How to Grow Rutabaga (Brassica napus)

By Matt Gibson and Erin Marissa Russell

One of the most perfect vegetables to grow in the fall garden, rutabagas are a natural cross between the cabbage and the turnip. Rutabagas were one of the first crops that were used as Jack-o-lanterns, often carved for decorative purposes just like pumpkins. They ripen during cool autumn weather and their best flavor only develops after a little bit of exposure to frost.

Known by a long list of names, most of which refer to them as some kind of turnip, the Rutabaga is also known as Russian turnip, Swedish turnip, Swedes, winter turnip, yellow turnip, and Canadian turnip. The turnip names are given to the rutabaga for good reason, as the two plants are very similar, both in overall appearance, and in growing environment and care needs. They are both great additions to soups and stews and they both can be cooked or mashed and paired with meats for In fact, some people use the terms rutabaga and turnip interchangeably, thinking that turnip and rutabaga are the same plant.

Despite their similarities, rutabagas and turnips are two different plants. Turnips produce a more potent flavored vegetable with white flesh, and rutabagas produce round, firm roots with sweet, yellow flesh. Though they are both members of the cabbage family, the two vegetables have some distinct differences.

Rutabagas are typically yellowish or brownish and are usually much larger than turnips. Turnips are generally white and purple and are harvested at a much smaller size than the rutabaga. Turnips can be grown in a variety of climates with success, but rutabagas are a cold weather crop that will not grow in warm climates.

Varieties of Rutabaga

There are about a dozen different types of rutabagas available to modern gardeners. Here, we have gathered together a little bit of information on some of the most popular cultivars to help you decide what varieties to grow in your garden.

Most Popular Varieties of Rutabaga:

Laurentian – This Canadian heirloom rutabaga cultivar is one of the more popular varieties for several reasons. It is attractive, easy to grow, mild flavored, and one of the smaller rutabaga options perfect for container gardening or for small garden spaces. The Laurentian rutabaga produces small to medium-size roots ranging from four to six inches in diameter. The eye-catching roots are cream-colored with red tops. This variety matures in 100 days, stores well in cool storage areas, and self-seeds in the garden.

American Purple Top – Often confused with Purple Top Turnips, this rutabaga cultivar can be identified by its yellow or cream-colored bottom, as opposed to the white-bottomed turnip variety. The flesh of the American Purple Top turns a deep-orange when cooked and is a great choice for winter storage. Maturing in 90 days, this cultivar produces large, uniform roots and self seeds in the garden.

Joan – Well suited for fall harvesting, this disease-resistant, purple-topped cultivar produces round roots in 120 days. When harvested early, roots are mild and sweet, but should be left in the ground through the first frost to improve the flavor.

Nadmorska – This Lithuanian cultivar is more elongated than the more common varieties (Laurentian and American Purple Top). These early maturing rutabagas are large, round but slightly elongated, quick to mature and prolific producers. The Nadmorska rutabaga produces large, green-topped tubers with golden flesh and a slightly more mustard forward flavor than purple top varieties.

Marian – A great selection for late summer and early fall harvesting, the Marian cultivar matures in 85 to 95 days, producing large, yellow tubers with purple tops. The Marian rutabagas grow up to eight inches in diameter and store well in cool storage areas like root cellars.

Other Heirloom and Gourmet Rutabaga Varieties:

Champion A Collet Rouge – Excellent fried or roasted, this cultivar boasts a subtle sweet flavor from yellow roots with purplish-red tops. Popular with gourmet chefs.

Collet Vert – Yellow roots with green tops, favored by gourmet chefs for its rich flavor and colorful appearance.

Wilhelmsburger – An elongated (not round) German heirloom variety with a strong flavor, green skin, and yellow or golden flesh.

Gilfeather – This American heirloom is coveted for it’s sweet flesh and delicious green tops. It has golden root-bottoms with green tops.

Other Noteworthy Rutabaga Cultivars:

Helenor – Known for high yields

*Macombers – Several cultivars with white bottoms and bright green tops.

Long Island Improved – Has a small taproot but large bulb

Sweet Russian – Very frost tolerant, due to its habitat.

Pike – Also quite frost tolerant, this variety can be left in the field for multiple light frosts which will greatly improve its mildly sweet flavor.

*There are several different Macomber cultivars, and there is some debate over whether they are turnips or rutabagas. Their white flesh points to turnips, but their sweet taste points to rutabagas. Grow them and decide for yourself.

Growing Conditions for Rutabaga

Rutabagas are biennials commonly grown as annuals in the US, and will often go to seed in the first year if they are planted in the spring. Rutabagas enjoy full sunlight but can tolerate partial shade. They prefer a nutrient-rich, well-draining soil with a slightly acidic pH in the range of 6.0 to 6.5. Good soil fertility is required to help them thrive during a long growing season. Well-draining soil is essential to avoid bulb rot issues.

How to Plant Rutabaga

Plant rutabagas in early summer or midsummer, allowing ten to 12 weeks of growing time before the first fall frost in your area. Start seedlings indoors during especially hot summers, setting them outside when it’s cloudy. In cool climate areas, direct seed in the ground and thin to every eight inches once seedlings have germinated.

Pick a location with full sun and prepare the soil before planting by digging in a good amount of organic fertilizer or well rotted manure. Too much nitrogen can stunt bulb formation, so only use half of the product’s suggested amount when preparing your beds, waiting to apply the other half until several weeks later, after the plants have been thinned and the beds have been treated for weeds.

Keep an eye out for boron deficient soils, as rutabagas are very sensitive to boron deficiency. If you think your soil might be lacking in boron, sprinkle some borax into the planting row or mix some borax with water during a single watering while your plants are still young. Either way, be careful not to add too much borax, as it is highly concentrated, and each plant only needs a few pinches.

Plant seeds 2 inches apart and one-half inch deep in rows spaced 14 to 18 inches apart. Allow four to seven days for germination. After germination, thin to eight inches or more between each plant. Overcrowding your rutabaga plants will cause excessive top growth and stunted roots. Rutabagas are a cool season crop and they will not stand high temperatures for extended periods. Sustained temperatures over 80 degrees F will cause plants to bolt prematurely.

Care for Rutabaga

Provide at least one inch of water per week to ensure proper root development. More water may be needed during particularly hot or dry weather periods. If rutabagas are exposed to extended dry soils, they will crack and won’t become sweet as they mature. If you amend your soil before planting and start the season off with lots of organic matter in your beds, you won’t need to add any fertilizer during the season. Side dressing with well-rotted compost around mid-season will give them a nice boost that will get them through to harvest time.

How to Propagate Rutabaga

Rutabagas are propagated by seed, and if planted in the spring, most varieties will readily self-seed if left in the ground.

Garden Pests and Diseases of Rutabaga

Caring for your rutabaga crop well and ensuring they get the sun and soil type they need will go a long way toward preventing issues with pests and disease. However, even the most careful gardener is bound to experience an infestation or plant disease now and again in his or her garden. Rutabagas often deal with many of the pests and diseases that cabbages and other brassica crops struggle against. Here are the most common problems people experience when growing rutabagas, along with tips on what you can do to resolve them.

Alternaria blight: Alternaria is a seedborn fungal disease. In its early stages, when it impacts seedlings and young plants, the effects can resemble those of damping off. Frequently, however, this slowly moving disease doesn’t begin to show itself until plants are older. It’s often detected in the flowering and fruiting stage, at which point it will have had plenty of time to spread. Gardeners tend to notice spots on foliage that can be as large as a thumbprint in yellow or brown that spread out in widening rings. Affected plants should be removed and destroyed, and they should not be used in compost or fed to people and animals. You can learn more about alternaria in our article Dealing with Alternaria Blight.

Anthracnose: Anthracnose is a fungal disease that can affect almost every part of a plant with gray or pink spots that resemble boils. It’s often spread by wind or water, so it tends to thrive in windy or wet conditions. Plants that contract anthracnose in the early stages of growth may die from the disease. You can prevent anthracnose by choosing seeds free of disease and cleaning garden debris regularly. Affected plants must be removed from the field and destroyed as soon as symptoms are evident. The quicker you catch anthracnose and remove the impacted plants, the less of a chance the disease will have to spread and affect more of your crop. That’s why it’s important for gardeners to vigilantly and frequently examine their plants for signs of anthracnose and other diseases. You can learn more in our Guide to Anthracnose Fungal Disease.

Aphids: Rutabagas particularly tend to have trouble with turnip aphids. Aphids as a whole come in lots of different shapes and various sizes, but all aphids are tiny and tend to congregate on the underside of foliage. They suck the moisture out of leaves, so if your crop is dealing with aphids, you’ll see leaves that are shriveled, misshapen, or distorted. You can treat aphids with a homemade mixture of one liter of warm water, four or five drops of dish soap, and a tablespoon of neem oil. Put the solution into a spray bottle, and treat plants with it every week or so until the infestation has cleared up. You can also spray aphids off the foliage with water using the pressure nozzle of your garden hose. You can learn more about aphids in our article All About Aphids, and How to Kill Them.

Caterpillars: Caterpillars are cute in their own way, but they can be responsible for major destruction in the garden. Examine your plants each day for caterpillars and their eggs, which you’ll find on the underside of leaves, either individually or grouped in clusters. Crush any caterpillars you find, or drop them into a bucket of soapy water as you work. Eggs should also be crushed, or for maximum caution, pluck the leaves where eggs have been laid off the plant entirely. Physical barriers like floating row covers can help prevent issues with caterpillars, as long as you put them up before any eggs are laid. Sprinkling some diatomaceous earth around plants you wish to defend can also keep caterpillars at bay, as it irritates their flesh. You can go on the defensive by growing carrots and parsley, then allowing them to flower so they’ll attract certain species of wasps that prey on caterpillars. (Serendipitously, these are not the wasps that sting humans.) The homemade neem oil treatment we described in the section on aphids above can also be used to deter caterpillars.

Clubroot: The most obvious signs of clubroot are underground, where roots will swell into misshapen, thick clubs. Clubroot is usually introduced to a garden on the wind or through infected transplants, soil, or compost. Examine transplants carefully for the symptoms in their roots before planting them in your garden, and ensure that your soil or compost is heated to kill pathogens before you put it to use. Clubroot can also be spread via gardening tools, so be sure to clean and sterilize your equipment as you move about the garden or after handling infected plants. Above ground, affected plants will show stunted growth, yellowed foliage, or a tendency to wilt. Immature plants may die early, while older specimens may grow to maturity without producing a harvestable rutabaga. Invasive weeds can be carriers without showing symptoms, so it’s important to weed your rutabaga plot carefully to prevent clubroot. If you suspect clubroot, turn up some sample plants to check for the swelling in the root systems. Any plants that are affected should be pulled up and either composted or buried, and then cole crops should not be grown in the area for five to seven years.

Downy mildew: Downy mildew is another fungal disease that is most prevalent in cool, wet weather. Rutabagas that are fighting downy mildew can look a lot like malnourished plants, with discolored foliage in shades of yellow or exhibiting a mottled pattern. The hallmark of downy mildew, however, are the fluffy fungal spores you can see on the undersides of foliage in shades of purple, gray, or brown. Plants impacted by downy mildew will succumb easily to other diseases and may also show stunted growth or drop their flowers and fruit. Although fungicide can be effective against downy mildew if it’s deployed early enough, the best way to fight downy mildew is to prevent plants contracting it in the first place. Control moisture in the garden by ensuring efficient soil drainage and watering plants at the base, not letting water splash onto their foliage. A layer of mulch can also help make sure water doesn’t accumulate or splash onto plants. Your rutabagas should also be spaced far enough apart to allow air to circulate between them. Learn more in our article Identify, Prevent, and Treat Garden Problems: Downy Mildew Fungal Disease.

Flea beetles: Flea beetles differ in appearance from the rest of their beetle brethren in their tiny size (just a sixteenth of an inch) and because they have enlarged back legs, which they use to jump like fleas. Many different types of flea beetles exist, some of which strike a range of plants, while others hone in on just one variety, but brassica crops are an especially common target. The tiny beetles can be hard to spot, so look for circular holes, especially frequent in areas of new growth, that give foliage a lace-like appearance. Because flea beetles spend their winters in brushy material, you’ll want to make sure no such material is anywhere near your garden plot. You can treat plants to deter flea beetles with a homemade spray made of 5 cups of water, 2 cups of rubbing alcohol, and a tablespoon of dish soap. Before treating all your rutabagas, do a spot test of the spray on a small area, and watch it for a day or two to ensure it won’t damage your plants. Floating row covers can also be used to keep flea beetles at bay. These insects are especially fond of nasturtium flowers and radish plants, which can be used as sacrificial trap plants to distract the beetles from your food crops. Planting basil and catnip has the opposite effect and will repel them from an area. You can also use a variety of methods to entice beneficial insects to visit your garden, as these insects prey on flea beetles. Learn more about how to encourage beneficial insects to visit your plants in our article Beneficial Insects for Gardens and Yards: How to Spot and Attract Them.

Root knot nematodes: These tiny worms live underground and feed on the root systems of plants, causing destructive knots or galls in the roots. In addition to plaguing crops, they also proliferate in invasive weeds, which can make them difficult to control. Above ground, plants suffering from root knot nematode infestation can show signs such as stunted growth, yellowed foliage, wilting in the hottest part of the day and recovering in the cool of the evening, producing few fruits that are small, and generally seeming unhealthy. You can pull some plants up to check for the telltale knots in the roots if you suspect root knot nematodes. To prevent this infestation, choose resistant varieties when possible, and avoid planting susceptible crops in places that have struggled with these nematodes in the past. Cleaning up garden debris and weeding carefully can also help prevent problems with root knot nematodes.

White rust: White rust is not actually a rust disease and instead is a fungal disease spread by relatives of the species behind damping off disease. Affected plants develop yellow spots that turn into pustules resembling white rust on the undersides of their leaves. If you see white rust in your garden, control its spread by removing and destroying any affected plants. You can prevent white rust by selecting resistant varieties to grow and by practicing good garden sanitation so no infected debris is left behind.

White leaf spot: White spot is a fungal disease that tends to affect cole crops, and as its name suggests, it’s evident by the pale spots scattered across foliage. As time goes on, the white spots can darken and eventually fall out, leaving small holes in affected leaves. It’s most prevalent in chilly, wet weather and tends to spread via the movement of wind or water (especially when it splashes onto foliage) or when infected plant debris is left in the garden. If your plants contract white spot, practice crop rotation and do not plant susceptible crops in that location for at least three years. You can treat white leaf spot with liquid copper, but preventive measures should also be deployed. Make sure to clean the garden of plant debris, especially debris from infected plants, being especially careful to clean the garden before winter sets in. Weeding your field meticulously and ensuring proper soil drainage are other ways to work against white leaf spot.

How to Harvest Rutabaga

Rutabaga greens can be harvested anytime after they reach four inches tall. If you take care not to harm the bulb during harvesting, greens will continue to grow for multiple harvests. Garden grown rutabagas tend to be more top-heavy than round, as the roots start to push up as they gain size. You can start harvesting rutabaga bulbs when they get to two or three inches in diameter, but keep in mind that larger bulbs will have better flavor, but can grow a bit tough. Early harvested roots at two to three inches in diameter will be very tender, but mild in flavor.

Rutabagas are also sweetened by a little bit of frost. For optimal taste, wait until bulbs are four to five inches in diameter, and have been exposed to one or two light frosts. You can dig them up in the fall, or in late winter in warmer areas, or leave them in the ground to experience a few frosts.

If you choose to leave them in the ground, protect them with a thick layer of straw mulch. As long as they are protected with a thick mulch layer and there is no hard freeze on the horizon, they will be fine left in the ground and harvested as needed.

Rutabaga foliage is edible, but most people prefer young leaves or the nutrient and antioxidant-rich sprouts instead. Before storing rutabagas, the foliage should be cut to within one inch of the crown with a sharp, clean knife.

How to Store Rutabaga

Once your rutabagas have been harvested, do ot wash them until you are ready to use them. You can store your rutabaga crop in plastic bags, either in the refrigerator or in a cold cellar, for months at a time. Make sure to store them well away from raw meat products that may drip juices onto the vegetables and contaminate them. When you are ready to prepare your rutabagas, scrub them well with a vegetable brush and cool or warm water (not hot water), and use a vegetable peeler to remove the outer peel.

If you have more rutabagas than you can eat before they will spoil, there are several ways you can preserve them. Canning is usually a good way to store homegrown vegetables, but rutabaga should not be canned, as their color and taste will change, making the flavor extremely strong. Instead, freeze any rutabaga you need to store long term.

To freeze your homegrown rutabaga, peel them and cut them into cubes, then blanch them in boiling water for three minutes. (To blanch, simply bring a pot of water to boil, then drop the rutabaga cubes in for exactly three minutes. Remove them with a slotted spoon, and transfer them to an ice water bath to stop the cooking process.)

Once the rutabagas have cooled, move them to a colander or rack where they can drain. Then load them into either freezer safe plastic zipper bags or freezer safe plastic storage containers, and put them into the freezer, labeled with the contents and the date. They will be good to eat for six months to a year after freezing them this way.

Considered a mix between a turnip and a cabbage, rutabagas were originally cultivated to feed livestock until humans recognized their nutritional value and appealing flavor. High in nutrients, dietary fiber, and antioxidants, and low in calories, rutabagas quickly found a role in the culinary world. Rutabagas, like other root vegetables, are high in anticarcinogenic compounds.

They are also a good source of vitamin C and several B vitamins, as well as several essential mineral compounds. Their nutritional value and low caloric content have earned them a place at the table as well as a spot in the garden.