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how to grow garlic guide

How to grow carrots

Carrots are an easy and rewarding crop to grow, great for encouraging children to eat their vegetables! With so many varieties of this popular vegetable available, carrots can be grown in beds, containers and even window boxes making them suitable for gardens of any size. The taste of a home-grown carrot is far superior to supermarket produce - try growing your own carrots and see for yourself!

When to grow carrots

Carrots are normally sown outdoors between March and July and harvested throughout the summer and autumn. Early varieties such as ‘Nantes 2’ can be sown as early as February under cloches or in greenhouse borders. Growing carrots under cloches helps warm the soil and speeds up germination, which is particularly useful if you live in cold regions or want to make an early start.

Carrot varieties


Early carrots (good for containers) Maincrop carrots Chantenay carrots (good for containers) Colourful carrots
Nantes 2 Kingston Caracas Purple Haze
Mignon Autumn King 2 Carson Yellowstone
Mini Finger Bangor Supreme Chantenay Red Cored Rainbow
Parmex Sweet Candle Royal Chantenay Healthmaster
Tendersnax White Satin
Mokum

Where to grow carrots

Carrots grow best in light, fertile soil in a sunny position. Heavy or stony soils can cause stunted or forked carrots. If you have clay soil , try growing varieties such as ‘Parmex’ and ‘Carson’, which have short roots, or alternatively grow your carrots in containers (see below for more information about how to grow carrots in containers). For the best crops add plenty of organic matter to your soil before growing. Carrots dislike freshly manured soil so seed beds are best prepared in the autumn before sowing. You can also grow carrots in a greenhouse throughout the winter for a spring crop. Carrots are unsuitable for growing in a greenhouse during the spring and summer months as they prefer cool conditions.

how to thin carrots

How to sow carrots

Before sowing carrots, remove any weeds and dig your soil to a fine tilth, breaking up any large lumps. Make drills in the soil with a trowel or by laying an old broom handle or bamboo cane across the ground and gently pushing down. Aim for a depth of 1cm (½in), leaving about 30cm (12in) between each drill. Sprinkle your carrot seed thinly along the drill - sowing too thickly will make the seedlings difficult to thin out later on! Gently draw soil from the edges of the drill back over your seeds so they are well covered. Water the area well with a fine-rose watering can to minimise seed disturbance. Keep the soil moist until germination, which should take about 10-20 days.

Thinning carrots

Once your carrot seedlings are large enough to handle they will need thinning out to allow each carrot room to grow properly. This is best done in stages so that you have spare seedlings should slugs attack! For the first thinning aim to leave one seedling every 2-4cm, pulling out any in-between. About four weeks later you can further thin your carrots to a final spacing of 10cm (4in) - the thinnings taste delicious in salads. If you’re growing finger or baby carrots then a final spacing of 5cm will be sufficient.

Caring for your carrots

Watering should be kept to a minimum once seedlings have emerged - only water when the soil is dry. Make sure your carrot plants are kept weed-free to reduce competition for light, nutrients and water. If the shoulders of your carrots poke through the soil then they can be earthed up slightly to prevent them turning green.

Growing carrots in containers

Carrots are just as happy growing in containers as they are in the ground - ideal for patios and balconies! It’s best to choose a container at least 20cm (8in) deep to allow the roots to grow. Choose small or early varieties of carrot such as ‘Parmex’, ‘Mini Finger', ‘Mokum’ or Chantenay types such as ‘Supreme Chantenay Red Cored’. Any compost can be used when growing carrots on the patio, including multi-purpose and soil-based composts (John Innes). You’ll need to feed your carrots throughout the season to ensure good growth - a balanced liquid feed can be used every two weeks or alternatively use a slow-release fertiliser. Make sure the compost doesn’t dry out, especially during hot weather. It is possible to try growing carrots indoors but this is not normally recommended. Carrots are a cool season crop, preferring low outdoor temperatures and high natural light levels in order to flourish.

Harvest

Early varieties such as ‘Nantes 2’ can be harvested from 9 weeks after sowing and maincrop varieties such as ‘Autumn King 2’ can be harvested from 11 weeks. These times may vary according to the growing conditions so it’s worth pulling a few ‘test’ carrots to see how they’re doing! Carrots can be stored for up to four months if placed in boxes of slightly damp sand and kept in a cool, dry and frost-free place. Maincrop varieties such as ‘Bangor’ are better for storing than small early varieties.

Carrot fly

carrot fly

Unfortunately carrot fly are a common pest which can quickly spoil your crop. The larvae of these flies burrow into the carrots leaving brown tunnels as they go. If badly infested, the carrots can become susceptible to rots and are often inedible. Some chemical sprays are effective against the adult fly, but there are no chemicals approved for use by the amateur gardener against the damaging larval stage. However, there are a few cultural practices that can help:

  • Use resistant varieties of carrot such as ‘Flyaway’ or ‘Resistafly’. For the best results grow these alongside non-resistant varieties - the carrot fly will be attracted to the non-resistant varieties, leaving the resistant varieties clean
  • Sow seed very thinly to prevent the need for thinning out at a later stage. Female carrot flies are attracted by the smell of freshly pulled carrots and crushed foliage.
  • Thin your carrots in the evening when the flies are less active. Dispose of the thinnings quickly to prevent the carrot scent lingering.
  • Surround crops with a barrier at least 60cm high, using fleece or clear plastic sheeting. Carrot fly are reportedly weak fliers and will be unable to penetrate the barrier. Alternatively cover the whole crop with horticultural fleece or Enviromesh, pegging down the edges securely with anchor pegs or similar.
  • Practise crop rotation. Carrot fly can over-winter as pupae in the soil, re-emerging to infect your young crop in the spring.