Swedes and turnips are cold tolerant crops related to cabbages, kales and sprouts. As they grow, the lower parts of the plants gradually swell up to produce bulbous organs made up of a firm-textured flesh that is either white or yellow in colour. The taste of the flesh is a pleasant mix of bitterness and sweetness, elevating both vegetables to gourmet status whether they are mashed, stewed or added raw to salads.
Superficially, swedes and turnips seem indistinguishable from each other. Nothing, of course, could be further from the truth, and a closer examination of the two reveals striking differences between them. These differences extend to how they are treated in the garden, and while swedes are quite straight forward to grow, turnips tend to be more nuanced and convoluted.
Swedes are the quintessential winter vegetable best sown from late May to the first half of June. If the timing isn’t right, there are stiff penalties to pay: sow too early, and the plants may bolt or develop powdery mildew; delaying sowing until late June and July will mean yields may be checked by late season cold weather.
Swedes can be started by direct seeding into a seed bed, or by sowing into modules to produce young transplants. For direct seeding sow the seed outdoors into in a well-worked, well-fertilised soil that is high in organic matter. Sow seeds 1cm deep in rows about 40cm apart, leaving 4 to 5cm between seeds. After germination, gradually thin the seedlings to leave 15 to 20cm between each one. Alternatively, grow in ‘stations’ spaced 25×25 to 30x30cm apart, sowing three seeds at each station and pulling out any extra seedlings to leave just one.
Swedes can also be started as transplants by sowing seeds in module trays divided into small cells. Put two to three seeds in each cell, thinning early to leave one seedling. Keep the trays outdoors, and transplant when the seedlings have two to three true leaves.
Once the crop is growing, all you have to do is weed, water and watch out for pests (see below). Harvesting can begin some time in late September, but it is better to wait – the flesh gets sweeter after the plants are exposed to cold temperatures. Because the crop is so cold tolerant, it can be left standing in the garden and harvested through the winter, though it will come to a natural end by March.
Numerous varieties are available, mostly with yellow flesh and purple tops. Two worthy candidates for the garden are Marian and Ruby, both of which are resistant to powdery mildew.
All things considered, turnips are an undemanding and flexible vegetable offering distinct choices of where and when they can be grown. The flesh can become quite tough if left to get over-mature, so it is better to sow little and often, harvesting the roots when they are between 4 to 7cm in diameter.
For an outdoor maincrop
Turnips can be sown any time between March to July. Some good varieties to try are Purple Top Milan, a popular white-fleshed variety with a flat shape and purple top, Golden Ball and Tokyo Cross. Though slow growing, Golden Ball has an appealing yellow flesh that is firm-textured and distinctively flavoured. If you want speed, though, Tokyo Cross is a good choice as it can sometimes be harvested in less than 40 days. Unfortunately, early sown crops of Tokyo Cross are prone to bolting, so delay sowing until May. Because it is so fast, it might be worth sowing as late as the first half of August – roots should be ready to harvest before cold weather sets in.
Other sowing times include:
Late crops outdoors
For a late season treat, sow the variety Golden Ball from mid-July to mid-August. It is fairly hardy and will stand at least to December – or even longer if the weather holds up. Start harvesting when the roots are about 7 to 8cm in diameter.
Greenhouse or tunnel crops in the autumn
Sow undercover from the middle of August to the beginning of September. Tokyo Cross and Sweetbell are white-fleshed, quick-growing varieties that will be ready to harvest well before Christmas.
Greenhouse or tunnel crops in the spring
Sow undercover in February. Milan White is a competent white-fleshed variety that suits this time slot, but be careful: the crop may still be in the ground when it’s time to transplant your tomatoes and peppers in the spring.
To start a turnip crop, seed can be sown directly into a seed bed or sown into modules and started as transplants. For direct seeding sow the seed 1cm deep directly into well-prepared ground of good tilth and fertility. For late cropping varieties such as Golden Ball, leave 30cm between rows and 15 to 20cm between plants in a row. Plants of the other varieties can be grown 10 to 12cm apart in rows separated by 20 to 25cm.
Late cropping turnips can be started as transplants using the same method recommended for swedes. For the other varieties, you can adopt a multi-seeding technique by sowing four or five seeds in each cell of a compost-filled module tray. The goal is to grow three seedlings per cell, pulling out any redundant extras after germination is complete. Once the roots fill the cell, take the seedlings with their ball of compost from the tray and transplant them as a bunch in the garden, spacing the bunches 25 to 30cm apart each way.
Pests and diseases
The pests and diseases of both swedes and turnips are almost too numerous to mention. Suffice it to say that rotations, appropriate sowing dates, choice of varieties, and the use of fine-meshed netting draped over the plants will control the most important ones.
The difference between Swedes and Turnips
Swedes and turnips, like chalk and cheese, are so different from each other that they can’t be confused. When compared on different levels, it’s easy to see why:
They belong to different species: swedes are classified as Brassica napus, turnips as Brassica rapa.
Swedes are hardier and more cold tolerant than turnips.
Swedes have denser flesh than turnips, which is why they are harder and more difficult to peel and chop.
Both vegetables produce swollen parts that are eaten. In turnips, the swellings are formed from the top part of the roots. In contrast, with swedes the swollen ‘root’ includes both the upper part of the roots and the lower part of the stem, giving ‘roots’ a neck. The necks vary in length and are marked with scars left by detached leaves.
Turnips are smaller than swedes and are harvested in a shorter time.
What is bolting?
‘Bolting’ refers to the production of flower stems in both leafy and root vegetables. With turnips and swedes the first sign of bolting is the elongation of the stems. From the plant’s point of view bolting is a good thing, it is the start of its reproductive stage that ends in the production of seeds. From a gardening point of view, though, it is undesirable as it brings to an end the productive life of these crops.
Though inevitable, bolting can be delayed by changing sowing dates as cold conditions are a trigger for bolting. The period of time a plant stays in the vegetative stage varies between varieties, so it also worth growing bolt resistant varieties.
Swedes and Turnips – still the poor relatives
Sadly, swedes and turnips do not immediately conjure up visions of gastronomic pleasure, and all too often, they are the go-to vegetables when nothing else is available. Granted, they are not as glamorous as tomatoes and cucumbers, or as attractive as peppers and aubergines. But they are easy to grow, delicious to eat, and available for a large part of the year. With so much going for them, surely they should be put at the front of the queue and given the status they deserve.
© Michael Michaud