Planting timing · Cool-season
When to plant Swiss chard
Plant Swiss chard on the cited sheets — not on a national calendar month. Regional dates stay source-specific.
Growing guidance is general information. Timing, spacing, and care depend on cultivar, weather, soil, and local conditions. Check the sources and adjust the plan for your garden.
Spacing lives on the Swiss chard hub. Timing stays on the cited sheets.
Types and spacing live on growing Swiss chard.
What the sources say — at a glance
One source per card. Facts are not averaged.
Clemson HGIC 1329 (South Carolina)
Direct sow spring or late summer. Piedmont Mar 12–Jun 30 and Jul 15–Sep 30. Coastal Feb 1–Jun 15 and Aug 1–Oct 30. SC regions.
Details and limits (3)
Timing
Clemson HGIC 1329 (South Carolina): sow Swiss chard directly into the garden in spring or late summer. Timing on their sheet — not a national plant date.
Regions
Clemson HGIC 1329 (South Carolina): Piedmont March 12 to June 30 and July 15 to September 30. Coastal Plain February 1 to June 15 and August 1 to October 30. South Carolina regions on the greens sheet — not a national plant date.
Limit
South Carolina HGIC 1329. Regional dates stay Clemson. Not a ZIP calendar.
Maryland Extension (Maryland)
Early spring and late summer direct seed. Indoor 5–6 weeks. Maryland timing — not a national plant date.
Details and limits (2)
Timing
Maryland Extension (Maryland): direct seed into the garden in early spring and late summer. Seeds can also be started indoors 5 to 6 weeks prior to transplanting. Maryland timing — not a national plant date.
Limit
Maryland Swiss chard garden page. Early-spring and late-summer timing stays Maryland. Not a ZIP calendar.
UMN Extension (Minnesota)
Early to mid-May. Indoor early April / 4 weeks. Fall indoor June. Minnesota timing — not a national plant date.
Details and limits (2)
Timing
UMN Extension (Minnesota): start chard in early to mid-May. For summer crops, plant seed indoors in early April or about four weeks before transplanting. For fall crops, sow seed indoors in June. Minnesota timing — not a national plant date.
Limit
Minnesota chard/spinach sheet. Chard timing stays Minnesota. Not a ZIP calendar.
Illinois Extension (Illinois)
Early to mid-spring direct seed. Indoor or cold frame early spring. Illinois timing — not a national plant date.
Details and limits (2)
Timing
Illinois Extension (Illinois): chard can be directly seeded into the garden in early spring to mid-spring. Sow seed indoors or in a cold frame in early spring. Illinois timing — not a national plant date.
Limit
Illinois chard page. Early-to-mid-spring timing stays Illinois. Not a ZIP calendar.
Sources differ
Make it yours
Save the bed in the Field Book so next season is not a guess.
Verified suppliers only
No supplier on this page
When a partner is listed, it will be outbound and disclosed. Nothing to buy here. Fertilizer, soils, and pesticides stay off this slot.
When do you plant Swiss chard?
Compare timing on the cited sheets. Clemson HGIC 1329 (South Carolina): direct sow in spring or late summer. Maryland: early spring and late summer, or indoor 5 to 6 weeks. Minnesota: early to mid-May. Illinois: early to mid-spring.
Do the sheets agree on a window?
No. Clemson names spring or late summer, with Piedmont and Coastal dates as South Carolina regions. Maryland names early spring and late summer. Minnesota names early to mid-May. Illinois names early to mid-spring. Four cards — not averaged.
What to record in the Field Book
Save the bed with the crop and the date. You may add a photo and notes. Compare entries you have recorded with each other — not with a diagnosis from this page. If you want an identification, bring the record to local Extension.
How we know — methodology. Ranges and assertions are cited per source, not blended.