an elevation of 830 feet, Campbell County receives approximately 27.1 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Lentils to ensure they mature before fall.

Campbell County, SD (Zone 4b) Short season
142 days
Last Spring Frost May 11
142 growing days
First Fall Frost September 30

Campbell County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (18 days to spare)
Start indoors: Mar 21 Transplant: May 2 🍅 Harvest: Jul 25 – Sep 5
Recommended (50%) ✓ Fits season (16 days to spare)
Start indoors: Mar 30 Transplant: May 11 🍅 Harvest: Aug 3 – Sep 14
Safe Start (90%) ✓ Fits season (18 days to spare)
Start indoors: Apr 7 Transplant: May 19 🍅 Harvest: Aug 11 – Sep 22

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 Campbell County

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

Soil pH

Your soil pH (6.5–7.5) is within Lentils's preferred range (6.0–8.0).

Soil Texture

The loam soil in Campbell County is excellent for Lentils — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.8%). Annual compost additions will help Lentils.

How to Plant Lentils

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Plant Water Budget

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

Monthly Watering Guide for Lentils

Lentils 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 Lentils Needs Rainfall You Supplement Action
Jan 1.9" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 2.8" 0" ❄️ Dormant
May 2.6" 2.8" 0" ✅ Rainfall sufficient
Jun 2.6" 2" 0.6" 💧 Light watering
Jul 2.6" 2.2" 0.4" 💧 Light watering
Aug 2.6" 2.5" 0.1" 💧 Light watering
Sep 2.6" 2.4" 0.2" 💧 Light watering
Oct 2.5" 0" ❄️ Dormant
Nov 2.1" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Campbell County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Lentils 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.

Lentils needs ~950 GDD — county provides 1,420 GDD Excellent fit

Lentils Planting Timeline — Campbell County, SD

Lentils Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 – Apr 13
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Harvest August 3 Aug 3 – Sep 14
Fall Sowing July 8 Jul 8 – Jul 22

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.6"/week · Natural rainfall sufficient

📅 Days to Maturity

80–110 days

🧪 Soil pH

Needs 6–8 · Your soil: ideal

🗺️ USDA Zone

Zone 4b

📆 Growing Season

142 days in Campbell County

Growing Tips for Lentils in Campbell County

Direct sow Lentils outdoors after May 11 in Campbell County when soil has warmed and frost danger has passed.

Common pests for Lentils in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in early spring as lentils tolerate frost. Provide short supports as plants tend to lodge. Harvest when lower pods turn brown. Pull entire plants and dry in bundles.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lentils in Campbell County, SD?

Campbell County is in Zone 4b with an average last frost of May 11. Plan your Lentils planting based on this frost date — see the calendar above for exact timing.

What planting zone is Campbell County, SD?

Campbell County, South Dakota is in USDA Hardiness Zone 4b. The average last spring frost is May 11 and first fall frost is September 30.

🌱

Your Campbell County Garden Planner — Free

A 24-page printable planner built for Campbell 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.

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 Campbell County, SD. 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.