Zone 3 · Leafy Greens Growing Guide

When to Plant Swiss Chard
in Zone 3

More heat-tolerant than spinach, more cold-hardy than most greens. Rainbow chard is also ornamental. One of the most versatile and productive crops per square foot.

Plant outdoors
May 1 – Aug 1
Start indoors
Direct sow
Last Frost
~May 15
Days to harvest
50–60 days
Difficulty
Easy
Wrong season — Zone 3
Harvest window: Jun – Nov

Planting Calendar

In Zone 3, Swiss Chard should be planted outdoors May 1 – Aug 1, after the average last frost date of approximately May 15.

Direct sow spring through summer. Frost-hardy — keeps producing until hard freeze.

Care Guide

Sunlight
Full sun to partial shade · 4–8 hrs/day
Watering
Regular
Spacing
6–9 inches
Soil
Well-draining, fertile
Days to maturity
50–60 days
Soil pH
6.0–7.5
plant tip · Zone 3

Direct sow spring through summer. Frost-hardy — keeps producing until hard freeze.

Feeding Schedule

How often
monthly
Feed type
high nitrogen
Key timing
throughout growing season

Like spinach, chard is a heavy nitrogen feeder. Monthly liquid feed keeps growth vigorous all season.

Succession Planting

Sow every 4 weeks

Sow every 4 weeks from spring through early summer. Chard is a cut-and-come-again crop, so each sowing produces over a long period.

Companion Planting for Swiss Chard

What you plant next to swiss chard makes a real difference — some plants actively help, others compete or attract pests.

Grows well with
  • Beans
  • Brassicas
  • Onions
Keep away from
  • Corn
  • Potatoes
  • Fennel

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Common questions

In Zone 3, direct sow swiss chard outdoors May 1 – Aug 1 after your last frost date of approximately May 15. Direct sow spring through summer. Frost-hardy — keeps producing until hard freeze.
Zone 3 has an average last spring frost of approximately May 15 and a first fall frost around Sep 15. These dates vary by specific location — use your ZIP code in the plant app for precision based on the nearest NOAA weather station.
Good companion crops for swiss chard include Beans, Brassicas, Onions. Avoid planting near Corn, Potatoes, Fennel, which can compete for nutrients or attract pests.
Swiss Chard typically takes 50–60 days from transplant or direct sow to harvest in Zone 3. Expected harvest window: Jun – Nov.

Free app · iOS February 2028

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