HOW TO GROW PARSNIPS
By David Marks
Parsnips are one of the few select group of vegetables which can provide a crop during the bleak winter months. For that reason alone they are worth growing, there is something undeniably satisfying about growing your own winter food.
They have a definite advantage over carrots because they are far les prone to disease. Pull a parsnip up in winter and you have a very good chance that it will be unaffected by pests or disease.
TYPES OF PARSNIP
There are no real "types" of parsnips but there definitely are varieties which are better for some soils compared to others. All parsnips are best suited to well dug, light soil which drains well. However some varieties do better on heavy soils such as clay. These are the thicker types which are also shorter. One common example of this variety is White Gem – it will never win any prizes at the show bench but if your soil is heavy then this makes an excellent choice.
Our list of suggested varieties, which can be seen here, gives extensive details
of all the easily obtained parsnip varieties in the UK and Ireland.
Before reading this article further why not take two minutes to adjust all the dates in this website (including those below) to be more accurate for your home town (both UK and Ireland). The dates will default to the UK average if no dates are set. The settings will last for six months or more.
QUICK CALENDAR FOR GROWING PARSNIPS IN THE
Pre-germinate parsnip seeds (optional) – April week 3
Sow parsnip seeds outside - April week 4
Thin parsnip seedlings - May week 4
Begin to harvest parsnips - September week 2
Parsnips grow best in the following conditions:
- A well-drained soil which has been well dug to include lots of
well-rotted organic material.
- Remove as many stones from the ground as possible. When parsnip roots hit stones they tend to
split and grow wonky.
- Do not add manure to the site before sowing seed. Addition of fresh manure encourages the roots to split
- Parsnips prefer a neutral to slightly alkaline soil. They don't do well on acid soils. See here
for more about soil acidity / alkalinity.
- They grow equally well in full sun and partial shade. They don't like dry soil however so if that might be a problem on your plot position them in partial shade where the soil will remain moist for longer.
Firstly to practical matters, parsnip seeds are wafer thin and very light, so only sow them when
there is no wind. The seeds only last six months or so and definitely not for a year, so choose
your supplier carefully. Sowing old parsnip seeds will only result in disappointment.
One word of hard-earned advice, forget sowing parsnip seeds in pots or loo roll inners, it doesn't work well. The plants will come up successfully but the roots inevitably will be forked. This applies to sowing directly in the ground and pre-germinating the seeds first.
Follow our advice below for sowing parsnip seed directly in the ground and you should have no problems. If you want to sow the seeds directly in the ground outside without pre-germinating them click here to skip the next section.
Parsnips are notoriously difficult to germinate so you may want to pre-germinate the seeds before sowing them. Pre-germinating seed starts them into life before you sow them which is especially useful with parsnips.
The steps for pre-germinating parsnip seed are simple and outlined below:
- Start the process off in
the third week of April
which is a week or so before you would normally sow the seed directly outside.
- Place the seeds on a damp paper towel in a bowl or container and gently pat them down. Cover with
cling film to prevent moisture loss (the cling film should not be touching the seeds) and place in a
moderately warm area inside the house, a temperature of around 60°F to 70°F (15°C to
21°C) is ideal.
- Keep the paper towel moist at all times. The seeds will take seven to ten days to germinate, if
they haven't geminated after three weeks using this method then suspect that they never will. In this case
buy new fresh seeds from a reputable supplier and start the process again.
- Germinated seeds will sprout a tiny white root which indicates they are beginning to grow. The
roots are difficult to see on white paper towels so keep a good watch on them at least once a day
after the first three days.
- Immediately the seeds have germinated, sow them as described below. It will be a bit fiddly to do this because the seeds will be damp. The best solution is to take the paper towel with the pre-germinated seeds outside to where they can be sown one by one.
As long as you stick to the timescales below you should have no problem getting parsnips to grow from a direct outdoor sowing. The key is to ignore any advice which suggests sowing the seeds as early as possible in the year, even if it appears on the seed packet.
Parsnip seeds need a minimum soil temperature of 41°F / 5°C to germinate but the ideal temperature attainable in the UK is about 53°F / 12°C which occurs most years in the last week of April. Stick to that date, ignore any advice about earlier dates and you won't go far wrong.
Use the edge of a hoe or a trowel to draw a groove in the prepared soil to a depth of 2.5cm / 1in. Sow one seed every 5cm / 2in, if you have more than one row the rows should be 45cm / 18in apart. Draw the soil over the seeds and water well.
The seeds will take a couple of weeks to appear above ground, longer in some cases, so make sure you mark the rows carefully to indicate where they are sown. A line of string will do fine. Some gardeners sow radish seed along side the rows which does two things. First, the radish seedlings will appear much sooner than the parsnip seedlings which will clearly show where the parsnips are. It will also give you a crop of radish well before they are able to interfere with the parsnips.
When the seedlings appear thin them to one every 20cm / 8in apart. Throw the thinnings on the compost heap, don't replant them elsewhere because replanted parsnips do not grow well.
Parsnips develop long tap roots so they are unlikely to die from lack of water. Watering in dry conditions however, will help stop the roots from splitting.
Parsnips grow best where nitrogen based nutrients are slightly on the low side. We suggest a feed of blood, fish and bone fertiliser every other month to provide trace elements and other nutrients.
Your parsnips will look after themselves from now on until harvest time, regular weeding is the only job required.
Your parsnips will be large enough to harvest from mid-September onwards and will last in the ground until early the next year. Traditional gardening wisdom says that parsnips exposed to frosts sweeten up and taste better than those harvested earlier. Conduct your own taste experiment by harvesting some in mid September and then in early November comparing the taste of the two.
Parsnips store best when left in the ground but in cooler areas, from October onwards, frozen soil can make harvesting near impossible. Harvested parsnips can be stored in buckets of garden soil or spent compost in a garden shed or unheated garage.
One word of advice for those who plan leave their parsnips in the ground from late October onwards, is that the foliage dies down and in some cases it is difficult to see exactly where your remaining parsnips are! We recommend some form of marking them – plant labels or a line of string are two obvious solutions.
Click here for our page dedicated to the different varieties of parsnips which are available in the UK and Ireland.
You may also like our in depth articles on:
COMMENTS / QUESTIONS LEFT BY OUR READERS
|Date: 06 March 2017
|From: Rhys J
|I had the best best crop yet last year sowing on the spring equinox and covering the sown area with
fleece until the end of April. Despite the cool April in NW London, germination was excellent. Seeds were Tender and True.
|Date: 08 February 2017
|From: Peter M
|After germinating my parsnips in damp fine compost I place them in a fine seive and wash them very
gently under tepid water. I use agar jelly made very thinly to fluid sow my seed which also has radish mixed in. Agar
jelly (as used in cooking ) is glass clear and it is easy see your seeds and place them in exact position. I do this
with other seeds as well. Failure is very rare. Agar is from seaweed and contains no nasty stuff and in fact is
edible and sterile.
|Date: 24 May 2016
|I pre germinate my parsnips seeds in a small zip lock bag with a little damp compost. When they grow
small tales (about 1/2″ long I use a old teaspoon to scoop under the sprouted seeds and plant in a shallow drill about
8″ apart and cover the sprouted seedlings with a trickle of fine compost or coir. Works every time for me I been doing
it this method for many years,