🥔 Mars Celeriac
What it looks like
Why this variety
Mars is a celeriac variety listed among the standard types, producing large, round roots with a sweet, mild flavor in about 120 days — a maincrop type for gardeners who want size without sacrificing sweetness. It is the kind of variety that does not need a story: big root, mild flavor, reliable season, done.
Use it for the full celeriac repertoire: remoulade, mash, soup, roast. Large roots are an advantage in the kitchen, not just the garden — one Mars root can carry a family mash, where smaller types take two or three and twice the peeling.
If you are new to choosing between cultivars, the Varieties Matter guide explains why the name after the plant matters as much as the plant itself. And if you want the whole clan at a glance, the broader Celeriac guide covers celeriac generally.
How to grow
Grow as a Florida fall-and-winter crop, best in the north, starting indoors 10 to 12 weeks before transplanting and setting out in fall. Rich, moist soil with plenty of compost, consistent water, and mulch are the requirements; a dry or poor bed gives small, cracked roots no matter how good the variety name sounds.
Space as listed, transplant carefully, and protect young plants from prolonged cold to avoid bolting. Mars wants a full, cool season — do not rush it, and do not leave it into summer heat either.
Water & feeding
Consistent moisture and mulch, with steady compost feeding through the season. Celeriac is a long-season, thirsty crop; uneven watering shows up as cracks, and cracks show up as waste.
Common problems
Bolting from cold, leaf miner, slugs, and cracking from uneven water. All are managed by timing, mulch, and steady watering. A large root that cracks is still edible — peel generously and use it in soup, where appearance does not matter.
Harvest
Harvest in winter when roots are large, round, and firm. Trim, store cool and moist, and use over weeks — Mars keeps well, which is part of why large-rooted celeriacs are winter staples rather than summer novelties.
Nerdy fact: Celeriac’s knobbly appearance hides a secret: under the rough skin is some of the smoothest, whitest flesh in the root world, which is why chefs love it for purees — the ugliest root in the bed makes the silkiest mash on the plate.
Saving seeds
Mars is a celeriac variety listed among the standard types, producing large, round roots with a sweet, mild flavor in about 120 days — a maincrop type for gardeners who want size without sacrificing sweetness. It is open-pollinated — Weseeds states it plainly, “Open pollinated, it produces seed that grows true to variety, ideal for seed saving” — so saved seed comes true to the big, mild roots. Let a few plants overwinter and flower in their second year, collect the seed once dry, and start indoors 10 to 12 weeks before transplanting in fall. The full method is in the Saving seeds section of the Celeriac guide.