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When to Plant Lentils in Yankton County, SD

Yankton County, South Dakota Zone 5a May

May in the garden — Yankton County, South Dakota

Welcome to May in Zone 5a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 1
Avg. first frost October 6
Soil temp (4") 60°F
Watering Moderate
Pest pressure Low
Daylight 14.5 hrs
  1. Move lentils into the garden

    Bring a watering can to the bed. Each transplant gets a drink the moment it's in the ground, not ten minutes later.

Before June arrives, get these ready
  • 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.

Yankton County, South Dakota is in USDA Zone 5a. The average last spring frost is May 1 and the first fall frost is October 6, giving you a growing season of approximately 158 days.

At an elevation of 606 feet, Yankton County receives approximately 21.8 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Lentils to ensure they mature before fall.

Yankton County, SD (Zone 5a) Moderate season
158 days
Last Spring Frost May 1
158 growing days
First Fall Frost October 6

Yankton County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (35 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: Jul 17 – Aug 28
Recommended (50%) ✓ Fits season (32 days to spare)
Start indoors: Mar 27 Transplant: May 1 🍅 Harvest: Jul 24 – Sep 4
Safe Start (90%) ✓ Fits season (28 days to spare)
Start indoors: Apr 9 Transplant: May 14 🍅 Harvest: Aug 6 – Sep 17

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 Yankton County

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

Soil pH

Your soil pH (6.2–7.8) is within Lentils's preferred range (6.0–8.0).

Soil Texture

The loam soil in Yankton 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 10 weeks before your first frost date for a fall harvest.

Succession Planting Lentils

2
successive plantings in your 158-day season

Sow every 9.1 weeks. Last sowing by Jun 18 to harvest before frost.

For a dedicated fall crop, sow by Jul 28.

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
0.6″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 35 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 0.5" 0" ❄️ Dormant
Feb 0.6" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 2.5" 0" ❄️ Dormant
May 2.6" 3.6" 0" ✅ Rainfall sufficient
Jun 2.6" 3.8" 0" ✅ Rainfall sufficient
Jul 2.6" 2.6" 0" ✅ Rainfall sufficient
Aug 2.6" 2.4" 0.2" 💧 Light watering
Sep 2.6" 1.9" 0.7" 💧 Light watering
Oct 2.6" 1.2" 1.4" 🚿 Regular watering
Nov 0.7" 0" ❄️ Dormant
Dec 0.6" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Yankton 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 ~1,235 GDD — county provides 2,054 GDD Excellent fit

Lentils Planting Timeline — Yankton County, SD

Lentils Planting Calendar

Activity When Date Range
Start Indoors March 27 Mar 27 – Apr 10
Transplant Outdoors May 1 May 1 – May 15
Direct Sow April 17 Apr 17 – May 8
Harvest July 24 Jul 24 – Sep 4
Fall Sowing July 28 Jul 28 – Aug 11

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.6"/week · Only during dry spells

📅 Days to Maturity

80–110 days

🧪 Soil pH

Needs 6–8 · Your soil: ideal

🗺️ USDA Zone

Zone 5a

📆 Growing Season

158 days in Yankton County

Growing Tips for Lentils in Yankton County

Direct sow Lentils outdoors after May 01 in Yankton 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 Yankton County, SD?

Yankton County is in Zone 5a with an average last frost of May 1. Plan your Lentils planting based on this frost date — see the calendar above for exact timing.

What planting zone is Yankton County, SD?

Yankton County, South Dakota is in USDA Hardiness Zone 5a. The average last spring frost is May 1 and first fall frost is October 6.

🌱

Your Yankton County Garden Planner — Free

A 24-page printable planner built for Yankton County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Yankton 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.