Swedish turnip Brassica napus (Napobrassica Group)

Brassica napus (Napobrassica Group) is referred to rutabaga in the United States.  The genus name Brassica is Latin for cabbage.  Rutabaga is a cross between turnips and cabbage.  It is not a widely used vegetable in the US due to the length of time needed to mature.  It can take 3 to 4 months to reach maturity, where their cousin plant, the turnip, can be grown in approximately half the time.  However, rutabaga tends to be larger, denser and sweeter than a turnip.

This cool-weather biennial is grown as an annual.  Sow seeds in your garden 4 to 6 weeks before the last frost date.  It can also be sown after the summer heat has dissipated for a fall or early winter harvest.  

The edible bulb is at its best when harvested when 3-5" in diameter.  Bulbs exceeding 5" can tend to be tough.  The greens or foliage can be harvested once they reach a height of 4".  Providing the top of the bulb is not damaged when harvesting the greens, the bulb will continue to form new growth.  

Ensure that your plants receive 1" of water per week.  Drought conditions can make the plant woody and bitter tasting.  On the other hand, your harvest will have more flavor, be firmer and store better after a dry season than a wet one.  

There are several varieties available.  They include:

• Altasweet, which has a mild flavor, less peppery flavor than other varieties.  They can take 90 to 100 days to maturity.  
• American Purple Top, a popular variety.  It has large bulbs and maturity ranges from 90 to 100 days.
• Laurentian,  is a sweet tasting Heirloom.  Maturity can be a bit longer, 90 to 120 days.
• Pike is very similar to Laurentian, however, somewhat hardier.  100 to 120 days to maturity.

Insects, Diseases, and Other Plant Problems:  The largest issue is clubroot, a soil-born disease.  Should clubroot make a presence, avoid planting rutabaga in that location for at least 6 years.  

Flea beetles can damage the leaves.  Providing a row cover can help protect the greens.  A row cover can also help prevent moths from laying eggs on the leaves.