When can I sow carrot seed in the UK?

Late February under cloches in southern England; mid-March to July outdoors across the UK; first sowing in early April further north. Carrots want soil above 7°C to germinate, so don't push them in too early. Successional sowings every three weeks from April to early July give a steady supply through summer and autumn. Late-July sowings of fast varieties crop into November.

Why are my carrots forked?

Forked roots mean the soil was too stony, too rich, or too compact. Carrots fork around obstructions or split when their growing tip hits stones. Don't add fresh manure or compost to the bed before sowing — high nitrogen makes them branch. For heavy clay, grow short or globe varieties (Parmex, Chantenay) in deep tilth or in containers of loose multi-purpose compost.

How do I stop carrot fly?

Cover the bed with enviromesh or 60-cm-tall fleece from sowing onwards — the fly can't fly higher than that. Thin seedlings in the evening on a still day; the bruised foliage attracts the fly. Sow Resistafly or Flyaway varieties for partial resistance, though no carrot variety is fully resistant. Companion planting with chives, leeks or onions confuses the fly but only modestly — netting is the only reliable defence.

How do I know when carrots are ready?

Push back the foliage with your fingers and look at the shoulder of the root. Early varieties are ready when 1–2 cm across, usually 10–12 weeks from sowing. Main-crops are ready from August onwards when 3–5 cm across. Don't wait too long — over-large carrots get woody and coarse.

Can I grow carrots in containers in the UK?

Yes — short varieties (Parmex, Paris Market) do well in 30 cm pots or window boxes. Use sieved multi-purpose compost. Sow thinly, thin to 3 cm apart, keep consistently watered. Carrot fly affects container-grown carrots less because the bed is usually higher than 60 cm; raise containers on bricks to be safe.

How do I store carrots through winter?

Lift main-crops before the first hard frost. Cut foliage 2 cm above the root (don't twist; you'll wound them). Layer the roots in damp sand in a wooden box, ensuring they don't touch. Store in a frost-free shed or garage. They keep firm until April. Alternatively, leave them in the ground covered with a deep straw mulch — fine in southern England, risky north of the Midlands.

Carrot — Grow

Carrot

Daucus carota subsp. sativus

vegetable☀️ full-sun🪴 sandy loam📏 small🌡️ RHS H5

📋Quick Facts

Height

0.3-0.5m

Spread

0.1-0.2m

Water

💧💧 Average watering

Hardiness

Zone 2-11

About

Sow carrot seed direct from late February under cloches, March to July outdoors — successional sowings every three weeks for a steady crop. Carrots want light, stone-free soil; heavy clay or stony ground gives forked roots. The dominant enemy is carrot fly (Psila rosae), so cover the bed with enviromesh or a 60-cm-tall fleece barrier from sowing onwards — the fly can't fly higher than that. Thin seedlings to 5 cm apart and pull thinnings in the evening on a still day; the carrot scent attracts the fly. Carrots are hardy enough to tolerate light frosts (RHS H4) and main-crop varieties stored properly last all winter. Early varieties crop from late June; main-crops from August onwards.

Top tip

Sow thinly in light, stone-free soil, keep moist while germinating, and harvest roots before they become woody.

Also known as: Carota, Möhre, Zanahoria, Wortel / peen, Carotte, Marchew, Cenoura, Daucus carota subsp. sativus

How to grow carrot

1
Prepare the soil
Fork over a sunny bed; remove stones; rake to a fine tilth. Don't add fresh manure (it splits the roots) or lime. Sandy or sandy-loam soil is ideal — for heavy clay, use a deep raised bed of sieved compost.
2
Sow direct
From late February under cloches; March to July outdoors. Make a 1 cm drill with the corner of a hoe. Sow seed thinly along the drill; cover lightly with soil; tamp down with the back of the rake.
3
Cover for carrot fly
From sowing onwards, drape enviromesh or 60-cm-tall fleece over hoops above the bed. Carrot fly can't fly higher than 60 cm; physically excluding them is the only fully reliable defence.
4
Thin seedlings
When seedlings are 5 cm tall, thin to 5 cm apart. Pull thinnings in the evening on a still day to avoid wafting the carrot scent into the air. Water after thinning to settle the remaining roots.
5
Keep weed-free
Hoe carefully between rows; carrots don't like root disturbance. Mulch with grass clippings or straw once seedlings are established to suppress weeds and hold moisture.
6
Harvest
Pull early varieties from late June; main-crops from August to first frost. Tug gently from the base of the foliage. Smaller is sweeter; over-large carrots get coarse.
7
Store
Lift main-crop carrots before the first hard frost. Cut foliage 2 cm above the root; layer in damp sand in a wooden box; store in a frost-free shed. They keep firm until April.

Common questions

Pest Resilience

2/5 — Somewhat vulnerable

Carrot fly is a major pest; use fleece barriers or companion plant with alliums.

Companion Planting

Grows well with

Chive Garlic Leek Onion

Keep apart from

Dill

Visual Characteristics

🍳

Culinary

Culinary Use

Roasted, soups, salads, stews, cakes, stir-fries, juice, glazed

The carrot year in your garden

Dispatching imaginary bots to check your garden out...

What to do now

How to Propagate

🌰Seed

Easy

Hardiness Zones

H1a (tender)H7 (very hardy)

H1a

H1b

H1c

RHS H5

USDA 6–7 equivalent

Carrot

Carrot

📋Quick Facts

About

How to grow carrot

Common questions

Pest Resilience

Companion Planting

Visual Characteristics

The carrot year in your garden

How to Propagate

Hardiness Zones

Names in Other Languages(7)