I suppose you could take them before there’s been a frost if you wanted to — it’s not an arrestable offence as far as I know — but conventional wisdom has it that their full flavour doesn’t develop until they’ve been chilled.
Like most gardeners, I’ve no idea whether that is actually true, because I’ve never eaten them pre-frost.
And while we’re at it, I should mention that you don’t have to lift your parsnips for months yet. They’ll usually keep in the soil perfectly well right through the winter.
Of course, a lot of keen vegetable gardeners won’t be lifting any parsnips, either now or later, because they didn’t sow any.
Snips have a reputation for being difficult to grow, but I don’t think that’s true. What they can certainly be is difficult to germinate.
Once you’ve got the seedlings growing away strongly, parsnips need very little further attention.
There are a number of things you can do to maximise the chance of success in the early, tricky stage of a young snip’s life.
First of all, be aware that parsnip seeds have an unusually brief shelf life.
The seeds of most popular vegetables will retain reasonable germination rates for a couple of years, even from an opened packet, and some will last much longer.
But parsnip is one of the main exceptions, and you should really start every year with a newly bought supply.
The second necessity is patience. Most gardening books, even today, recommend that parsnips should be sown as early as possible at winter’s end.
As we all know, “The tradition of past generations weighs like an Alp on the brains of the living” and this is an example of handed-down knowledge which generations of gardeners have forgotten to test.
I suspect it dates back to the days when a root vegetable wasn’t thought worth digging up unless it was at least the size of an undergardener’s thigh, so needed as long a growing period as possible.
In fact, like most garden crops, parsnip is unlikely to germinate well in soil that is cold, sodden and airless.
I don’t start mine off before mid-April, and they always produce plenty of flesh for Christmas.
Another piece of inherited information about parsnips, which may have been true in the past, is that they can’t be transplanted.
Advances in seed-sowing equipment available to the home gardener in recent decades have rendered this advice outdated.
Transplanting works perfectly well, provided you’re using root-trainers, or cellular trays, which allow you to plant out the seedlings without disturbing their roots.
This means you can start the seeds under cover, such as in a cold greenhouse, where they’ll be protected from slugs and weather.
Once the seedlings are well established, plant them outside at at least nine inches apart each way. That gives you room to dig them up in winter.