Description

The Underground Treasure, Central European Heritage and the Celeriac of Magnificent Abundance

Giant Prague celeriac is the kind of root that feels like a secret. It’s like a treasure you only understand once you lift it from the soil.

Above ground, celeriac looks like a lush, celery-green bouquet with its sturdy stems and  bright leaves. It is a plant that seems almost ornamental in its vigour. But beneath the surface, it is building something slow and magnificent. It has a warm golden-brown bulb, heavy in the hand, knobbled and earthy on the outside and pale, fragrant, and creamy within. When you peel it, the scent is unmistakable: celery and parsley and something more profound, almost nutty. Slice it raw, and it snaps clean. Cook it, and it turns velvety, rich, and comforting. It’s a winter flavour grown from summer patience.

A whisper of history

Celeriac traces its lineage to wild celery relatives of the Mediterranean. Over centuries, European gardeners selected celery not only for its leaves and stalks, but also for plants that formed enlarged, tender roots.

Giant Prague is a classic Central European selection, valued for its impressive size and dependable performance: a variety bred to make the most of a season, producing substantial roots that store beautifully and feed you well into winter.

What You’ll Grow

• Plant type: Cool-season root crop (celery family)
• Plant size: typically 30 to 45 cm (12 to 18 in) tall and wide
• Root type: large, bulbous celeriac (celery root)
• Root size: typically 10 to 15 cm (4 to 6 in) across (often larger with good care)
• Skin: golden-brown, earthy
• Flesh: pale, firm, aromatic
• Texture: crisp raw; creamy and tender when cooked
• Flavour: complex, celery-like with a gentle parsley/nutty depth

Days to maturity: typically 120 to 150 days from sowing (long season).

Growing Instructions

Celeriac is a long-season crop that rewards early starts, steady moisture, and consistent feeding. Think of it like a slow-building root that hates stress and loves routine.

When to Start

• Start seeds indoors 8 to 10 weeks before the last frost
• Plan for a long season: celeriac needs time to size up

Starting from Seed (Indoors)

• Sow very shallowly, about 3 to 6 mm (1/8 to 1/4 in) deep (or press into the surface and lightly cover)
• Keep evenly moist (not soggy)
• Provide bright light once seedlings emerge

Germination: typically 14 to 21 days at 18 to 24C (65 to 75F).

Seedling Care (Slow Start, Strong Finish)

• Celeriac seedlings can be slow; keep temps steady and don’t let trays dry out
• Pot up if seedlings outgrow cells before transplant time

Hardening Off

• Harden off over 7 to 10 days before transplanting

Transplanting

• Transplant after danger of hard frost when seedlings have 4 to 6 true leaves
• Space plants 30 to 45 cm (12 to 18 in) apart
• Space rows 45 to 60 cm (18 to 24 in) apart

Soil + Site

• Full sun is best (6 to 8+ hours)
• Soil should be fertile, well-drained, and rich in organic matter
• Target pH 6.0 to 7.0

Before planting:

• Work in compost or well-rotted manure
• Celeriac is a heavy feeder; steady fertility supports big, dense roots

Watering (Non-Negotiable for Size + Tenderness)

• Aim for 2.5 to 5 cm (1 to 2 in) of water per week
• Keep moisture consistent; drought stress leads to stringy texture and smaller roots
• Mulch to conserve moisture and moderate soil temperature

Feeding

• Side-dress with compost or a balanced fertilizer every 3 to 4 weeks during active growth
• Avoid boom-and-bust feeding; steady nutrition builds steady roots

Weed Control

• Keep beds weeded, as celeriac dislikes competition

Leaf + Root Management (Optional but Helpful)

• As the bulb begins to swell, you can remove a few outer leaves to improve airflow and encourage energy into the root
• Keep the crown area reasonably clear; avoid damaging the bulb

Pest Notes

• Watch for celery leaf miner, aphids, and general garden chew damage
• Row cover early can help reduce pest pressure

Harvesting (The Moment the Treasure Surfaces)

• Harvest when roots are 10 to 15 cm (4 to 6 in) across and feel heavy and firm
• Dig carefully with a fork; loosen soil before lifting to avoid tearing

Celeriac can handle cool weather and often tastes even better after light frosts.

Preserving + Storage

Giant Prague is made for storage.

• Store at 0 to 4C (32 to 40F) with high humidity for several months
• Trim tops, leaving a short stub
• Store in a perforated bag, or layer in damp sand/sawdust to prevent shrivelling

Preserving options:

• Freeze: blanch cubes for soups and stews
• Pickle: crisp, aromatic chunks in brine
• Ferment: for a tangy, savoury preserve

Culinary Notes: Celery-Sweet, Earthy, and Deeply Comforting

Celeriac is a chef’s root, complex, aromatic, and endlessly useful.

• Raw: julienned for classic celeriac remoulade; crisp and fragrant
• Roasted: caramelized edges, nutty sweetness
• Mashed: creamy, savoury alternative to potatoes
• Soups + stews: depth and body with a celery-like perfume
• Purees: silky and elegant under fish or roast vegetables
• Chips: thin-sliced and baked/fried for a crunchy snack

Prep Tip

• Peel just before using to prevent browning
• Roast at 400 to 425°F for 30 to 40 minutes for peak caramelization

Canadian Climate Notes

Celeriac is a cool-season, long-season crop, and Canada can grow it beautifully when you start early.

• Start indoors early (8 to 10 weeks before last frost)
• Transplant once weather settles; keep growth steady with water + feeding
• Plan for fall harvest and winter storage

Growing zones: 2 to 10 (annual; cool-season crop).

Seed Saving

Celeriac is biennial for seed.

How to Save Seed (High-Level)

1. In the fall, select the best roots (largest, best shape, best flavour)
2. Overwinter roots (in-ground only where winters are mild; otherwise store cool and humid)
3. Replant in spring; plants flower and set seed in umbels
4. Let seed heads dry on the plant, then harvest and finish drying indoors
5. Rub/thresh to release seed; store cool, dark, and dry

Isolation & Cross-Pollination

• Celeriac can cross with other celeriac/celery types and wild celery relatives
• For pure seed, isolate by distance as practically, or only let one type flower

Seed viability: typically 3 to 4 years

Giant Prague is the underground treasure, a Central European heirloom that turns patience into abundance, and a single root into a season’s worth of comfort.