Swiss chard · Edmonton, Alberta, Canada
When to plant swiss chard in Edmonton
Main outdoor window
29 Apr - 20 May
The window this page is built around.
Timed from last spring frost
13 May
In Edmonton, on your chosen risk.
Ready to pick
18-28 Jun
If you plant at the start of the window.
The average last frost. Half of all years are later than this.
Step by step in Edmonton
Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.
Start indoors
8-29 Apr
Five weeks before your last frost, under cover or on a windowsill.
Sow for overwintering
23 Jun - 14 Jul
Counting back 74 days from your first frost so the crop matures in time.
Sow direct
29 Apr - 20 May
Two weeks before your last frost.
Plant out
6-27 May
One week before your last frost.
Harvest
18-28 Jun
Swiss chard through the year
Against the frost risk in Edmonton
Why these dates
One spring sowing usually lasts until hard frost. In mild climates it overwinters and produces an early spring flush before bolting.
Takes -5C without protection. Under a cloche it will hold through much colder weather and resume growth in late winter.
Seed packets and extension guides express timing as weeks either side of the last spring frost, because that is the only reference point that travels. Swiss chard are timed from 5 weeks before that frost for an indoor start, with planting out 1 weeks before it, and this page simply resolves those offsets against the frost date computed for Edmonton.
The median frost-free season here is 137 days, against 50 to 60 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Edmonton
Other vegetables to time
Growing swiss chard in Edmonton
When should I plant swiss chard in Edmonton?
Aim for 29 Apr - 20 May in an average year. If you would rather not gamble on the weather, wait until 8-29 May - by then frost has finished in nine years out of ten.
When will swiss chard be ready to harvest in Edmonton?
Expect to start picking around 18-28 Jun, based on 50 to 60 days to maturity from the planting date calculated for this location.
How much frost will swiss chard tolerate?
Takes -5C without protection. Under a cloche it will hold through much colder weather and resume growth in late winter.