🥬 Celery

Apium graveolens var. dulce
The marathon runner of the garden — 140 days, constant water, worth every minute.
Sun
Full sun to partial shade, 6 hrs (afternoon shade in heat)
Days to harvest
120-140 from transplant
Spacing
6-8 inches apart, rows 18 inches apart
Soil pH
6.0-7.0

How to grow

Start indoors 10-12 weeks before your last frost — celery seeds are microscopic, slow (up to 3 weeks to germinate), and need light, so press them onto the surface and don't cover. Keep them at 70°F and constantly moist; a humidity dome is your friend. Transplant only after nights stay above 50°F — cold triggers bolting. In Florida, celery is a winter crop: start seeds in August, transplant October, harvest January-March. Up north, it's a long-season summer crop. Celery is a bog plant at heart — it evolved in marshes, so rich, moisture-retentive soil is mandatory. Work in heavy compost and 5-10% worm castings. Blanching (mounding soil or wrapping stalks) gives tender, mild celery; unblanched is stronger-flavored and more nutritious. Your call.

Water & feeding

This is the thirstiest common vegetable — it needs consistently moist soil, always. An inch-plus per week, more in heat; mulch heavily to hold moisture. Any drought stress gives you hollow, bitter, stringy stalks. Drip irrigation is ideal. Feed monthly with compost tea or a castings top-dress — celery is a heavy feeder over its long season, and steady nutrition prevents the pithy hollow-stalk problem.

Common problems

  • Bolting from cold exposure — transplant only after nights are reliably warm; choose slow-bolting varieties.
  • Hollow, bitter stalks — drought stress or boron deficiency; consistent water and compost-rich soil fix both.
  • Slugs love the moist conditions celery demands — iron phosphate bait or nighttime handpicking.

Harvest

Cut outer stalks as needed once they're 8+ inches tall, or harvest the whole head by cutting at the base. Celery doesn't store on the plant well in heat — harvest before hot weather hits. The leaves are edible and stronger-flavored than the stalks; dry them for a homemade celery salt.

Nerdy fact: Celery's famous 'negative calories' claim is a myth — but it does take a surprising amount of energy to chew and digest all that cellulose. More interesting: wild celery (smallage) was a bitter marsh plant, and it took centuries of breeding to get the crisp mild stalks we know. You're eating a domesticated swamp weed.

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