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When to Plant Chard in St. Lawrence County, NY

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.

St. Lawrence County, New York is in USDA Zone 4a. The average last spring frost is May 10 and the first fall frost is October 2, giving you a growing season of approximately 145 days.

At an elevation of 688 feet, St. Lawrence County receives approximately 39.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Chard to ensure they mature before fall.

St. Lawrence County, NY (Zone 4a) Short season
145 days
Last Spring Frost May 10
145 growing days
First Fall Frost October 2

St. Lawrence County Soil Profile

Soil Type

Silt Loam

Soil pH

4.9-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (45 days to spare)
Start indoors: Mar 20 Transplant: May 1 🍅 Harvest: Jun 26 – Aug 14
Recommended (50%) ✓ Fits season (40 days to spare)
Start indoors: Mar 29 Transplant: May 10 🍅 Harvest: Jul 5 – Aug 23
Safe Start (90%) ✓ Fits season (40 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 St. Lawrence County

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

Soil pH

Your soil pH (4.9โ€“6.6) is more acidic than Chard prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in St. Lawrence County is excellent for Chard โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.9%). 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 145-day season

Sow every 5.7 weeks. Last sowing by Aug 03 to harvest before frost.

For a dedicated fall crop, sow by Jul 10.

Plant Water Budget

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

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 โ€” 2.7" 0" โ„๏ธ Dormant
Feb โ€” 2.6" 0" โ„๏ธ Dormant
Mar โ€” 3.4" 0" โ„๏ธ Dormant
Apr โ€” 3.1" 0" โ„๏ธ Dormant
May 3.5" 3.8" 0" โœ… Rainfall sufficient
Jun 3.5" 3.6" 0" โœ… Rainfall sufficient
Jul 3.5" 4.4" 0" โœ… Rainfall sufficient
Aug 3.5" 3.3" 0.2" ๐Ÿ’ง Light watering
Sep 3.5" 3.2" 0.3" ๐Ÿ’ง Light watering
Oct 3.5" 2.9" 0.6" ๐Ÿ’ง Light watering
Nov โ€” 2.9" 0" โ„๏ธ Dormant
Dec โ€” 3.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in St. Lawrence County). Supplement amounts are based on average rainfall โ€” 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" 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.

Chard needs ~715 GDD — county provides 1,885 GDD Excellent fit

Chard Planting Timeline โ€” St. Lawrence County, NY

Chard Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 โ€“ Apr 12
Transplant Outdoors May 10 May 10 โ€“ May 24
Direct Sow May 3 May 3 โ€“ May 24
Harvest July 5 Jul 5 โ€“ Aug 23
Fall Sowing July 10 Jul 10 โ€“ Jul 24

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.8"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

50โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

145 days in St. Lawrence County

Growing Tips for Chard in St. Lawrence County

Direct sow Chard outdoors after May 10 in St. Lawrence 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 St. Lawrence County, NY?

St. Lawrence County is in Zone 4a with an average last frost of May 10. Plan your Chard planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is St. Lawrence County, NY?

St. Lawrence County, New York is in USDA Hardiness Zone 4a. The average last spring frost is May 10 and first fall frost is October 2.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help St. Lawrence County gardeners in Zone 4a 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 St. Lawrence County, NY. Local conditions may vary. Last updated: April 2026.