Tatsoi · Philadelphia, Pennsylvania, United States
When to plant tatsoi in Philadelphia
Main outdoor window
24 Mar - 21 Apr
The window this page is built around.
Timed from last spring frost
14 April
In Philadelphia, on your chosen risk.
Ready to pick
1 May - 30 Nov
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 Philadelphia
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.
Sow for overwintering
9-30 Aug
Counting back 64 days from your first frost so the crop matures in time.
Sow direct
24 Mar - 21 Apr
Three weeks before your last frost.
Harvest
1 May - 30 Nov
Tatsoi through the year
Against the frost risk in Philadelphia
Why these dates
Sow from three weeks before the last frost, and again in late summer for the crop that matters. Autumn sowings hold in good condition for weeks.
Hardy to about -8C and often found still green under snow, the low rosette acting as its own insulation.
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. Tatsoi are timed for direct sowing 3 weeks before it, and this page simply resolves those offsets against the frost date computed for Philadelphia.
The median frost-free season here is 202 days, against 40 to 50 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Philadelphia
Other vegetables to time
Growing tatsoi in Philadelphia
When should I plant tatsoi in Philadelphia?
Aim for 24 Mar - 21 Apr in an average year. If you would rather not gamble on the weather, wait until 2-30 Apr - by then frost has finished in nine years out of ten.
When will tatsoi be ready to harvest in Philadelphia?
Expect to start picking around 1 May - 30 Nov, based on 40 to 50 days to maturity from the planting date calculated for this location.
How much frost will tatsoi tolerate?
Hardy to about -8C and often found still green under snow, the low rosette acting as its own insulation.