Safe to Plant

Dill · Philadelphia, Pennsylvania, United States

When to plant dill in Philadelphia

Main outdoor window

14-24 Apr

The window this page is built around.

Timed from last spring frost

14 April

In Philadelphia, on your chosen risk.

Ready to pick

24 May - 13 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 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

14-24 Apr

Around your last frost.

Harvest

24 May - 13 Jun

Sow in succession. A single sowing gives you a single glut. Sow a short row every 21 days through the window above and you get a steady supply instead.
Frost tolerance
Half-hardy
Damaged below
-4°C (24.8°F)
Days to maturity
40–60
Min soil temp
10°C (50°F)
Spacing
20 cm
Sowing depth
6 mm (0.2 in)
Sun
Full

Dill through the year

Against the frost risk in Philadelphia

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Frost risk Sow direct Harvest Today

Why these dates

Sow at the last frost date and again every three weeks. Each plant is short-lived, so succession is the only way to keep leaf coming.

Seedlings handle a light frost. Self-seeds freely and often returns without being asked.

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. Dill are timed for direct sowing 0 weeks after 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 60 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.

See every crop timed for Philadelphia →

Growing dill in Philadelphia

When should I plant dill in Philadelphia?

Aim for 14-24 Apr in an average year. If you would rather not gamble on the weather, wait until 23 Apr - 3 May - by then frost has finished in nine years out of ten.

When will dill be ready to harvest in Philadelphia?

Expect to start picking around 24 May - 13 Jun, based on 40 to 60 days to maturity from the planting date calculated for this location.

How much frost will dill tolerate?

Seedlings handle a light frost. Self-seeds freely and often returns without being asked.