Rutabaga is also called Swedish turnip. It is similar to turnip in that it is a cool-season crop with a crunchy underground root, though rutabagas produce a larger, firmer, rounder edible root than turnips. Rutabaga flesh is yellow and has a finer texture than turnips. Frost typically sweetens maturing rutabagas, so these productive crops are harvested late in the season and enjoyed in autumn. Pick greens when thinning plants early in the season and add the tasty leaves to salads.
Rutabagas are a long-growing crop that are great for pairing with early spring greens and vegetables. Planted in early summer, rutabagas will fill in empty garden space left by spring peas, broccoli, lettuce, radishes, and spinach, all of which finish their growing season prior to rutabagas putting on significant growth. In mild winter climates, rutabagas can be grown over winter, making them an excellent planting partner for warm-season plants, such as tomatoes and peppers. When the warm-season plants finish producing fruit, rutabagas begin to grow and fill the space left when the warm-season plants are composted.
Rutabagas grow well in full sun and moist, well-drained soil. A root crop, rutabagas demand quick-draining, loose soil for best root production. Plant rutabagas in raised beds if your garden soil is clay or boggy. Plant rutabaga seeds directly in the garden. The young, delicate roots are tricky to transplant. In mild winter areas, sow seeds in mid- to late summer so the crop reaches maturity when temperatures cool in late fall or winter. Rutabagas typically require 12 to 16 weeks to reach maturity.
In cold winter areas, plant rutabaga seeds in summer. Aim for a planting date that is about 12 weeks before the first predicted fall frost. Rutabagas will tolerate a light frost, and cool weather brings out their sweet flavors. A thick layer of mulch spread over the soil surface in late fall will prevent the roots from freezing and extend the harvest by a couple of weeks.
Sow rutabaga seeds 2 inches apart and ½ inch deep in rows 12 inches apart. When seedlings are several inches tall, thin them to stand 6 inches apart so roots have room to grow. Use the greens from the thinned seedlings in salads.
Rutabagas are ready to harvest when they are between tennis ball and softball size. Roots larger than a softball are generally tough and lacking in flavor. Several light frosts will bring out sweet flavors, so don't hesitate to leave roots in the ground for additional days at the end of the season. Harvest rutabagas by gently pulling them or lifting them out of the ground with a digging fork.