Growing Parsnips on an Allotment

Parsnips are a slow-growing but very rewarding root crop, prized for their sweet flavour after frost. They need patience and good soil preparation, but once established they’re low maintenance and ideal for overwinter harvests. Parsnips are traditionally grown from seed, though plug plants can help with tricky germination.

This guide explains how to grow parsnips successfully, when to plant, spacing, watering and feeding, pests and diseases, container vs ground growing, and proven ways to improve yields.

🌱 1. Types of Parsnips You Can Grow

🥕 Long-rooted Parsnips

• Traditional shape

• Best flavour and storage

• Need deep, stone-free soil

🥕 Short & Stump Varieties

• More reliable in heavier soil

• Ideal for containers and raised beds

🥕 Exhibition / Giant Types

• Grown for size rather than flavour

• Require excellent soil and space

🌰 2. Ways to Grow Parsnips

From Seed (Most Common)

Pros

• Best root shape

• Cheapest option

• Widely available varieties

Cons

• Slow and unreliable germination

• Fresh seed essential

Plug Plants

Young parsnips grown in deep modules.

Pros

• More reliable establishment

• Useful where germination fails

• Faster early growth

Cons

• More expensive

• Limited availability

👉 Fresh seed, soil preparation, and moisture control matter more than starting method.

🗓️ 3. When to Sow & Plant Parsnips

From Seed

• Outdoors: February–April

• Best time: March (soil warming but still moist)

Plug Plants

• Plant out: March–May

Parsnips need a long growing season — sow as early as conditions allow.

🌾 4. How to Grow Parsnips in the Ground

Soil Requirements (Critical)

• Deep, stone-free soil

• Light and free-draining

• Not freshly manured

Fresh manure causes forked and misshapen roots.

Spacing

• Thin to: 15–20cm between plants

• Rows: 30–45cm apart

Crowded parsnips stay thin and short.

Sowing Depth

• Sow seeds 1–2cm deep

• Water gently and keep moist

• Germination can take 3–4 weeks

Many growers mark rows with fast-germinating radish seeds.

🪴 5. Growing Parsnips in Containers

Parsnips grow well in deep containers.

Container Guidelines

• Depth: 30–45cm minimum

• Use stone-free compost

• Choose short varieties

Containers are excellent for poor soil or pest control.

💧 6. Watering Parsnips

Parsnips need even moisture, especially early on.

Best Practice

• Keep seedbed moist until germination

• Water during long dry spells

• Avoid waterlogging

Irregular watering causes:

• woody roots

• slow growth

🌿 7. Feeding Parsnips

Parsnips are light feeders.

Feeding Rules

• Compost before sowing is enough

• Avoid nitrogen-rich fertilisers

• Optional light feed if growth stalls

Too much feed = leafy tops, poor roots.

🐛 8. Common Pests & Diseases

Carrot Fly

Symptoms

• Red or purple leaves

• Rusty tunnels in roots

Prevention

• Fine mesh barriers

• Avoid thinning during the day

• Grow in containers

Parsnip Canker

Symptoms

• Brown sunken patches on roots

Prevention

• Avoid waterlogging

• Practice crop rotation

• Harvest carefully

Slugs

• Damage young seedlings

Protect seedlings early.

🧺 9. Harvesting Parsnips

When to Harvest

• From late autumn onwards

• Best flavour after frost

Parsnips can remain in the ground throughout winter.

How to Harvest

• Loosen soil gently

• Lift carefully to avoid snapping

Harvest as needed — roots store best in the ground.

🌾 10. Improving Parsnip Yields

• Use fresh seed every year

• Prepare soil thoroughly

• Sow early

• Keep moisture consistent

• Thin properly

Parsnips reward patience, not feeding.

⚡ Quick Parsnip Growing Tips

• Never use fresh manure

• Don’t rush germination — be patient

• Frost improves flavour

• Use deep containers if soil is poor

🧠 Key Parsnip Principles

• Soil depth matters most

• Fresh seed is essential

• Even moisture improves quality

• Frost improves flavour