Growing parsnips: when, where & the best companion plants
Parsnips are a simple and popular root vegetable to grow. With a little know-how, you too can look forward to a delicious crop of juicy parsnips from October onwards. Discover all you need to know about growing parsnips, including when, where and how to sow parsnips.
The parsnip (Pastinaca sativa) is a very popular root vegetable and a close relative of the carrot (Daucus carota). The two root crops are also very similar to grow. Read on for all the answers on how to successfully grow parsnips, including location, sowing and companion planting.
When to sow parsnips?
Growing parsnips can be a lengthy process because the seeds are notoriously slow to germinate and they grow slowly. From sowing to harvesting, it can take anywhere between 160 and 200 days. This is dependent on the parsnip varieties and the weather. Therefore, if you are wondering when to sow parsnips, the answer is early in the year, from February onwards. So, how late can you sow parsnips? Well, at the very latest, by mid-May. Only sow early-ripening parsnip varieties in May to ensure that the parsnip growing season will still be long enough to get a good crop of roots. Always sow parsnips directly in the bed where they will grow. They do not respond well to being transplanted, as disturbing their roots causes distorted root growth in the parsnip seedlings.
Where is the best place to grow parsnips?
The best soil for parsnips is well-drained, deep and rich. Waterlogged and compacted sites are not very suitable for growing parsnips. Parsnips prefer a slightly acidic soil with a pH between 5.5 and 7. Parsnips like a sunny to semi-shady location. Before sowing parsnips, make sure to remove stones from the bed, as they can cause the roots to fork as the crop grows. Do not add manure to the growing site because adding manure will promote vegetative growth rather than root growth and also increase the risk of carrot fly (Psila rosae) infestation.
Avoid planting parsnips after crops such as carrots, parsley (Petroselinum crispum) or fennel (Foeniculum vulgare), as they suffer from similar pests and diseases. Growing the crops repeatedly in the same space can increase the risk of infestation. It is best to leave 4 to 5 years between growing umbelliferous plants (Apiaceae) in the same spot.
Tip: consider growing shorter varieties of parsnips on heavy soil rather than the ones with long elongated roots. Varieties with shorter wedge-shaped roots include ‘Albion F1’ and ‘Palace F1’.
Growing parsnips in raised beds
Parsnips are suitable for growing in raised beds, which are a good choice if your garden soil is not suitable for the crop. In fact, growing parsnips in raised beds can be beneficial, as you can control the quality of the soil conditions that the parsnip will grow in. Fill the raised bed with layers of different soils, using a rich soil that drains well as the top layer and a middle layer of compost, such as our Plantura Organic Enriched Compost, which will provide the parsnips with an ideal pH and plenty of nutrients, as well as support soil organisms. Sow the parsnip seeds directly into the raised bed. Depending on the depth of the raised bed, consider using shorter roots like you would on heavy soil, as recommended above.
- Perfect for all crops and ornamental plants with a high nutrient requirement & for raised beds
- Improves soil quality & promotes healthy root growth
- Peat-free & organic soil: CO2-saving composition
Growing parsnips in containers
Parsnips are not really suited for growing in containers, due to their long roots requiring a very deep container. If you wish to try, choose a container that is 40 to 60cm deep and fill with a rich soil, like our Plantura Organic All Purpose Compost. It is 100% natural and has all the nutrients needed for strong, healthy plants. Moreover, choose a shorter-rooted variety.
- Perfect for all your house, garden & balcony plants
- For strong & healthy plants as well as an active soil life
- Peat-free & organic soil: CO2-saving composition
How to grow parsnips from seed: step by step guide
Before sowing parsnip seeds, rake and level the bed, making sure to remove all stones and debris. When growing parsnips from seed, space rows 30cm apart with 1cm deep drills. Sow the parsnip seeds around 3cm apart along the drill. Thin the seedlings to a 15cm spacing as they grow. Water the drill carefully and keep it moist until germination, which can take up to 4 weeks. Parsnip seeds need a minimum of 8 °C for germination, but ideally, delay sowing parsnip seeds until the soil temperature is around 10 to 12 °C to improve the chances of successful germination. Trying to grow parsnip from seed too early, when the ground is wet and cold, will increase the chance of the seeds rotting in the ground. Water the seedlings in dry weather and keep the rows weed-free to reduce competition for the crop. Parsnips are drought-resistant crops once established and will only need watering if the leaves show signs of wilting.
There is a popular method of growing parsnips in toilet rolls. To do this, fill the cardboard inner rolls with compost and pat down to remove air pockets. Sow three parsnip seeds per roll 1cm deep and ultimately thin to leave just one remaining. Check the rolls daily for watering. As soon as the seedlings show their first true leaf, plant the entire roll out into the garden and the cardboard roll will decompose in the ground as the parsnip grows.
How to grow parsnips from tops
You can regrow your parsnip scraps to make new parsnip plants to grow in the garden. Growing parsnips from tops is simple. After harvesting your parsnips, cut off the top 1.5cm of root with the leaves attached and place the top in a glass of water. Within a few days, there should be signs of new roots and fresh green leaves on the top. After 2 to 3 weeks, the resprouted parsnip can be planted in a pot or out into the vegetable bed to grow on.
The best companion plants for parsnips
When companion planting with parsnips, good neighbours for the roots include onions (Allium cepa), garlic (Allium sativum) and leeks (Allium porrum), which help repel aphids (Aphidoidea) and flea beetles (Chrysomelidae). Some other good parsnip companion plants include lettuce (Lactuca sativa), Swiss chard (Beta vulgaris), beans (Phaseolus) and peas (Pisum sativum).
While it may seem that carrots and parsnips should be good companion plants, it is not the case. They are vulnerable to similar pests and diseases, so planting them together increases the risk. This is the case for carrot root fly and carrot blackhead (Alternaria). Other umbellifers that are not recommended as parsnip companion plants include parsley, fennel and celery (Apium graveolens).
Carrot root flies can wreak havoc on carrot and parsnip crops. Find out how to protect your crops from the pest in our expert article on protecting crops and preventing a carrot fly infestation.