I use a rating system to help me decide what to grow and it considers lots of factors, but the main ones are how tasty it is, how healthy it is to eat, how expensive it is to buy, how big it's harvest is, when it's harvest period is and whether I can buy it organically and if not how much it's sprayed.
Parsnips score extremely poorly in this system. They are tasty but not exceptionally so, they are extremely cheap to buy, the yield is low and can be unpredictable. They take a very long time to grow and they grow at the prime time of year (spring and summer) and then take up ground until harvested.
Why grow them then? Well they provide a harvest at a time when veg is in shorter supply, i.e. all through winter and they are hard to find organically, because they are usually sprayed or otherwise treated for carrot root fly when grown commercially and are too low value for most organic farmers to bother.
<aside> 💡 Of course, people grow them for the fun of it and because they are popular to show, I grow to eat though so for me they are only worth growing because of the inability to get organically AND because I interplant them with onions to increase the harvest value. I also grow them late, so I can at least get my spring harvest from the same ground
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Parsnips are another easy one to estimate, I typically plant about 20/m2 which is a fairly low yield for such a low value crop, so I wouldn’t grow too many of them myself.
Parsnips are very deep rooted and don’t grow well in containers or stony soils, they grow really well in my stone free sandy soil though. They do benefit from full sun but tolerate light shade.
Many gardening books will stress the need for weed free soil to reduce competition, however I don’t have weed free soil (loads of marestail) so I just keep on top of weeding. I also interplant with good success.
Parsnips are sown in spring and go to seed the following spring. They are fairly slow to germinate, being sown direct in the soil, and grow very slowly for the first few months, which makes them a good option for interplanting.
Some people sow their parsnips very early, I’ve seen them do it in February and March. Sown this early two things are likely to happen, first the seeds will rot in the cold/wet soil and if they survive they will germinate VERY slowly and then grow very slowly. I don’t think it’s worth it, especially as I have winter and spring crops in the ground that I’m still harvesting in February, March and April. So with that bias clear, here’s what I recommend and what I’m experimenting with.
<aside> 💡 For more details on the model that I use for describing harvest periods (first earlies, second earlies etc) please see the chapter on my growing framework
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https://airtable.com/shrvpWZaRUswXXVMD
<aside> 💡 The video and text below document a very successful experiment in 2022
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