Roots & tubers
Celeriac
Long season.
- Indoors
- 10 wk (Feb)
- Outside
- Transplant mid May
- Where
- Raised bed or in ground, rich soil
- Sun
- Full sun
- Water
- Never dry; a parched week marks the root
- Harvest
- Oct to Nov, better after frost
Care
- Water
- Never dry, not even for a week; a single parched stretch in July still shows up in the autumn root. Give rich soil a deep, even soak once or twice a week, every 3 to 4 days in July heat, judged by the finger test. This long-season root tolerates a lot, but never drought.
- Sow
- Several seeds per cell indoors, thinned to the strongest after 2 true leaves. Set transplants 8 inches apart, in rows 2 to 3 feet apart, in rich soil in mid May. Through late summer, pull off the outer leaves and side shoots so the knob rounds cleanly.
- Start inside
- Mat at 70 to 75F and barely cover the seed, an eighth of an inch, since it needs light to germinate. Sprouts are slow, 2 to 3 weeks, and half coming up is a good stand. Under the lights at emergence, then ease to 60 to 70F. Out in mid May, once frost is past.
- Feed
- A long-season root that wants steady fertility. A shovel of compost or castings dug into rich soil at transplant, then a top-dress of slow-release organic fertilizer every month through summer. A little fish and seaweed liquid is welcome here, unusually for a root, given the length of the haul.
- Ready
- Dig from October well into November, about 110 to 130 days along; a light frost or two only sweetens it. Lift the whole knob with a fork, trim the roots and tops, and it keeps in a fridge drawer for months.
- Trouble
- An early flower stalk: cold-snap vernalization, which this crop triggers from more readily than any relative, so the cautious mid-May transplant is on purpose. Weak, hopeless-looking seedlings early on: normal for this slow crop, not disease; they come good once settled.
In a bag?
- Yes
- Up to a 7–10 gal bag.
- Water
- Daily through summer, and never let it dry, which a bag makes harder; 45 to 60 sec on the shower dial until it runs from the seams.
- Feed
- Top-dress monthly; every watering leaches the bag over its long season.
- Sow
- One plant per bag.
Celeriac is the garden's longest appointment: sown indoors in February, transplanted in May, dug at the end of October. The knobbly root that patience buys is the best soup vegetable on the card.
Growing
Sow in February, a good ten weeks ahead, and accept that the seedlings look doomed for their first month; tiny and slow is the breed. Transplant once frost is past in mid May into rich soil a foot apart, and keep the bed moist without fail; one parched week in July is still legible in the root you dig in October. In late summer, strip the outer leaves and any side shoots so the crown grows smooth. Dig from October into November; light frost improves it, and a fridge drawer holds roots for months.
Varieties
Brilliant is the smooth modern standard; Prinz stays dense and stores well.
In the kitchen
Remoulade if it stays raw, and a silk-textured soup with nothing but potato and onion if it does not. Half celeriac in the mash quietly upgrades a roast dinner.