Root
How to grow carrots
Daucus carota subsp. sativus
Sow carrots thinly where they are to grow, from March under fleece to early July, in light, stone-free soil that was manured for the previous crop and not this one. Cover the row with fine insect mesh from the day you sow to keep carrot fly out, thin in the evening, and water evenly so the roots do not split. Fresh manure and rich feeding give forked, hairy roots. So place carrots in your crop rotation after peas, beans or brassicas, on ground that was fed the year before.
- Hardiness
- Hardy, maincrops stand in the ground into winter
- Position
- Full sun
- Soil
- Light, sandy, stone-free; never freshly manured
- Ideal pH
- 6.5 to 7.0
- Water
- Low to moderate, keep even to stop splitting
- Feeding
- Light feeder
Sowing and planting carrots
WhenSow Mar to Jul direct in succession; harvest Jun to Nov
Starting off
Always direct; germination takes 14 to 21 days and needs soil above 7 °C, so sow early types under fleece from March and maincrops from mid April to early July. Mix the fine seed with sand to sow thinly, water the drill before sowing in dry weather and keep the surface moist until seedlings show.
Spacing and planting
Sow 1 cm deep in drills 15 cm apart for early types, 30 cm for maincrops; thin to 5 to 8 cm, or leave finger carrots at 2 to 3 cm.
Varieties worth growing
- Early Nantes 2
- Early cylindrical carrot for March sowings under fleece and for successional sowing all summer.
- Amsterdam Forcing 3
- The earliest, small and sweet, for cloches and pots in February and March.
- Autumn King 2
- Big maincrop that stands in the ground into winter and stores in sand.
- Flyaway F1
- Partial resistance to carrot fly, worth it where you cannot cover the row.
- Parmex
- Round, golf-ball carrot that grows in 15 cm of soil: shallow beds, heavy clay and pots.
Carrots month by month
Timings are for central England. Allow two weeks later in the north and on cold, heavy soil.
- January
Nothing. Last of the stored roots.
- February
Sow Amsterdam Forcing under a cloche on light soil in the south.
- March
Sow Early Nantes under fleece once soil is above 7 °C. Mesh goes on at sowing.
- April
Sow every three weeks for succession. Thin to 5 cm in the evening.
- May
Sow maincrops after mid May to miss the first carrot fly generation.
- June
Lift early sowings as finger carrots. Keep sowing Nantes types.
- July
Last sowing for autumn. Water evenly in drought to stop splitting.
- August
Lift as needed. Watch for second-generation carrot fly from late August.
- September
Lift maincrops on light soil before the autumn rains; leave on heavy soil.
- October
Lift and store in damp sand in a cool shed, or cover the row with straw.
- November
Pull from under straw as needed.
- December
As November. Order seed.
Feeding carrots
A light feeder that forks and goes hairy on fresh nitrogen. Feed the crop before it, not the carrot. On poor soil, the best fertiliser for carrots is a light dressing low in nitrogen, with a little potassium for root development.
Grow lean. Fresh nitrogen or manure causes forking and hairy, mis-shapen roots, a little potassium suits root development, but otherwise feed sparingly.
Feeding plan
The previous autumn
Garden compost
Dig in for the crop before carrots; nothing fresh in the carrot year.
Sowing, poor soil only
Fruit & Vegetable Fertiliser 4-5-6
70 g/m² (the lower end of the label) raked in a week before sowing. On good soil, none.
Monthly through growth
1 g per litre as a foliar spray; supplies the trace elements without nitrogen.
Sowing, only where last year's roots cracked
1 to 2 g/m² (a quarter to half a level teaspoon), scattered evenly and never exceeded.
Signs to watch
Forked, hairy or split roots
Fresh manure or stony soil, not a feeding fault
Grow on ground manured a year earlier
Cracking on light soils with a dull core
Boron short
Seaweed or a dilute borax application next season
Lush ferny tops and thin roots
Excess nitrogen
No further feeding, potash only
Pests, diseases and problems
Leaves reddish and wilting, roots tunnelled just under the skin with rusty brown mines
Carrot fly larvae; the fly is drawn to the smell of bruised foliage
Cover the row with fine insect mesh from sowing, or a 60 cm high barrier; thin in the evening and firm the soil back; sow after mid May to miss the first generation and lift before the second in late August; grow Flyaway.
Seedlings disappear in the first fortnight
Slugs
Sow a little thicker, torch patrols, nematodes in April on wet soil.
Leaves yellow and twisted, plants stunted, roots reddish
Carrot motley dwarf virus spread by willow-carrot aphid
Mesh over the row stops the aphid too; pull affected plants.
Roots split lengthways
Heavy rain or watering after a dry spell
Water little and often; lift maincrops before autumn rain on light soil.
Green shoulders on the roots
Light reaching the top of the root
Draw soil up over the shoulders when thinning.
Roots forked and hairy
Fresh manure, stones, or compacted soil
Grow on ground manured for the previous crop; on stony ground grow Parmex or use a raised bed of sieved soil.
Harvest and rotation
Harvest and storage
Earlies are ready 10 to 12 weeks from sowing when the shoulders are 1 to 2 cm across; maincrops at 14 to 16 weeks. Expect 3 to 4 kg per 3 m row. Store maincrops in damp sand in a cool shed, or leave in the ground under straw until February.
Rotation and companions
Rotation: umbellifer (carrot) family with parsnip, celery and parsley, 3-year gap; follows peas, beans or brassicas well.
Good to knowSow direct (they dislike transplanting); thin in the evening and firm soil back to reduce carrot-fly attack, or use a fleece barrier.
Growing carrots in pots
A pot or trough at least 30 cm deep grows Nantes types; 15 cm is enough for Parmex. Fill with sieved multipurpose and a quarter sharp sand, no added fertiliser beyond a pinch of the 4-5-6, and sow thinly on the surface, cover 1 cm and keep moist until seedlings show. Pots on a table or wall are above carrot fly height and rarely attacked. Water evenly; a pot that dries then floods gives split roots.
Carrots: common questions
Why are my carrots forked?
Fresh manure or fertiliser in the carrot bed, stones, or compacted soil: the root hits something it does not like and splits. Grow on ground manured for the previous crop, and on stony or heavy soil grow a round variety or a raised bed of sieved soil.
How do I stop carrot fly?
Cover the row with fine insect mesh from sowing to lifting. Nothing else is as reliable. Thinning in the evening and firming the soil back helps, as does sowing after mid May, and Flyaway has partial resistance.
Can I leave carrots in the ground over winter?
Yes on free-draining soil: cover the row with 15 cm of straw and pull as needed until February. On heavy wet soil lift in October and store in boxes of damp sand in a cool shed.
Sources
Growing information on this page was checked against these references in November 2026. Feeding rates are Dr Forest label rates.