How to Grow Rutabaga

What a Rutabaga Is

Rutabaga (also called swede) is a large, yellow-fleshed root vegetable in the brassica family, closely related to turnips but slower-growing, denser, and sweeter after cold weather. Both the University of Minnesota Extension and Utah State University Extension cover it alongside turnips as a classic cool-season home garden root crop.

Compared with a turnip, a rutabaga needs a longer season and more room, and it rewards that patience with a root that stores through much of the winter. If you have grown turnips successfully, rutabaga is the same playbook shifted later and larger.

When to Plant: Think Fall Crop

Utah State University Extension is direct about timing: rutabagas should be seeded in the summer and grown as a fall crop, because they develop slowly, need time to fill out the root, and do not withstand summer heat as well as turnips. Seeds germinate well across a wide 60 to 85 F soil temperature range, so summer sowing is not a germination problem - the point is to have the root-bulking phase land in cool weather.

USU notes that root development occurs best when temperatures are below 75 F. In cooler climates rutabaga can also work as a spring-sown crop, but for most gardens the summer-sown, fall-harvested schedule produces the best roots. Count backward roughly 60 to 80 days (USU's maturity figure) from when you want mature roots in autumn to find your sowing date.

Sowing, Spacing, and Soil

Sow seed 1/4 to 1/2 inch deep, per Utah State University Extension. Because rutabaga seed is small and germination is usually strong, sow a little thick and thin ruthlessly: USU recommends thinning to 4 to 6 inches between plants in rows 18 inches apart, noting rutabagas need wider in-row spacing than turnips to accommodate the larger root. Crowded rutabagas make lush tops and skinny roots.

Site and soil: a sunny location with fertile, deep, well-drained soil, improved with plenty of organic matter and an all-purpose fertilizer worked in before planting (USU). Like all brassicas, rotate rutabaga away from beds that recently grew cabbage-family crops.

✔ Thin on time and to the full spacing. Skipping the thinning step is the single most common reason home-garden rutabagas come out as all leaves and no root.

Water and Feeding

Water rutabagas regularly, applying 1 to 2 inches per week depending on temperature and soil type (Utah State University Extension). Steady moisture matters more here than with leafy crops: USU warns that moisture fluctuations cause root disorders such as cracking, woody roots, and pithiness, and contribute to bitter flavors.

For fertility, USU recommends side-dressing with about 1/4 cup of a nitrogen fertilizer (21-0-0) per 10 feet of row around 6 weeks after emergence. Avoid heavy nitrogen late in the season, which favors tops over roots.

Harvest and Storage

Roots mature about 60 to 80 days from seeding, and Utah State University Extension says to start harvesting when roots reach about 4 inches in diameter. Rutabagas are quite tolerant of light frosts, and cool weather at maturity improves both texture and sweetness, so there is no rush to clear the bed at the first chill - harvest before the ground freezes hard.

For storage, USU recommends washing the roots and holding them in cool, moist conditions - 35 F and 95 percent relative humidity - where they will keep for 3 to 4 months. A refrigerator, a cold cellar, or a buried container in cold climates all approximate these conditions.

Common Problems

Rutabaga shares pests with the rest of the cabbage family. Utah State University Extension lists aphids, cabbage worms, and flea beetles among the insect problems, plus Alternaria leaf spot on foliage. Floating row cover from sowing onward blocks most of the insect pressure on this crop, and fall timing itself helps, since pest populations decline as weather cools.

Quality defects - cracked, woody, pithy, or bitter roots - trace back mostly to uneven watering or to growing the crop through heat, both covered above. If your rutabagas repeatedly disappoint, fix the schedule and the irrigation before blaming the variety.

Sources

Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.

• Utah State University Extension — How to Grow Rutabagas and Turnips in Your Garden — Seed in summer as a fall crop; germination 60-85 F; root development best below 75 F; seed depth 1/4-1/2 inch; thin to 4-6 inches in rows 18 inches apart; 1-2 inches water/week; moisture swings cause cracking, woodiness, pithiness, bitterness; 1/4 cup 21-0-0 per 10 ft row 6 weeks after emergence; 60-80 days to maturity; harvest at 4-inch diameter; tolerant of light frosts; store at 35 F and 95% RH for 3-4 months; pests aphids, cabbage worms, flea beetles, Alternaria leaf spot.
• University of Minnesota Extension — Growing turnips and rutabagas in home gardens — Rutabagas are grown alongside turnips as a cool-season brassica root crop for home gardens; supports the general cool-season framing and brassica-family rotation guidance.

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