Carrot
Daucus carota subsp. sativus
A crop with two requirements and very little else to it: deep stone-free soil, and protection from carrot fly. Get those right and carrots are undemanding. Get the soil wrong and they fork; skip the mesh and they are tunnelled through by the time you lift them. Carrots also resent transplanting absolutely, so they are always sown where they are to grow.
- Position
- Full sun or Partial shade
- Water
- moderate demand
- Drainage
- Free-draining
- Grows to
- 30–45 cm × 15 cm
- Hardiness
- H5
- Harvest
- June to November
- Difficulty
- Some care needed
Described view
A bed of carrot seedlings under insect-proof mesh held clear on hoops and tucked into the soil at the edges
August
Harvest
Carrot’s year
Resolved for United Kingdom (general). Every window is stored against a climate event rather than a date, so a late frost pocket runs later than the band shows. What else August calls for.
| Activity | J | F | M | A | M | J | J | A | S | O | N | D |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sow outdoors | March. | April. | May. | June. | July. | |||||||
| Harvest | June. | July. | August. | September. | October. | November. |
Timing that travels
The band above resolves this plant's windows into months for one region. These are the windows themselves, stored against a climate event rather than a date — which is the form that survives being carried to a colder garden, a frost pocket, or next year.
- Sow outdoors0–16 weeks after the soil becoming workable, successionally, every three or four weeks
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Carrots — sowing
Checked 2026-08-13
Carrots are always sown direct. They will not transplant.
- Germination2–19 weeks after the soil becoming workable, 14–21 days
source
Sourced guidancehigh confidence
- OSU Extension Service — Oregon State University: Seed germination — carrot
Checked 2026-08-13
Conditions it needs
- Light
- Full sun, Partial shade
- Direct sun
- 5 hours a day or more
- Frost
- Hardy
- Hardiness rating
- H5 (RHS)
- Grows best at
- 16–21 °C
- Germinates at
- 7–25 °C
- Soil
- Sandy, Loam, Silt
- Soil pH
- 6–7
- Drainage
- Free-draining
- Water needs
- moderate
- Drought
- moderate toleranceHorticultural consensusDepends on conditions
- Waterlogging
- poor tolerance
- Heat
- moderate tolerance
- Wind and exposure
- good tolerance
Where these figures come from
- LightSourced guidancehigh confidence
- Royal Horticultural Society: Grow your own: carrots
Checked 2026-08-13
- Direct sunHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- FrostSourced guidancehigh confidence
Roots can be left in the ground over winter in mild areas under a covering of straw.
- Royal Horticultural Society: Carrots — hardiness
Checked 2026-08-13
- Hardiness ratingSourced guidancehigh confidence
- Royal Horticultural Society: RHS hardiness ratings
Checked 2026-08-13
- Grows best atHorticultural consensusmoderate confidence
- Home and Garden Information Center — Clemson Cooperative Extension: Carrot — culture
Checked 2026-08-13
- Germinates atSourced guidancehigh confidence
Germination is slow — often two to three weeks — and slower still at the cold end of the range.
- OSU Extension Service — Oregon State University: Vegetable seed germination temperatures
Checked 2026-08-13
- SoilSourced guidancehigh confidence
Light, deep, stone-free soil. Heavy clay and recently manured ground both cause forking.
- Royal Horticultural Society: Carrots — soil
Checked 2026-08-13
- Soil pHSourced guidancehigh confidence
- University of Minnesota Extension — University of Minnesota: Soil pH for vegetable crops
Checked 2026-08-13
- DrainageHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Water needsHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- DroughtHorticultural consensusDepends on conditionsmoderate confidence
Applies when: Established carrots root deeply and cope; irregular watering during growth causes the roots to split.
No external citation — see the evidence type above.
Checked 2026-08-13
- WaterloggingHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- HeatHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Wind and exposureHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
On your soil
Computed by comparing this plant's recorded requirements against each soil's recorded characteristics. A recorded horticultural fact overrides the comparison where GrowingHQ holds one.
| Soil | Verdict | Why |
|---|---|---|
| Heavy clay | Works, with one condition | A carrot's problem on clay is mechanical rather than chemical. The taproot has to push through the soil to make a straight root, and on heavy ground it forks, stumps or stalls — which no amount of feeding or pH correction affects. The soil is otherwise perfectly fertile for it.Grow short, stump-rooted cultivars rather than long ones, or grow in a deep container or a raised bed of loose soil. Do not add fresh manure — it makes forking worse rather than better. |
| Sandy | Prefers this soil | Sandy suits Carrot as it stands: The pH suits it: it wants 6 to 7, and this soil is in that range. The free drainage is exactly what it wants. Sandy soil is among the soils it is recorded as suiting. There is ample rooting depth for it. |
| Chalky and alkaline | Works, with one condition | Carrot will crop on chalky and alkaline, but one thing has to be dealt with first. The soil is substantially too alkaline for it: it wants pH 6 to 7, and this soil sits around 7.8 to 8.5.The pH is the obstacle. Small shifts are achievable and slow; large ones are not. On chalky and alkaline the dependable answer is a container of the right compost rather than an attempt to change the ground. |
| Loam | Prefers this soil | Loam suits Carrot as it stands: The pH suits it: it wants 6 to 7, and this soil is in that range. The free drainage is exactly what it wants. Loam is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering. There is ample rooting depth for it. |
| Silty | Prefers this soil | Silty suits Carrot as it stands: The pH suits it: it wants 6 to 7, and this soil is in that range. The free drainage is exactly what it wants. Silt is among the soils it is recorded as suiting. The soil holds moisture, which saves a great deal of watering. There is ample rooting depth for it. |
| Peaty and acid | Works, with one condition | Carrot will crop on peaty and acid, but one thing has to be dealt with first. It needs ground that drains, and this soil holds water. A plant that stays in the ground through winter with its roots in cold, saturated soil rots — which is what kills most of what fails on heavy ground, rather than the cold.Improve the drainage before planting — a raised bed, or bulky organic matter worked in over several seasons. Do not add sand to clay in small quantities; it makes the problem worse. |
| Shallow over rock | Works, with one condition | The root reaches rock and stops or forks. This is not a soil quality problem and cannot be improved away — the stones and the rock are the soil.A container at least 30 cm deep, or a raised bed of stone-free soil. Short-rooted cultivars in the ground will produce something; long-rooted ones will not. |
| Made ground and urban soil | Works, with one condition | Buried rubble does to a carrot exactly what stones do, and made ground is unpredictable — one bed may be clean and the next full of mortar. The failure is not visible until the crop is lifted.A container or a raised bed of imported soil. Sieving an open bed is possible for one season's carrots and rarely worth repeating. |
Not sure which you have? Four hand tests will settle it.
Space and spacing
- Mature height
- 30–45 cm
- Mature spread
- 15 cm
- Rooting depth
- 30–45 cm
- Spacing
- 5–8 cm apart
- Row spacing
- 15–30 cm
Where these figures come from
- Mature heightHorticultural consensusmoderate confidence
Foliage height; the crop is below ground.
No external citation — see the evidence type above.
Checked 2026-08-13
- Mature spreadHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Rooting depthSourced guidancehigh confidence
- USU Extension — Utah State University: Vegetable rooting depths
Checked 2026-08-13
- SpacingSourced guidancehigh confidence
Achieved by thinning, or better by sowing thinly enough not to need to.
- Royal Horticultural Society: Carrots — thinning
Checked 2026-08-13
- Row spacingSourced guidancehigh confidence
- Royal Horticultural Society: Carrots — spacing
Checked 2026-08-13
In a container
- Minimum volume
- 20 litres or more
- Minimum depth
- 30 cmSourced guidanceDepends on conditions
Where the container figures come from
- Minimum volumeHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Minimum depthSourced guidanceDepends on conditionshigh confidence
Applies when: For maincrop cultivars. Short-rooted and round cultivars — Chantenay, Paris Market types — crop well in 15–20 cm, and are the right choice for a shallow trough.
- Royal Horticultural Society: Carrots in containers
Checked 2026-08-13
A deep pot of fresh compost is also the simplest way to sidestep both stony soil and carrot fly at once, if it is stood clear of the ground.
Where and how you can grow it
Each way of growing is assessed separately, and “not assessed” is a real answer rather than a gap we have filled in with a guess.
| Method | Suitability | What it needs |
|---|---|---|
| Raised bed | Well suitedsourceSourced guidancehigh confidence
Checked 2026-08-13 | At least 30 cm of depth for maincrops; Mesh coverA raised bed lets a grower on clay have the deep loose soil carrots need without changing the whole plot. |
| Container | Well suitedsourceSourced guidancehigh confidence
Checked 2026-08-13 | 30 cm deep for maincrops, 15–20 cm for short cultivars |
| Polytunnel | Well suitedsourceSourced guidancemoderate confidence
Checked 2026-08-13 | |
| Open ground | WorkableSourced guidanceDepends on conditionshigh confidenceApplies when: Excellent on light stone-free soil, poor on clay or stony ground where the roots fork and stub.
Checked 2026-08-13 | Deep, stone-free, unmanured soil; Insect-proof mesh against carrot fly |
| Traditional dug bed | WorkablesourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | Deep cultivation, no fresh manure |
| Greenhouse | WorkablesourceSourced guidancemoderate confidence
Checked 2026-08-13 | |
| Hydroponics | MarginalsourceGrowingHQ editorial positionmoderate confidence Carrots need a deep, loose, uniform rooting medium to produce a straight root, which is exactly what channel and water-culture systems cannot provide. A medium bed deep enough to grow a decent carrot is a container of compost with pumps attached.
Checked 2026-08-13 | |
| Aquaponics | MarginalsourceSourced guidancehigh confidence
Checked 2026-08-13 | |
| Windowsill | Not suitablesourceHorticultural consensusmoderate confidence Neither the depth nor the light a root crop needs. No external citation — see the evidence type above. Checked 2026-08-13 | |
| Vertical growing | Not suitablesourceHorticultural consensusmoderate confidence Rooting depth cannot be provided in a stacked planter. No external citation — see the evidence type above. Checked 2026-08-13 |
Growing it
- SowingSow thinly, about 1 cm deep, directly where the plants are to grow. Sowing thinly is not tidiness — it removes the need to thin, and thinning is what draws carrot fly in.1–1.5 cm
- ThinningIf thinning is necessary, do it on a still, damp evening, remove the thinnings from the plot entirely, and water afterwards to settle the disturbed soil. Crushed carrot foliage is what the flies navigate by.
- ProtectionCover the bed with insect-proof mesh from sowing until harvest, tucked in at the edges. This is the single most effective thing a home grower can do for a carrot crop.
- WateringWater evenly. A dry spell followed by heavy watering makes the roots split as they take up water faster than the skin can grow.
Where this guidance comes from
- SowingSourced guidancehigh confidence
- Royal Horticultural Society: Carrots — sowing
Checked 2026-08-13
- ThinningSourced guidancehigh confidence
- Royal Horticultural Society: Carrot fly
Checked 2026-08-13
- ProtectionSourced guidancehigh confidence
- Royal Horticultural Society: Carrot fly — control
Checked 2026-08-13
- WateringHorticultural consensusmoderate confidence
- Royal Horticultural Society: Carrots — watering
Checked 2026-08-13
Is it worth putting under cover?
Whether it will grow there is on the methods table above. This is whether the space is well spent, which is a different question and usually the one being asked.
| Structure | What protection is worth | What decides it |
|---|---|---|
| Greenhouse | Extends the seasonsourceGrowingHQ editorial positionmoderate confidence What protection is worth for this crop, judged against the same standard as every other record in this file.
Checked 2026-08-13 | Rooting depth. A greenhouse border grows a fine early carrot and a bench does not, because a pot deep enough is a pot nothing else fits in.The second benefit is one nobody plans for: a closed structure excludes carrot fly, which is otherwise the crop's defining problem. |
| Polytunnel | Extends the seasonsourceGrowingHQ editorial positionmoderate confidence What protection is worth for this crop, judged against the same standard as every other record in this file.
Checked 2026-08-13 | Rooting depth, which a tunnel bed has and a greenhouse bench does not. This is one of the clearer cases where the cheaper structure is the better one. |
Growing it without soil
Nearly anything can be grown in a soilless system by somebody with enough equipment. The useful question is whether it is worth it, in which technique, and what goes wrong.
It can be made to grow, but a soilless system is the wrong tool — usually because of rooting volume, running cost, or a result no better than a pot of compost.
source
GrowingHQ editorial positionmoderate confidence
Carrots need a deep, loose, uniform rooting medium to produce a straight root, which is exactly what channel and water-culture systems cannot provide. A medium bed deep enough to grow a decent carrot is a container of compost with pumps attached.
- GrowingHQ editorial synthesis — GrowingHQ
Checked 2026-08-13
Not that it cannot be done — that there is no reason to. A deep container of compost produces better carrots for a fraction of the equipment.
Techniques that suit it
- Drip-fed mediumSolution is dripped into an inert medium around each plant. The most forgiving technique and the one that suits large, long-season, heavy crops.
Horticultural consensusDepends on conditionsmoderate confidence
Applies when: The only technique that could work, and it offers nothing over a deep pot.
No external citation — see the evidence type above.
Checked 2026-08-13
- Root space
- 30 cm or more of uniform depth. This is the disqualifier: the equipment cost rises steeply with medium depth and the result is no better than soil.
- pH band
- 5.5–6.5
Where these figures come from
- Root spaceSourced guidancehigh confidence
- Royal Horticultural Society: Carrots in containers
Checked 2026-08-13
- pH bandSourced guidancehigh confidence
Outside roughly this band, individual nutrients become unavailable even when they are present in the solution — which is why a crop can starve in a full reservoir.
- Purdue Extension — Purdue University: Hydroponic solution management — pH
Checked 2026-08-13
No nutrient recipes here
GrowingHQ records pH bands, which are measurable properties of nutrient availability, and deliberately records no EC or PPM targets and no mixing instructions. Published targets vary by cultivar, growth stage, water source and technique, and the figures that apply to your system are on the product you bought.
Harvesting
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Carrots — timing
Checked 2026-08-13
- When it is readyLift when the shoulders showing at soil level are the size you want. There is no need to wait for a fixed date — carrots are usable from finger size onwards.
- How to pick itLoosen with a fork before pulling on heavy soil, or the tops snap off and leave the root behind.
- Keeping itMaincrops store for months in boxes of just-damp sand in a cool frost-free place, or can be left in the ground in mild areas under straw and lifted as needed.
Where the harvest guidance comes from
- When it is readyHorticultural consensusmoderate confidence
- Royal Horticultural Society: Carrots — harvesting
Checked 2026-08-13
- How to pick itHorticultural consensusmoderate confidence
No external citation — see the evidence type above.
Checked 2026-08-13
- Keeping itSourced guidancehigh confidence
- Royal Horticultural Society: Storing root vegetables
Checked 2026-08-13
What goes wrong
| Problem | How often | Notes |
|---|---|---|
| Carrot fly | commonsourceSourced guidancehigh confidence
Checked 2026-08-13 | The defining pest of the crop, and almost entirely preventable. |
| Slugs and snails | occasionalsourceHorticultural consensusmoderate confidence No external citation — see the evidence type above. Checked 2026-08-13 | On seedlings, and on roots in wet ground. |
What to look for
Views that settle something a description cannot. Where the photograph has not been taken yet, the description of what it will show is here instead — which is the useful half of it either way.
Described view
A forked and stubbed carrot root beside a straight one, showing the effect of stony or freshly manured soil
Grown with, grown after, grown instead
Every relationship states its mechanism. A pairing nobody can explain is a pairing nobody has checked, and it does not go in.
- Shares a problem withParsleyBoth are Apiaceae and both are hosts of carrot fly, so a parsley bed next to a carrot bed maintains the pest between carrot crops and undermines the rotation.
source
Sourced guidancehigh confidence
- Royal Horticultural Society: Carrot fly — host plants
Checked 2026-08-13
- Grown togetherOnionInterplanting alliums with carrots is a long-standing practice on the basis that onion scent masks carrot scent and confuses carrot fly. Trial evidence is mixed, and the effect — where found — requires far more onion than carrot to be worth anything.
Sourced guidanceSources disagreelow confidence
Sources disagree: Some trials report a measurable reduction in carrot fly damage under heavy interplanting; others find no effect at practical planting ratios. A mesh cover produces a reliable result where this does not.
- Royal Horticultural Society: Companion planting
Checked 2026-08-13
Recorded because it is one of the most repeated pieces of companion-planting advice, and a grower deserves to know how thin the evidence is.
Safety and edibility
- Which parts are edibleCarrot foliage is edible in small quantities and is used as a herb, but it contains furanocoumarins that can cause skin sensitivity to sunlight in some people after handling.
source
Horticultural consensusmoderate confidence
- Royal Horticultural Society: Plants that may cause skin reactions
Checked 2026-08-13
Wear long sleeves when clearing large amounts of carrot foliage in bright sun if you know you react to it.
Sources for this page
Agriculture and Horticulture Development Board · GrowingHQ editorial synthesis · Home and Garden Information Center · OSU Extension Service · Purdue Extension · Royal Horticultural Society · University of Minnesota Extension · USU Extension
Each figure on this page carries its own citation, under the “where these figures come from” note in its section. Record last reviewed 2026-08-13.