Cress · Philadelphia, Pennsylvania, United States
When to plant cress in Philadelphia
Main outdoor window
17 Mar - 12 May
The window this page is built around.
Timed from last spring frost
14 April
In Philadelphia, on your chosen risk.
Ready to pick
1 Apr - 31 Oct
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 direct
17 Mar - 12 May
Four weeks before your last frost.
Harvest
1 Apr - 31 Oct
Cress through the year
Against the frost risk in Philadelphia
Why these dates
Sow thickly every week from four weeks before the last frost. It needs no space, no depth and no waiting, so it fills the edges of beds all season.
Damaged below about -3C, but the crop is over so quickly that frost rarely gets the chance to reach it.
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. Cress are timed for direct sowing 4 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 14 to 21 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 cress in Philadelphia
When should I plant cress in Philadelphia?
Aim for 17 Mar - 12 May in an average year. If you would rather not gamble on the weather, wait until 26 Mar - 21 May - by then frost has finished in nine years out of ten.
When will cress be ready to harvest in Philadelphia?
Expect to start picking around 1 Apr - 31 Oct, based on 14 to 21 days to maturity from the planting date calculated for this location.
How much frost will cress tolerate?
Damaged below about -3C, but the crop is over so quickly that frost rarely gets the chance to reach it.