How to Grow Rutabaga

A Cool Season Root Vegetable That Is Similar to Its Turnip Relative

Rutabaga growing in the ground

David Marsden / Getty Images

Rutabaga (Brassica napobrassica), is a root vegetable that's believed to have originated as a cross between the cabbage and the turnip. Also known as the Swede, they might not be as popular as their smaller and faster-growing turnip cousin, but they're still easy to grow and full of flavor.

Rutabagas have beautiful pale gold oval bulbs with a purple crown and a peppery, cabbage-like flavor. They're sweeter and more buttery than turnips, and the greens are also delicious.

The bulbs can grow to be at least the size of a softball, but they retain their best flavor when harvested smaller—around five inches in diameter. They grow well in cool weather and can be harvested well into the winter, making them a popular choice in northern regions.

Their leaves look similar to a turnip, but they're thicker and almost kale-like. They produce the typical small and yellow Brassica flower that has four cross-forming petals. This is why they fall into the designation of cruciferous vegetables.

Rutabagas taste delicious roasted, added to soups, or baked in casseroles, soufflés, and even pies. Crunchy and juicy, it's also possible to chop them up and eat them raw.

Botanical Name Brassica napobrassica
Common Name Rutabaga, Swede, yellow turnip
Plant Type Root vegetable
Mature Size Up to 2 ft. tall
Sun Exposure Full sun
Soil Type Loamy, qell-drained
Soil pH Acidic, neutral
Bloom Time N/A
Flower Color Yellow
Hardiness Zones 3 - 9, USA
Native Area Europe
Toxicity Non-toxic

Plant Care

It can take up to four months for a rutabaga to fully mature. They like to be kept cool during the maturation process, so they need to be planted later in the year in warmer regions for this to be achieved.

Light

Rutabaga will appreciate a full sun position, but they can still grow in partial shade.

Soil

Rutabagas prefer a slightly acidic soil pH in the range of 6.0 to 6.5. As with all root vegetables, good soil fertility will help them grow throughout their long season and make sure the soil is well-draining, so the bulbs don't rot.

Adding organic matter to less fertile soil is recommended.

Water

At least an inch of water per week is vital for good root development, more during particularly hot, dry weather. Rutabagas that grow in dry conditions are prone to cracking and won't develop their sweetness.

Temperature and Humidity

A little frost sweetens rutabagas. You can dig them in the fall (or late winter in warmer climates) or you can leave them in the ground with a thick layer of straw mulch and harvest as needed.

Fertilizer

If you start with soil that is rich in organic matter, you won't need any additional fertilizer. A side dressing of compost, mid-season, will give them the boost they'll need to get through to fall.

Be aware that too much nitrogen can result in deformed bulbs, so if you're using a fertilizer double-check the balance before mixing it with the soil.

Rutabaga Varieties

  • Altasweet - This variety has a mild flavor that isn't as peppery as some.
  • American purple top - A popular variety with large bulbs that have a deeper purple crown.
  • Laurentian - This variety has sweet bulbs and a uniform shape. It shares similarities with the American purple top but tends to have a smaller root.
  • Pike - Similar to ‛laurentian', pike is known to be a little hardier. It takes a little longer to mature too.

How to Grow Rutabaga From Seed

Rutabagas are direct-seeded about half an inch deep in the late spring, after danger of frost, so that they'll mature in the fall. In warm climates, they're usually seeded in the fall and grown over winter. They won't sweeten if they mature during hot weather.

Plants will need to be thinned when they're about three to four inches tall, so the bulbs will have room to fill out. If they're crowded, it can result in overly large tops and straggly roots.

The greens can be harvested any time after they reach four inches tall. Larger bulbs tend to get tough. If you don't harm the top of the bulb, the greens will continue to regrow.

Common Pests/Disease

Rutabagas are less bothered by pests than most Brassica plants, but you should still rotate your growing areas. The main disease that ruins crops is the soil-borne fungus clubroot. If your plants get clubroot, it's recommended you wait six to ten years to grow any Brassica in that area.

There are several insects, such as flea beetles, that will chew on and damage the leaves. If you plan to use the greens, a row cover will protect them.

Root maggots cause more of a problem because they damage the bulbs. The row covers will help with these, as well, by preventing the moths from laying their eggs on the leaves.