Vegetable · Apiaceae
Carrot
Daucus carota subsp. sativus
Give it deep, loose soil and steady water, and the carrot rewards you with sweet, straight roots.
Full sun
Every 3–7 days
41–77°F · 5–25°C
60–80 days
Overview
Carrots are a cool-season root crop with feathery tops and a long, sweet taproot that does all its growing underground. They belong to the same family as parsley and dill, and the wild ancestor traces back to Central Asia. The orange root most of us picture is only one option, since the crop also comes in purple, red, yellow, and white.
What makes a carrot easy or hard is the soil beneath it. Deep, loose, stone-free ground lets the root drive straight down, while heavy clay or buried rocks turn it into a forked, stubby mess. Get the bed right first and the rest of the job is mostly patience.
This is a biennial grown as an annual, which means you harvest the root in its first year and never see the flower unless a plant overwinters. Sow the seed where it will grow, thin the crowd, water without fail, and steer the crop toward cool weather for the sweetest roots.
Care
The short version: full sun in deep, loose, rock-free soil, with steady moisture of about an inch a week, seedlings thinned to give each root room, and a low-nitrogen feed worked in before you sow.
Light
Carrots want full sun, six or more hours a day, though they'll take a little afternoon shade where summers run hot. Too much shade gives you lush tops and disappointing roots.
Water
Keep the soil evenly moist, about an inch (2.5 cm) of water a week, and water deeply so it soaks the whole root zone. Let the bed swing between bone dry and soaked and you get bitter, tough, or split roots.
Soil
This is the part that matters most. Carrots need deep, loose, well-drained sandy loam cleared of rocks, clods, and debris, at a pH of 6.0 to 6.8, because anything heavy or compacted forks and stunts the root.
Temperature
Carrots are a cool-season crop, happiest between 41°F and 77°F (5°C to 25°C). They handle frost well, and a touch of cold late in the season turns starch to sugar and sweetens the root.
Humidity
Ordinary outdoor humidity suits them fine, so there's no figure to chase. What counts is even soil moisture rather than anything in the air.
Feeding
Work a low-nitrogen balanced fertilizer like 5-10-10 into the bed before you sow, with an optional side-dress at midseason. Heavy nitrogen or fresh manure backfires, pushing out forked, hairy roots.
Pruning
There's no pruning to do, but thinning is not optional. Once the tops reach about 2 inches (5 cm), thin the seedlings to 2 to 3 inches (5 to 8 cm) apart, snipping rather than pulling so you don't jostle the roots that stay.
Size & spacing
The tops stand about 8 to 16 inches (20 to 40 cm) tall, with the roots packed below. Thin each plant to 2 to 3 inches (5 to 8 cm) apart so every root has room to size up.
When to plant
Carrots like it cool and grow best at the shoulders of the season. Sow the first round a couple of weeks before the last spring frost, keep sowing every few weeks into midsummer, and the roots come ready from early summer through fall, sweeter for any frost they catch.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Direct sow outdoors 2-3 weeks before the last spring frost once soil is workable and at least 7°C (45°F); succession sow every 2-3 weeks through midsummer for a fall crop
- Harvest: Harvest roots at any usable size, typically 60-80 days after sowing; fall crops can stay in the ground into cool weather, which improves sweetness. Flowers only appear in the second year if roots are overwintered.
Hardiness
USDA hardiness zones: 3–10
Temperature: down to -40°C
Troubleshooting
Most carrot problems hide underground until you pull a root, so the tops rarely warn you in time. Learn to read the few that do, and dig a sample when something looks off. Match what you find below, then fix the bed before the next sowing.
Rusty tunnels boring through the roots
Those grimy tunnels packed with rust-colored frass are the work of carrot rust fly larvae, though cleaner round holes point to wireworms instead. Light damage trims away, but badly riddled roots belong in the bin. Cover the bed with floating row cover from sowing, rotate away from last year's carrot patch, and hold off sowing until the first egg-laying flight has passed.
Fix:
- Harvest promptly and discard heavily damaged roots
- Cut away lightly damaged tissue and use the remainder
Yellow, twisted new growth with bushy, hairy roots
This is aster yellows, a phytoplasma that leafhoppers carry from plant to plant. The inner leaves yellow and contort while the outer ones flush red, and the root turns bitter and grows a beard of hairy side roots. There's no cure, so pull and destroy any infected plant, then keep leafhoppers off with row cover and clear out nearby weed hosts.
Fix:
- Remove and destroy infected plants; there is no cure
Bitter, tough, or undersized roots
Carrots turn bitter and woody when watering runs hot and cold or the row never gets thinned. Crowded seedlings choke each other into thin, tangled roots, and a heat wave during root sizing only makes the flavor worse. Get back to a steady inch of water a week, thin to 2 to 3 inches (5 to 8 cm) apart, and aim the crop at cool weather.
Fix:
- Resume deep, even watering of about 2.5 cm (1 in) per week
- Thin remaining seedlings to 5-8 cm (2-3 in) apart
Forked, twisted, or misshapen roots
When the taproot hits a rock, a clod, or compacted ground, it splits and grows crooked around the obstacle. Fresh manure or too much nitrogen does the same by pushing out forked, hairy roots, and root-knot nematodes can be the culprit too. Loosen the bed deeply and pull out the rocks before you sow, and the next crop comes up straight.
Fix:
- Harvest and use affected roots normally; flavor is unaffected by simple forking
- Deeply loosen and rake the bed, removing rocks and clods, before the next sowing
Green tops on the shoulders of the root
Green shoulders form when the crown of the root pokes above the soil and catches the sun. It's only the top inch or so, and the rest of the carrot is perfectly good once you trim the green away. Hill a little soil or mulch over the crowns as the roots swell and the problem never starts.
Fix:
- Trim off the green portion before eating; the rest of the root is fine
Toxicity
Carrots are about as safe as a garden plant gets. Both the root and the leafy tops are food, with nothing toxic to pets, livestock, or children. The only thing to watch is a large raw chunk, which can be a choking hazard, so cut it down for small mouths.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Carrot is safe for cats, and a little cooked or grated raw makes a harmless treat. Cats rarely care for it, and the only risk is a choking hazard from a big raw chunk, so cut it small.
Dogs None
Dogs can eat carrot with no trouble at all, raw or cooked. Many enjoy a whole cold one as a low-calorie chew. Slice large pieces down so they go easy on the teeth.
Horses None
Carrots are a classic horse treat and cause no harm in sensible amounts. Break them into long strips rather than coin-shaped rounds, which can lodge in the throat, and keep the helpings modest for an easy keeper.
Rabbits None
The leafy tops are the better food for a rabbit, since the root is high in sugar and best given only as an occasional nibble. Nothing here is toxic, just rich, so go light on the orange part.
Livestock None
Cattle, goats, sheep, and pigs all take to carrots and their tops without any poisoning risk. Introduce them gradually and chop them up so a greedy animal doesn't choke on a whole root.
Birds None
Backyard hens and parrots can eat carrot freely, and the bright flesh is a good source of vitamin A. Grate or finely chop it so smaller birds can manage, and the feathery tops are fair game too.
People None
Carrots are an everyday vegetable, eaten raw or cooked by all ages with nothing to watch for. Eating a great many over time can tint the skin faintly orange, which is harmless and fades on its own.
No special handling required.
Varieties
Carrots come in shapes for every kind of soil, from long supermarket types to stubby roots that shrug off heavy ground. These are the ones worth knowing by name.
Danvers 126
A tapering carrot of about 6 to 7 inches (15 to 18 cm) that copes with heavier ground far better than the long slender types.
Scarlet Nantes
The classic home-garden carrot, with sweet, crisp, cylinder-shaped roots that end in a blunt tip and eat beautifully fresh.
Imperator types
The long, tapered carrots you see in the supermarket, which only grow straight in deep, loose, stone-free soil.
Red Cored Chantenay
A stocky, broad-shouldered carrot that does well where the soil is shallow or heavy and longer roots would struggle.
Thumbelina
A small round carrot that thrives in pots and in the clay or rocky beds where ordinary roots fork and stall.
Companions
Carrots do best beside onion-family plants that throw off the carrot rust fly, and quick crops like radish that share the row while the slow seed germinates.
Plant near
onion: Onion-family plants interplanted with carrots are traditionally used to help deter carrot rust fly
leek: Like onions, leeks are used in extension companion guides to help confuse and deter carrot rust fly
radish: Fast-germinating radishes sown beside slow carrots mark rows and save space; cited as a space-saving intercrop by UMN Extension
lettuce: Shallow-rooted lettuce shares bed space without competing with the deep carrot taproot
Keep apart
dill: Some extension companion guides advise keeping dill away from maturing carrots; the related species may cross-react and dill can attract pests of the carrot family
How to propagate
There's only one way to make more carrots, and that's from seed sown straight into the ground, because the taproot won't tolerate being moved.
SeedEasy
Early spring through midsummer, once soil is at least 7°C (45°F) · Germination in 1-3 weeks; roots reach usable size in about 60-80 days
Carrots only ever come from seed sown straight into the bed, since the taproot won't survive a move. Sow about a quarter inch (6 mm) deep from early spring through midsummer once the soil hits 45°F (7°C), and keep the surface damp the whole 1 to 3 weeks it takes to sprout, which is slow enough to test your patience. From there the roots fill out to eating size in roughly 60 to 80 days.
Myths
You can start carrots indoors and transplant the seedlings out like tomatoes.
Moving a young carrot disturbs the slender taproot just as it's trying to drive straight down, and the result is a forked or stunted root. Carrots want to be sown right where they'll grow, thinned in place rather than shifted.
Every carrot has to come out of the ground before the first frost or it's ruined.
A light frost doesn't bother fall carrots at all. The cold actually turns starch to sugar, so the roots taste sweeter the longer they sit in cool soil, and in many areas you can keep digging them well into late fall.