How to grow parsnips

Delicious roasted or added to hearty winter stews, parsnips are easy to grow, need little maintenance and can be left in the ground until you’re ready to eat them. Sow in spring and you’ll have sweet, tasty, home-grown parsnips by autumn – and for your Christmas dinner too.

A traditional and popular autumn and winter crop, parsnips are undemanding, low maintenance and a must for any veg grower, from beginners to experts. Although slow growing, these deliciously sweet, earthy roots are well worth the wait.

They should be sown direct into their growing position in spring, ideally in light, free-draining soil. Few pests trouble them, apart from carrot fly, which can be deterred with insect-proof mesh. Seed

Germination is the process by which a seed develops into a new plant. It starts with the seed coat absorbing water, expanding and splitting, which allows oxygen and water into the seed so its food reserves can be broken down and used by the embryo for growth. The first root (called the radicle) pushes into the soil to anchor the new plant in place and start absorbing water and nutrients. The first shoot (called the plumule) then grows upwards, out of the soil, towards the light.

Parsnips need little ongoing care, apart from weeding when young and watering in dry spells. The roots are ready to harvest from autumn onwards, although it’s best to delay until after the first hard frost for the sweetest flavour. They’re very hardy and can be left in the ground right through winter, to be dug up whenever needed, for a tasty home-grown treat.

There are several varieties to choose from, varying mainly in size and shape. Most form long, tapering roots, although a few are shorter and more bulbous, which is preferable if you have heavy, shallow or stony soil. Roots range in colour from cream to pure white, although all have a similar flavour.

It’s worth choosing a variety that is canker-resistant and has an RHS Award of Garden Merit (AGM), which means it should grow well and crop reliably – see our list of AGM fruit and veg.

Parsnips prefer an open, sunny site, with fertile, light soil that drains readily. Soil that has been improved with well-rotted manure or garden compost the previous season is ideal.

To help ensure long straight roots that don’t fork, remove as many stones as possible and loosen heavy clay or compacted soil, but don’t add any organic matter before sowing.

If the spring weather is cold and wet, cover the soil with a cloche or plastic sheeting a couple of weeks before sowing, to dry it out and warm it, as parsnip seeds don’t germinate well in cold, damp ground.

Parsnips have a reputation for being tricky to germinate, but if you wait until the soil has warmed up in mid-spring, use fresh seeds and sow plenty, you should have good results. Simply follow our tips.

Parsnips are ready to lift when the leaves start to die down in late summer or autumn. It’s a good idea to wait until after the first heavy frost though, as this intensifies their sweetness and flavour.

Make sure your crop is clearly marked with canes or labels before the leaves disappear, so the roots are easy to find in winter.

Use a garden fork to carefully ease the long roots out of the ground intact. If the soil is dry, watering first can make harvesting easier.

Parsnip roots are very hardy, so can be left in the ground into winter and harvested as required. Still, they can be difficult to harvest from frozen ground, so it may be worth lifting a few extra in November to ensure you have parsnips to enjoy however cold it gets. Alternatively, cover the ground with fleece or straw as insulation.

Parsnips are generally healthy and problem free, but seed germination can be poor and slow, especially in cold soil, so don’t sow too early. Always use fresh seeds and protect sowings with a cloche to keep them warm and aid germination.

Roots can fork in stony or compacted soil, or if manure or garden compost have been added recently. Roots can also split if growth is erratic, so water regularly in dry spells to avoid this.

Parsnips can suffer damage from carrot fly, so put protection in place early.

Parsnip canker (an orange/brown rot) can affect the roots, especially if damaged, in dry conditions or in overly rich soil. Resistant varieties (‘Avonresister’ and ‘Archer’) are available.