Thomson

Family: Apiaceae Root Vegetable

Aromatically bold from the first peel, Thomson celeriac offers a deeply celery-scented, nutty-sweet flavor with a firm, creamy interior that stays pleasantly dense.

Its knobby, turnip-like form develops into a smooth, pale flesh with a clean bite and a refined, savory character—ideal for roasting, braising, and velvety purées, as well as pickling for a tangy crunch. For gardeners who love roots with personality, Thomson delivers dependable harvests around 100 days with a striking, harvest-ready silhouette.

Light: Part SunMaturity: 100 DaysHabit: Upright

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

Milestone	Date
Start Indoors	Feb 14th
Last Frost	Apr 25th
Transplant / Sow Outdoors	Apr 18th
Harvest Begins	Jul 27th
Harvest Ends	Oct 16th

Crop Details

Trait	Value
Days to Maturity	100
Sun Requirements	Part Sun
Growth Habit	Upright
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	70
Min Soil Temp (°F)	45
Min Night Temp (°F)	28
Harden Off (days)	6

Culinary Notes

Chef's Note

Thomson celeriac is a root with actual presence—its celery-strong perfume comes through even after heat, and the interior stays dense rather than collapsing into mush. It purées like cashmere but still slices clean for roasting or pickling, making it a go-to for dishes that need a fragrant, savory backbone.

Best Uses

roasted wedges with browned edges for a nutty, concentrated bite
braised or stewed into silky chunks that don’t turn watery
velvety purée with butter/cream for a refined spoonable texture
quick pickling for a tangy, snappy crunch

Flavor Profile

deep celery-scented aroma nutty-sweet, savory finish firm yet creamy interior clean, dense bite that holds up to heat

Kitchen Pairings

butter heavy cream lemon black pepper mushrooms pork

Frequently Asked Questions

What pest or disease most commonly affects celeriac (Apium graveolens var. rapaceum), and how can I treat it?

Celeriac commonly suffers from celery leaf spot and other leaf blights (often starting as small brown-to-black spots on leaves in humid weather). Remove infected leaves early and water at the base to keep foliage dry; for ongoing trouble, use a labeled fungicide targeted to leaf spots per the product label. Check plants regularly after rains and space them well for airflow so leaves dry faster.

How often should I water celeriac during the main growing phase, and what soil moisture level should I maintain?

During the main growth period (roughly from established seedlings until bulbing forms), keep soil consistently evenly moist—aim for the top few inches to stay damp but never waterlogged. Water deeply about 1–2 times per week depending on heat and rainfall, and increase frequency during dry spells so the growing “swollen root” develops without cracking or hollow texture. If the soil dries out too much, celeriac can become woody and bitter.

How do I tell when celeriac is ready to harvest?

Harvest when the celeriac bulb has filled out to a usable size and the outer surface feels firm, typically around 100 days from sowing for your variety. Leaves may still be green, but you should see a clearly formed, sturdy knob with no soft spots. For best flavor, lift before hard frosts, and if you must wait, protect plants lightly during cold spells rather than letting the bulb turn soft.