This delicious, hardy winter vegetable develops its sweet, nutty flavour when cold temperatures turn the starches in the root to sugar, so traditionally the first parsnips are only lifted after a hard frost. If you do harvest parsnips before a frost, bag them up and keep them in the fridge for two weeks to sweeten the roots.
Parsnips are easy to grow members of the cow parsley family. This family includes carrot, dill, fennel and parsley among others. These seeds tend to have a short period of viability, so new packets of seed should be purchased every year. This family also need warm temperatures to germinate and the air temperature has to reach 12C (52F) before germination occurs. Wait for spring to arrive before you sow any of them. However seeds should be acquired now because this vegetable regularly heads the top ten seeds list and it often disappears off the shelves early on.
Wait for April to sow
Parsnips are slow to germinate and you are much more likely to succeed with growing them if you wait until April before sowing the seeds. Ignore the advice on the packets, which usually recommends February sowing. The temperatures then are too cool and this leads to crop failure. I think this 'February sowing' myth has come about because parsnip seeds take a minimum of 30 days before they appear. So seed companies want you to get seedlings up by March - an impossibility in most years.
The sowing technique
I use a wide four-inch drill and scatter the seeds along: this gives the roots plenty of space to develop without thinning out at the seedling stage. Some people recommend station sowing, ie leaving six-inch gaps between clusters of seeds. I find this doesn’t work as parsnip germination can be patchy, so you often get wide gaps without any roots.
1. Choose a still day because parsnip seeds are very light and papery and they can blow away as you handle them
2. Dig the area deeply and then use a line to mark the row before raking out a wide four-inch drill.
3. Water the drill - this will fix the seeds in position.
4. Sow the seeds to a depth of half of an inch and then lightly cover with soil.
5. Protect with chicken wire to prevent cats and birds from scratching the seeds up.
6. If sowing two rows position them a foot apart (30 cm/12 in)
7. Water the seeds in dry weather and keep the drills weed free.
Parsnips enjoy well-drained, finely-grained soil. If your allotment has heavy or stony soil soil opt for a short-rooted variety. There are traditional varieties and newer hybrids. Today the latter are more popular, although the seeds are more costly to produce.
Parsnips have undergone a change within the last thirty years because there are now F1 hybrid varieties. These are very smooth skinned so they shrug off diseases like canker. They tend to have flat crowns so they don’t get crown rot like some older varieties with dished tops.
Good disease resistance - uniform shape. Hybrids germinate more willingly and that alone makes them worth growing.
Hybrid F1 Varieties
The original hybrid (bred in 1982 by Tozer Seeds) with smooth, silky skin and large wedge-shaped roots. Canker resistant and widely available
A newer variety from Tozer Seeds with white, tapering roots and smooth blemish-free skin. Strong germination and a vigorous, uniform grower.
Very white-skinned roots with creamy flesh of sweet flavour. With good tolerance against canker and shallow crowns.
The best seller commercially due to its uniform shape. A shorter-rooted variety.
A gardener’s favourite due to its high crown, smooth skin and tender roots. Good canker resistance
White-skinned, conical roots with shallow crowns and an excellent flavour. Ideal used as a maincrop variety for lifting between October through to April.
'Tender and True'
Long roots and a good flavour with good canker resistance. Not as silkily skinned.
Parsnips are very hardy and they can be left in the ground until April. This makes them well worth growing for winter use, because you dig them as you use them.
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