Vegetable · Apiaceae
When to plant celery
Demanding: long season, constant moisture, and a dislike of both cold and heat.
Start seed indoors
10 weeks before
Counted from your last spring frost.
Plant out
2 weeks after
Counted from your last spring frost.
Days to maturity
80-100
From planting out to a first picking.
Those weeks become real dates once you name a place.
Timing, in frost-relative terms
Seed packets rarely give calendar dates, because a date that suits one latitude is wrong at another. They give offsets from the last spring frost instead, and those offsets are what make celery plantable anywhere.
- Start seed indoors 10 weeks before the last frost.
- Plant out 2 weeks after the last frost.
- Expect 80–100 days to maturity, counted from planting out.
Getting the timing right
Start ten weeks before last frost but plant out two weeks after it. Celery exposed to a fortnight below 10C after transplanting will bolt rather than form heads.
Frost tolerance
Light frost is tolerated at maturity, but cold early in life triggers bolting. This crop is unusual in that too-early planting causes failure without any visible frost damage.
Classified as half-hardy, with damage expected below -3°C (26.6°F)26.6°F (-3°C).