How to grow parsnip
Overview
Parsnip is a slow-maturing root vegetable of the Apiaceae family, prized for its sweet, nutty flavour that develops after frost. It requires deep, well-prepared soil and fresh seed for reliable germination.
Varieties
- Hollow Crown — An heirloom variety with excellent flavour and long, smooth roots, widely grown in Australia.
- Harris Model — A popular modern variety with high yield, good disease resistance, and uniform roots.
Soil Preparation
Parsnip needs deep, loose, well-drained soil free of stones and clods for straight roots. Ideal pH is 6.0–6.8. Dig soil to 30 cm depth and remove all debris; add well-rotted compost but no fresh manure.
Growing Guide
Sow parsnip seed directly into deep, stone-free soil at 1 cm depth, spacing seeds 5 cm apart and thinning to 10 cm. Keep soil consistently moist during the long germination period (2–4 weeks). Full sun is essential, and avoid transplanting as taproots are easily damaged. In warm zones, time sowing so roots mature in cooler weather for best sweetness.
Sowing
Sow fresh seed (viability drops after 1 year) 1 cm deep, 5 cm apart, in rows 30 cm apart. Germination takes 2–4 weeks; keep soil moist. Direct sowing is essential as taproots do not transplant well.
Care
Feed with a low-nitrogen fertiliser (e.g., seaweed or tomato feed) once seedlings are 10 cm tall to discourage forking. Keep soil weed-free by shallow hoeing, and water evenly to prevent cracking.
Companion Planting
Plant parsnip with onion, lettuce, and peas. Avoid growing near carrots (to prevent cross-pollination and shared pests) or in soil recently manured for other crops, which can cause forked roots.
Common Pests & Risks
Carrot fly (rust fly) is the main pest: its larvae tunnel into roots. Use fine mesh netting or plant near onions to deter. Aphids on foliage can be hosed off; avoid overwatering to prevent root rot in heavy soils.
Harvesting
Harvest parsnips after roots reach 2–3 cm diameter at the crown, typically 4–6 months after sowing. Flavour improves after a light frost; lift with a fork to avoid breaking the taproot. Store in damp sand in a cool place for months.
In the Kitchen
Peel parsnips before cooking; they can be roasted, boiled, or mashed. Their sweetness intensifies after frost, making them ideal in winter soups and stews. Store in a cool, dark place for up to 3 months.
Troubleshooting
Seeds fail to germinate: use fresh seed each year; old seed is unreliable. Forked roots: caused by stones or heavy soil; prepare deep, fine soil. Brown leaf edges: often due to inconsistent watering; keep soil evenly moist. Small roots: overcrowding or poor soil; thin to 10 cm apart. Bitter taste: harvest before frost; cold improves sweetness.