Blog

When to Plant Chard in Jackson County, SD

Jackson County, South Dakota Zone 4a April

April in Jackson County, South Dakota — your action list

Your garden in Jackson County, South Dakota is working on a schedule, even when you're not. Here's where you should be this April.

Avg. last frost May 14
Avg. first frost September 28
Soil temp (4") 42°F
Watering High
Pest pressure Low
Daylight 13.2 hrs
May prep starts now
  • Transplants going out: chard
  • Direct-sowing: chard

Instant PDF download. No spam, unsubscribe any time.

Swiss chard is a colorful, heat-tolerant green with large crinkled leaves and vibrant stalks in red, yellow, and white. Both the leaves and stems are edible and nutritious.

Jackson County, South Dakota is in USDA Zone 4a. The average last spring frost is May 14 and the first fall frost is September 28, giving you a growing season of approximately 137 days.

At an elevation of 1,001 feet, Jackson County receives approximately 20.1 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Chard to ensure they mature before fall.

Jackson County, SD (Zone 4a) Short season
137 days
Last Spring Frost May 14
137 growing days
First Fall Frost September 28

Jackson County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (30 days to spare)
Start indoors: Mar 28 Transplant: May 9 🍅 Harvest: Jul 4 – Aug 22
Recommended (50%) ✓ Fits season (32 days to spare)
Start indoors: Apr 2 Transplant: May 14 🍅 Harvest: Jul 9 – Aug 27
Safe Start (90%) ✓ Fits season (29 days to spare)
Start indoors: Apr 14 Transplant: May 26 🍅 Harvest: Jul 21 – Sep 8

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 Jackson County

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

Soil pH

Your soil pH (6.4–7.8) is more alkaline than Chard prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

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

How to Plant Chard

1"
Planting Depth
15"
Between Plants
24"
Between Rows

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

Succession Planting Chard

3
successive plantings in your 137-day season

Sow every 5.7 weeks. Last sowing by Jul 30 to harvest before frost.

For a dedicated fall crop, sow by Jul 06.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.6″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 269 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Chard

Chard needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Chard Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 2.3" 0" ❄️ Dormant
May 3.5" 2.4" 1.1" 💧 Light watering
Jun 3.5" 1.5" 2" 🚿 Regular watering
Jul 3.5" 1.9" 1.6" 💧 Light watering
Aug 3.5" 1.9" 1.6" 💧 Light watering
Sep 3.5" 1.6" 1.9" 🚿 Regular watering
Oct 1.7" 0" ❄️ Dormant
Nov 1.2" 0" ❄️ Dormant
Dec 1.2" 0" ❄️ Dormant

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

Chard 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.

Chard needs ~550 GDD — county provides 1,370 GDD Excellent fit

Chard Planting Timeline — Jackson County, SD

Chard Planting Calendar

Activity When Date Range
Start Indoors April 2 Apr 2 – Apr 16
Transplant Outdoors May 14 May 14 – May 28
Direct Sow May 7 May 7 – May 28
Harvest July 9 Jul 9 – Aug 27
Fall Sowing July 6 Jul 6 – Jul 20

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.8"/week · Only during dry spells

📅 Days to Maturity

50–60 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 4a

📆 Growing Season

137 days in Jackson County

Growing Tips for Chard in Jackson County

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

General growing tips

Direct sow or transplant after last frost. Harvest outer leaves regularly to encourage continuous production. Chard tolerates both heat and light frost.

Companion Planting

Good Companions

Avoid Planting Near

  • Corn
  • Cucumbers

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Chard in Jackson County, SD?

Jackson County is in Zone 4a with an average last frost of May 14. Plan your Chard planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, SD?

Jackson County, South Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 14 and first fall frost is September 28.

🌱

Your Jackson County Garden Planner — Free

A 24-page printable planner built for Jackson County (Zone 4a). 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 Jackson County, SD. Local conditions may vary. Last updated: April 2026.

Sources & credits

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