Vegetable · Brassicaceae
Turnip
Brassica rapa subsp. rapa
Sown cool, watered even, and pulled young, the turnip fills out into round white roots and a crown of green tops in one short season.
Full sun
Every 3–7 days
41–77°F · 5–25°C
40–60 days
Overview
Turnip is a cool-season root in the brassica family, close in form to cabbage and mustard. Grown for ages for both the swollen white root and the leafy green tops, it fills out fast in the ground, its rosette of foliage rising a foot or so above a root that rounds and thickens below the surface. From a spring or late-summer sowing the green tops stand cuttable in about a month, with the roots swelling not long after.
The plant is a biennial, packing its first-year growth into that pale storage root and only flowering the year after, though gardeners lift it as a fast annual well before any bloom appears. The root holds its crisp, dense white flesh best when it sizes up in cool weather, since heat coarsens it, which is why midsummer is the one stretch to plan around. Sown into the cool shoulders of the season, the root stays smooth-skinned and firm.
Most of the character comes down to timing and thinning. In loose, evenly moist ground the root fills out round and mild, its flesh crisp and close-grained under a thin white skin often washed purple across the shoulders that catch the light. Let the soil dry and then flood, or hold the root too long in warm ground, and that clean flesh gives way to woody, sharp-flavored roots, spongy and stringy where they should be dense.
Care
The short version: turnips want full sun and loose, rock-free soil, with about an inch of water a week to keep moisture even and the flesh crisp. The seed goes in direct in cool weather, the seedlings thin to give each root room to round out, and the harvest comes young, before heat or a hard frost, while the roots are still smooth and white.
Light
Turnip colors and fills out best in full sun and takes a little partial shade. The green tops stay leafy in some shade, while the root rounds out faster and fuller, its white flesh denser, under a long stretch of direct light.
Water
Turnip wants about 1 inch (2.5 cm) of water a week, kept even. That steady moisture holds the root flesh crisp, tender, and mild, while a swing from dry soil to a heavy soaking leaves it pithy, cracked across the skin, or harsh.
Soil
Turnip roots run smooth in loose, well-drained loam free of rocks and fresh manure, both of which fork and scar the tender skin. A pH from 6.0 to 7.5 suits it, and near-neutral ground also helps hold clubroot, with its lumpy galls, at bay.
Temperature
This is a cool-weather crop, its flesh at its crispest from about 41°F to 77°F (5°C to 25°C). Roots that swell in heat turn woody and sharp, so the sowings fall in spring and fall rather than midsummer.
Humidity
Ordinary outdoor air is all turnip needs, so there is no level to manage. Even soil moisture matters far more to the firmness of the root than anything happening in the air.
Feeding
A balanced granular feed such as 10-10-10 works into the bed before sowing, guided by a soil test. Nitrogen stays light, since too much throws lush green tops at the expense of the swelling root.
Pruning
Turnip needs no pruning. The seedlings thin to 3 to 6 inches (8 to 15 cm) apart once they stand a few inches tall, and the outer green leaves pick at 4 to 6 inches, the growing point left so fresh tops push back up.
Size & spacing
The leafy plant stands about 12 to 18 inches (30 to 45 cm) tall and 6 to 12 inches (15 to 30 cm) wide. Thinned to 3 to 6 inches (8 to 15 cm) apart in rows 18 to 30 inches (45 to 75 cm) apart, each root finds the room to round out and swell.
When to plant
Turnip fills out in cool weather and stalls when the soil turns warm. The seed goes into the bed in early spring as soon as the ground can be worked, and again in late summer for a fall crop. The round roots come up young, ahead of summer heat or a hard freeze, while their white flesh is still crisp, and a light fall frost only sweetens what stays in the ground.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: direct sow in early spring as soon as soil can be worked (around mid-April in the Upper Midwest), and again in late summer (around August 1) for a fall crop
- Harvest: harvest roots at about 2-3 inches in diameter before hot weather or hard freezes; flavor sweetens after light fall frost; greens harvestable at 4-6 inches tall
Hardiness
USDA hardiness zones: 2–9
Temperature: down to -46°C
Troubleshooting
Most turnip trouble shows plainly, either in pitted, holed green leaves above ground or in the swollen white root below, and the brassica pests mark young seedlings worst. The earliest signs are the easiest to read and settle, often with a row cover or a shift in timing. Match the look below to what the plant shows and act while the seedlings are still small.
Limp, sagging seedlings above brown-bored, riddled roots
A seedling goes limp and sags to the ground, and lifting it turns up a root laced with winding brown tunnels and small white grubs, soft and legless, curled in the flesh. Those grubs are the larvae of the cabbage root maggot, a fly that lays its eggs right at the soil line, while wireworms leave a similar bored track in ground lately turned from sod. The tunneled plants are dug out and destroyed, fresh seed goes under a row cover pressed tight to the soil at the edges, and staggered sowing dates carry the next planting past the thick of the egg-laying.
Fix:
- Remove and destroy infested plants and roots
- Re-sow under floating row cover sealed at the edges
- Delay or stagger sowing to miss peak fly egg-laying
Sallow, dwarfed plants above warped, swollen root galls
Above ground the plant reads wrong, held small with leaves gone sallow and yellow, drooping through the warm hours of the day. Lift it and the root shows the reason: clubroot, a soilborne disease that swells the root into lumpy, club-shaped knots and galls in place of a clean round bulb. A root that misshapen cannot recover, so the whole plant comes out with the soil clinging to it and stays clear of the compost. That bed then rests from brassicas for several years, and lime lifts the soil toward neutral before the family goes back in.
Fix:
- Remove and discard infected plants with surrounding soil (do not compost)
- Stop growing brassicas in that bed for several years
- Raise soil pH toward neutral with lime before replanting brassicas
Leaf blades speckled with minute, clean-edged round holes
The green leaf blades come up stippled with small round pits and clean-edged holes, as if peppered by fine shot. That look is the mark of flea beetles, tiny beetles with a hard, shiny black shell that spring off the foliage the instant a hand comes near. They chew the young spring and fall seedlings worst, so a floating row cover goes over each new sowing, steady water carries the little plants up past the damage, and the weedy mustards that shelter the beetles get pulled from nearby ground.
Fix:
- Cover new sowings with floating row cover at seeding
- Keep plants growing fast with steady water so they outgrow damage
- Remove nearby weedy mustards that host the beetles
Root flesh gone corky and stringy with a burning sharp taste
Draw a knife through the root and the cut face tells the tale: spongy white pith riddled with air and a stringy, fibrous grain where crisp, dense flesh belongs. This coarse texture comes down to heat and timing, not disease, since roots that swell in warm weather, hold in the ground past their size, or ride out a jump from dry soil to soaking all turn woody and sharp on the tongue. What is left comes up at 2 to 3 inches (5 to 8 cm) across, any tender leaf tops cook down as greens, and a late-summer sowing brings the next roots to size in the cool of fall.
Fix:
- Harvest remaining roots promptly at 2-3 inches diameter
- Use affected roots' tops as cooking greens if still tender
- Re-sow in late summer so roots mature in cool fall weather
Toxicity
Turnip is food from white root to green leaf and safe for people and pets alike. Both the root and the greens are eaten with no special handling, and the plant is not listed as toxic to cats or dogs. The one footnote is grazing livestock, where weeks of heavy raw brassica forage can have a mild effect, which never comes up at garden scale.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Turnip is safe for cats, so a nibble of the pale cooked root or a shred of green leaf does no harm. As meat eaters, most cats sniff once and turn away.
Dogs None
No toxin sits in turnip for dogs. A little plain cooked root, soft and white, makes a fine occasional snack, kept small, since a big serving of any vegetable can loosen the stomach.
Horses None
Both the firm root and the leafy tops are safe for horses. Large roots are cut into chunks so a whole round one cannot lodge in the throat.
Rabbits None
The leafy green tops and a little of the crisp root are safe for rabbits. The greens come in slowly, the way any new fresh food would.
Livestock None
Turnip roots and leafy tops make sound forage with no poison in them. The one caveat is grazing, since weeks of heavy raw brassica greens can nudge thyroid function and bring mild bloating, which never arises at home-garden amounts.
Birds None
Chickens and other backyard birds peck happily at the green tops and chopped white root, and every bit of it is safe for them.
People None
Turnip is a kitchen vegetable from white root to green leaf. The roots roast or mash and the greens cook down like any other cooking green, with no part set aside.
No special handling needed. Like other brassicas, very large raw quantities can cause gas, and goitrogenic compounds in brassica forage are mainly a concern for livestock grazed heavily on it, not for household pets or people eating normal amounts.
Varieties
Turnips range in look from round white globes to golden-fleshed roots and the leafy greens types. These are the ones seen most often.
Purple Top White Globe
The classic heirloom the mind reaches for, a round white globe of a root washed purple across the shoulders that rise into the light, carrying a full head of green tops.
Hakurei
A quick salad turnip whose small white roots come up smooth-skinned and round, their flesh mild and sweet enough to slice raw into a salad.
Golden Ball
A heirloom that takes about 60 days to fill out, its round root cut open to reveal warm yellow flesh with a mild, faintly sweet flavor.
Seven Top
Grown for a thick stand of green leafy tops rather than the root, which stays small, hard, and woody and is best left down in the soil.
Just Right
A hybrid that raises green tops in about 28 days and smooth white roots in roughly 60, so a single sowing yields both.
Companions
Turnips do best next to cool-season plants that share their schedule without sharing their pests, and worst beside their own brassica cousins, which trade flea beetles, root maggots, and clubroot back and forth.
Plant near
peas: Cool-season legume sown on the same early-spring schedule; fixes nitrogen and does not compete heavily with the shallow turnip bed
onions: Alliums make compact, pest-light neighbors in the root bed and are not hosts for brassica pests
Keep apart
cabbage and other brassicas: Closely related cole crops share flea beetles, root maggots, and clubroot; clustering or rotating them in the same bed builds up these pests and diseases
How to propagate
Turnip rises straight from seed sown where it will mature, since a lifted root sulks and checks. The small round seed and a patch of loose soil are all it takes.
SeedEasy
Direct sow in early spring as soon as the soil can be worked, and again in late summer (around August 1) for a fall crop; turnips do not transplant well and succession sowings every 10 days extend harvest · Seedlings emerge in about 10 days; greens are cuttable in about 4 weeks and roots reach harvest size in roughly 40-60 days
Turnips rise straight from seed sown where they will mature, since a lifted root sulks and checks. The small seed drops a quarter to half an inch (0.5 to 1 cm) deep, an inch or two apart, in rows 18 to 30 inches (45 to 75 cm) apart, then the seedlings thin to 3 to 6 inches (8 to 15 cm), the pulled thinnings eaten as tender greens. Pale sprouts break the surface in about 10 days, the green tops stand ready to cut in roughly 4 weeks, and the roots round out in 40 to 60 days. A fresh row every 10 days keeps young roots coming.
Myths
A rutabaga is only a turnip going by a different name.
They are two separate crops with a different look. The turnip is Brassica rapa, forming quick-growing roots that are usually white-fleshed, while the rutabaga is Brassica napus, its larger roots holding yellow flesh and wanting a longer season and more room. The two are sown and spaced as the different plants they are.
The moment frost brushes the garden, any unharvested turnip is spoiled.
A light fall frost does the opposite and sweetens the roots waiting in the ground. Only a hard freeze truly harms roots left in the soil, so the harvest comes ahead of a hard freeze, not ahead of the first light one.
Turnips are only a fall crop.
Turnips are a cool-season vegetable with two sowing windows, one in early spring as soon as the soil can be worked and another in late summer for a fall harvest. The one thing to avoid is letting the roots swell in the heat of midsummer.