Swede – Brassica napus var. napobrassica
Turnip – Brassica napa
Radish – Raphanus sativus
The English word swede comes from the vegetable’s origins in Sweden, around 500 years ago, probably in a field where brassica seed was being grown – swedes are a cross between cabbage and turnip.
It has a range of names, including ‘Swedish turnip’ and ‘neep’ in Scotland, and is called ‘turnip’ in parts of England. The Swedish word ‘rotobagge’ (meaning thick root) has been converted to ‘rutabaga’ in North America, where it may also be called the ‘Swedish turnip’ or ‘yellow turnip’.
This lesson also covers white turnip, partly for the context it gives to swede. White turnips contain more water than swede and are therefore less nutritious, although early-season turnips in springtime can be sweet and special.
Autumn turnips, in particular, have a pungent flavour. When we lived in France and shared a meal with neighbours, the old farmers would not eat turnip at all. It reminded them of starvation rations in wartime.
I have also found space for radish in this lesson. It was never going to make a whole lesson but fits nicely at the end here, in a separate section. It’s another close relation to turnip.
- Days from seed to first harvest: 40 for summer-sown turnip, 120 for summer-sown swede
Swede seeds sownSwedes ready to harvest(Cooler climates) Mid to late springFrom mid-autumn to early springEarly summerFrom mid-autumn to early spring
Turnip seeds sownTurnips ready to harvestLate winter to very early springMid to late springLate summerAutumn mainly
- Best climate is temperate and damp, not too hot and dry in summer, with a damp and mild autumn.
Why grow them
Swedes are the bass notes of winter. They won’t set your meals alight but they are always there when needed, often in quantity. Around here they are often on restaurant menus and more delicious than I can ever make them – it’s to do with the addition of butter!
For turnips, the ones I recommend are first sowings, for those early and sweet roots during the hungry gap. It’s good when they crop before pests arrive, especially cabbage root fly. Plus you can eat their leaves during the hungry gap and in late winter too, if roots have survived in the ground – they then grow new leaves before flowering.
Pattern of growth
Both of these are biennial, so they overwinter as a root then flower in the spring. Turnips can also flower in the summer after being sown very early because, if they experience enough cold while germinating and growing as seedlings, this triggers a ‘winter experience’ followed by ‘second season’ flowering.
The main period of harvest is winter. These are roots to store while in the dormant phase, which ends in early spring.
Suitable for containers/shade?
You can grow these vegetables in shade since they are brassicas, which like conditions to be moist and not too hot.
I am not convinced that they are worth growing in containers, with the one exception of early turnips, because they are rapid and do not grow large, therefore need less space. You could grow them before, say, transplanting tomatoes in the same container.
There is just one swede F1 variety, Tweed, though I did not notice enough difference from the open-pollinated varieties to recommend it.
I have found little difference between Joan, Helenor, Gowrie and Marian. All are good, and the latter claims resistance to clubroot.
There is more choice in turnips – Noir d’Hiver, for example, is a tasty winter turnip that stores well.
Fast-growing, open-pollinated varieties include Purple Top Milan, Manchester Market (yellow) and Atlantic Giant (white).
For sweet, white and perfectly round early turnips, it’s hard to beat the hybrids such as Tokyo Cross and Hakurei. You can pretty much think of them as a catch crop – sow them early and harvest them early, when they are not much larger than radish.
Sweetbell F1 has similar attributes, with purple colour on the shoulder.
Turnips are more viable for direct sowing than swedes because of their closer spacing.
- Seeds germinate in three to five days.
Swedes have just the one sowing time – around late spring, for winter harvests.
Turnips have two sowing times – very early, before spring if possible, or late summer.
Brassica seedlings are highly vulnerable to pests, especially to flea beetles in the spring; therefore it’s worth multisowing in modules under cover. Turnips grow well in clumps of three or four, while swede do best as singles.
See the video above for details of sowing swedes. The options are either to sow in a tray for pricking out seedlings or to sow two seeds in each module cell and then, after ten days, thin to one swede plant per cell.
Once seedlings are established, they grow better in the ground than in a pot. However, if your bed is not ready, pot them on so that growth continues.
We did this in 2020 and, from the potted plants, transplanted a few swedes all of five weeks later than the first planting, when they had all been sown at the same time. I was impressed that the later-planted swedes grew so fast and made a great harvest – this shows the options we have.
- Brassicas are tough plants and put up with interruptions to their growth.
Transplant size and time
Smaller or larger – all sizes are good for swedes, as long as they are in the ground before midsummer. At Homeacres, that translates to mid-July, and the last date for transplanting to have a decent size of harvest.
For early turnips, it’s best to transplant four-week-old seedlings, no older, so that growth is not checked at all. Late turnip transplants are best in the ground by early autumn.
Set plants deep, with as much of the stem buried as is feasible in your soil. Often this could be 5 cm/2 in of stem.
- For swede plantings, it’s best to cover with mesh against insects – see ‘Gall midge’ below.
- For early turnips, lay a fleece cover directly on top of transplants to speed their harvest, well before flowering initiates in late spring. The fleece also protects leaves from flea beetles and root flies.
Swedes grow large, at 35 cm/14 in. Vary spacing a little according to the size of harvest you like. The closest is 25 cm/10 in – any closer risks a higher proportion of leaf compared to root.
Multisown turnips of early plantings can be 25 cm/10 in between clumps, which is close because they don’t have time to grow large. Plantings of late summer grow well at 30 cm/12 in between clumps, or in rows 25 cm/10 in apart and 7 cm/3 in between each turnip.
Interplants between swede
I have discovered that the main options are transplants of salads for winter, in the gaps between swedes during mid-autumn. This links to removing the older leaves, which serves to open space between each swede root.
Salad plants that I do not use are brassicas, such as mustard, because they are in the same family. This means a slight increase in the amount of flea beetle damage to salad leaves and root fly damage to roots.
- A really good interplant is corn salad, because it grows slowly and does not mind being initially overshadowed by swede leaves. Best spread a little compost first, between and right up to the swedes.
- As swede growth slows in late autumn, the corn salad grows larger. It never makes a large plant and may crop until mid-spring – see Lesson 25.
You can also direct sow corn salad, by the end of September or not too far into autumn. Drawing a drill will damage a few swede roots, not a major issue, or you can simply drop a few seeds on the surface, then spread compost on top of them and around the swedes. This is to feed and protect soil life over winter.
All brassica plants thrive in moist soil, yet they also tolerate dry conditions. Of these two plants, turnips grow faster and have the most increase in growth from being watered in any dry weather, particularly early plantings in a dry spring.
If your climate has a dry summer, as I hear it does in Oregon, for example, then swedes will benefit from a good dose of water, say, once a week. They may not grow a great deal in the dry conditions but a baseline of just-sufficient water keeps them in good health.
- Then, when it rains in the autumn, they put on a lot of weight.
Extra mulch to retain moisture?
The edible part of both plants is appreciated by slugs, so compost is the best mulch because it harbours fewer mollusc pests. I do not recommend using straw or plastic.
- Leaves grow fast after transplanting and soon shade the ground.
How to judge readiness
Roots are ready to harvest whenever they look large enough to eat. Only early turnips have a time limit on harvest because their harvest time is so close to the time of flowering.
- With summer plantings, the flavour improves through autumn with falling temperatures, and swedes, in particular, can become noticeably sweeter during the depths of winter.
- As spring approaches, the texture becomes tougher as fibres develop, which are part of a flower stem initiating.
How to pick
Swede roots are tenacious, so it helps to use a sharp trowel or knife to cut under the swede, leaving many small roots in the soil to feed organisms there. Turnips twist out easily, and rotating the root should give a clean break with the soil, leaving most roots in the ground.
Twist or cut off all leaves and rinse the roots in clean water immediately after harvest, before soil dries on them and sticks.
From autumn harvests, turnips stay in a nice condition for no more than two months, while swedes can store for the whole winter. Keep them anywhere cool and damp, preferably below 10 °C/50 °F.
Roots stay in the best condition when you leave some soil on at harvest, for long-term storage.
Neither of these vegetables is straightforward – they make large plants when flowering and you need several for cross-pollination. If you have the time and space to do this, seedpods will develop by midsummer; it’s then a long job to pick them and extract the seeds. Have a look at Real Seed’s advice.
During spring, the majority of damage is caused by flea beetles hopping onto leaves and eating little holes. They cause most damage to small and tender leaves, which significantly compromises new growth. The beetles are dark and the size of a pinhead, sometimes gathering in clouds.
- Cover spring plantings with either fleece or a fine mesh, as soon as transplants are in the ground. There will still be some damage, but less.
Caterpillars eat the leaves but often not too severely, and there is time for new leaves to grow in autumn and for a harvest still to happen. Keep a mesh cover over summer plantings for six to eight weeks, so they establish strongly before any pest damage.
- You can leave a mesh cover on until harvest. If you remove it, watch for caterpillar damage and either squash them or spray with Bacillus thuringiensis.
Perhaps the most damaging of the many brassica pests is the gall or swede midge. This insect eats the tender heart leaves of any brassica during early to midsummer, resulting in a halt to new growth for up to a month.
- Damage from the midge may prevent swedes from making a decent harvest – growth becomes multi-stemmed and weaker.
- Best remedy is a mesh cover, from the day of transplanting until sometime in late summer. Here we remove covers by mid-August.
Clubroot or Finger and Toe (Plasmodiophora brassicae)
This shows as yellowing/chlorosis of leaves and stunted growth, with swellings on roots and lower stems. Infected plants rarely make a worthwhile harvest when soil is regularly dug or tilled. However, with no dig, the increase of soil health, including mycorrhizal associations with plant roots, gives more chance of worthwhile harvests.
The spores are spread by any import of infected plants or soil, by cultivations that move and disturb soil and by use of infected tools. Spores remain dormant for several years until they meet host plants again.
- There are some resistant swede varieties, such as Marian; however this is resistance, not immunity, and growth is still reduced.
- Clubroot lives best in slightly acid and wet soils. Spread a little lime before planting, and no dig improves drainage plus reduces the spreading of spores.
Clearing is rapid because your harvest results in empty ground, once you remove any lingering weeds. After autumn harvests, rake level and then spread 2.5 cm/1 in of compost. Your bed is then ready for spring planting.
Harvests of early turnips finish in time for new plantings of any summer vegetable, from leeks and salad onions to carrots and beetroot.
After autumn harvests, you have the possibility of growing any vegetables the following spring, except for brassicas. In terms of rotation, I find best results from leaving at least a few months between plantings of the same family.
From its origins, possibly in Southeast Asia, radishes now grow worldwide in many forms. They have been bred into long white daikon in Japan, red globe radish in Europe and radish for salad leaves in the UK. There are also winter radish grown as a fodder crop for farm animals.
Radish are in the Brassicaceae family, worth remembering for the shared pest issues.
- Days from seed to first harvest: 35–40
The best climate is temperate and moist, not too hot, and definitely not arid.
Why grow them
It's a personal call, as not everybody likes radish. My dictaphone calls them rubbish! Actually I love them in very early spring, when the cool conditions mean they are juicy and not too pungent. Their harvest is the first root vegetable of every year.
You can eat radish leaves, and their speed of growth on first sowings of red globe radish makes them a welcome early green. The reason they are not commonly eaten is the spiky leaf-hairs, which are not comfortable on the tongue.
- There are varieties of ‘leaf radish’, which have been bred to grow smooth leaves with a fine radish flavour, without spiky hairs.
Furthermore, there is an incredible range of radish for sowing in late summer, to harvest through the cooler months. They have amazing colours and a decent flavour, plus you can cook them a little. All radish, even globe types which are normally eaten raw, are tasty when lightly fried or sauteed, even roasted. Treat them like turnips, their close relations.
Pattern of growth
Radish are biennials grown as annuals. They flower in spring, but a rapid rate of growth means that you have time to grow a harvest in early spring before they flower. Therefore the harvest of early spring needs taking quickly, before the radish grow woody as they start to make a flower stem.
Autumn harvests just keep growing, and radish resist a certain amount of frost. In cold climates they can be stored as you would a carrot or beetroot – unwashed and in boxes, cool and moist.
Suitable for containers/shade?
They are ideal for containers, thanks to a high speed of growth and not needing a large root run. In 2013, I set up a comparison of three composts in the same sized boxes and noticed little difference. One was old cow manure, and the radish grew as well in this as those in two different batches of homemade compost. One of the composts was from a heap that I had found here in December 2012.
Radish also grow well in shade; in fact, they like more temperate conditions, so shade is good if your climate is hot and dry. Best containers for radish are wide and flat, to give maximum surface area for many leaves to grow, resulting in worthwhile harvests.
There are so many! One troubling thing though, which I have noticed recently, is the lack of maintenance given to traditional varieties such as French Breakfast. Also, in 2020 I grew some F1 hybrid radish that were disappointing, compared to traditional carefully selected radish from Bingenheimer Saatgut in Germany.
French Breakfast is a pretty, long radish with a distinctive white tip; it needs eating young and small, often goes hollow when larger and has a mild taste.
Rudi is a firm and dark red, round radish; it stands well without going soft.
Black Spanish is a large winter radish, with white flesh under a dark skin.
Mooli Minnowase grows a long, white mooli radish – a good variety if well maintained, also called Daikon.
Shawo Fruit is a bright green 'fruit' radish, semi-long and cylindrical – sow just after midsummer.
Green Luobo has green streaks inside a white exterior, is firm and crisp and good for pickling – sow as for Shawo.
Candela di Fuoco can be sown early or late, grows long and red, as in the photo below, and stays reasonably firm.
Sow and propagate
Even though it is a root vegetable, radish transplants really well. As with beetroot and turnips, the root part that we eat is actually a stem swelling just above root level.
- Seeds germinate in two to four days, perhaps the fastest vegetable.
For red globe radish, sow under cover in late winter to early spring – early spring is good for direct sowing outside. The summer sowing is in early autumn, either under cover or outside direct.
For larger, winter radish, sow mid to late summer.
Using module trays, sow five seeds per cell, and thin to four seedlings if need be. Four in a clump gives a lovely sized radish, and plenty of them!
For sowing outside, draw a drill about 5 cm/2 in deep from the top to the bottom of the drill, and make the drills as close as you can, as little as 15 cm/6 in apart. Seed at a spacing of approximately 1 cm, or three per inch.
You can also sow radish in the same drills as your carrots and parsnips.
Transplant size and time
Seedlings grow rapidly under cover, but for first sowings it's still early in the year and quite cold, so they are often about four weeks old when you transplant them. Later, when it’s less cold, they can be as little as two weeks old, and it works really well to transplant smaller rather than larger seedlings.
Radish seedlings make long stems, therefore your planting holes want to be on the deep side. Push in the module cells firmly so that all stems will have soil or compost around them.
You don't need to fill the holes after transplanting because watering will do that for you. It's good to water in straight after planting.
- Early plantings benefit from a fleece or row cover, both for weather protection and against flea beetles, birds and rabbits.
- You can keep a cover on until harvest time, resting on the leaves – they easily push it up.
For red globe radish, very little space is needed, just 15 cm/6 in between multisown clumps. Your direct-sown seedlings may need thinning to 1 cm/two or three radish per inch.
Winter radish need 5–10 cm/2–4 in of space, in 20 cm/8 in rows, or 30 cm/12 in between clumps.
Radish are watery, so keep soil moist most of the time. Nonetheless, it is still possible to give too much water, as with any plant. Remember that excess water means a reduction in soil air. In dry weather, a good dose of water twice a week should be sufficient.
Harvest times and methods
How to judge readiness
You can pull red globe radish as soon as they are visible and identifiable. The first small radish are sweeter and milder than later ones, so it's good to begin early.
You will probably have a fair amount to eat from one sowing, and starting to harvest early gives more time to eat it all. As it warms up in spring, you suddenly have an abundance, and mature radish develop a pungent flavour, especially in hot weather.
- Once you see any flower stem, best harvest all radish because they are now becoming tough in texture.
- Winter radish stand for a long time without losing quality. Harvest once they look close to the size you want – they can remain in the soil for a long time.
How to pick
With multisown clumps, you can twist out individual radish and leave the rest to grow some more. Or, if you have a lot coming ready, simply twist out whole clumps.
For intersown radish between carrot and parsnip, easing them up carefully does not disturb the surrounding seedlings, as shown in the photos above. The carrots and parsnips look a little straggly for a while, then grow strongly.
When to pick and how often
Red globe radish lose moisture rapidly after harvest, so you may be harvesting every day or two, for the juiciest roots.
Winter radish are more solid in texture and keep well after picking, like turnips, so you can harvest them ahead of eating.
Root vegetables lose moisture through the leaves immediately after harvest, so twist off leaves as soon as you have picked the radish, give them a rinse in cold water and they are good to eat for two or three days, just kept in a bowl.
For winter radish, keep them cool – they can stand a little freezing. In a box in the shed, they can store for two to three months.
As long as there are no other flowering brassicas nearby, this is not too difficult. Flowering is in early summer. Seed pods are also edible when green, sometimes called 'rats’ tails'.
Have six or up to ten of the best quality radish, growing quite close to each other; put a stake in the ground nearby and tie their flowering stems to the stick. Once seed pods are mostly dry, pull all plants and hang them upside down in a ventilated place, under cover. Later you can rub out the seeds at your leisure.
Spring radish leaves are manna from heaven for flea beetles, which feast on small and tender leaves. Hence my recommendation to cover, using fleece on early plantings to also increase warmth. Then use mesh covers on later plantings.
Another common pest is cabbage root fly, especially by late spring – it can ruin whole sowings. The little maggots tunnel into radish roots and quickly cause enough rotting to spoil your chances of a decent meal. Once again, covers are the answer, and sowing early helps so that harvests happen before the flies are too common. More flies hatch in early autumn, when mesh covers may also be needed.
Slugs chomp into radish roots. As usual, I recommend having minimum slug habitat nearby, no old and rotting wood for example. Plus no dig reduces slug population through better soil structure and the presence of more slug predators.
After a final harvest of spring-sown radish, there are often a few tiny or misshapen radish to remove, together with a few weeds. Then rake lightly to level the ground and you are ready to transplant or sow again.
After winter harvests, spread compost as soon as the ground is clear.
This depends on the date of final harvest, and you can transplant any vegetable which is in its right season – see my sowing timeline. I do not worry about rotation before or after radish, because they are in the ground for such a short time.
Even winter radish, which may be in the soil for three to four months at the end of a season, can be followed by brassicas in the spring if that is what you want to grow there.