Celeriac is a cool-season root crop grown for its knobby, celery-flavored root. The University of Arkansas guide lists about 200 days from seeding to maturity, so it needs a long, cool season and an early start. This page covers seed starting, spacing, watering and harvest.
Celeriac at a glance
| Type | Vegetable |
|---|---|
| Season | Cool-season |
| Sun | Full sun |
| Plant spacing | 6 in |
| Row spacing | 20 in |
| Per square foot | 4 |
| Seed depth | ¼ in |
| Days to maturity | 100–200 from seed |
| How to start | Sow seed in early spring in a cold frame or indoors, 4 to 6 weeks before transplanting. |
| Water | 1.5 in per week |
These are the same numbers our plant spacing, square foot and harvest date calculators use. See every crop in the plant database.
When to plant celeriac
Sow seed in early spring in a cold frame or indoors, 4 to 6 weeks before transplanting. Seed is sown 1/4 inch deep and germination can take 21 days or more. Transplant when seedlings are 2 to 2.5 inches tall. Use the frost dates by ZIP code and planting calendar.
How to plant celeriac
- Choose full sun and well-drained loam, pH 5.8 to 6.5, of medium fertility.
- Space 6 inches apart in rows 18 to 24 inches wide; use the plant spacing calculator.
- Give a starter solution at establishment.
Caring for celeriac
Keep the soil moist and water evenly during drought; interruptions in growth greatly reduce root size. See the garden watering calculator. Feed monthly.
Companion plants
| Grow nearby | Other cool-season vegetables such as leeks and cabbage family crops |
|---|---|
| Keep apart | Dry, hot sites |
The Arkansas guide says stems and leaves are generally free from pests. Check other pairings with the companion plant finder.
Common problems
| Problem | What you see | What to do |
|---|---|---|
| Small roots | Roots that stay small | Uneven water slows growth. Keep soil moist and water evenly during drought. |
| Slow germination | Seed that takes weeks to sprout | Germination can take 21 days or more, so be patient and keep the seed tray moist. |
Not sure what you are looking at? The plant problem identifier ranks likely causes from the symptoms you see.
When and how to harvest
Roots can be harvested when about baseball-sized, or 3 to 4 inches across for best quality. Flavor peaks after the first fall frost. Mulching with straw or leaves allows winter harvest. Expect more than 1 pound of usable root per foot of row.
Plan your celeriac
- Plant spacing calculator: how many plants fit your bed
- Planting calendar: sowing and transplant dates for your frost dates
- Frost dates by ZIP code: your last spring and first fall frost
- Harvest date calculator: when your crop will be ready
Frequently asked questions
How far apart should I plant celeriac plants?
Space celeriac plants 6 inches apart in rows 20 inches apart. In a square foot garden, plant 4 per square foot.
How deep do I plant celeriac seeds?
Sow celeriac seed 1/4 inch deep and transplant seedlings at 2 to 2.5 inches tall, 6 inches apart.
How long do celeriac plants take to grow?
Celeriac takes about 200 days from seeding; some cultivars are listed from 100 to 115 days.
How much water do celeriac plants need?
About 1.5 inches of water a week, from rain and watering combined. Keep soil moist and water evenly, especially in drought.
When do I harvest celeriac?
When roots are 3 to 4 inches across; flavor peaks after the first fall frost.
Can I harvest celeriac in winter?
Yes, mulch with straw or leaves to allow winter harvest.
Why is my celeriac small?
Interrupted growth, often from uneven watering, greatly reduces root size.