How to grow carrots on the allotment

With its distinctively coloured root and attractive frond-like foliage the carrot is almost a symbol of the British allotment. Its origins however are thought to be in south-western Asia and its natural colour purple. Nowadays orange varieties are most common but carrots are available in purple, yellow, red and white too. Try a packet of rainbow mix for some of each colour.

Carrots come in different shapes and sizes from small round varieties like Rondo, short, stumpy Chantenay, cylindrical rooted Nantes and the classic long, conical Autumn King.

Early and late cropping carrots are available for a long season.

Carrots are reasonably easy to grow and can be sown from February until July. They need warm soil to germinate so early sowings will need to be covered by a cloche otherwise germination rates will be very poor. They do not transplant well so sow direct into the soil. Avoid digging manure into the soil as this causes the roots to fork making them difficult to prepare for cooking.

It is often said that carrots need deeply cultivated, light, sandy soil but I have grown them successfully on my heavy clay no-dig beds for years. The snag is that clay soil takes longer to warm up so it can be difficult to get them started, and once started in warmer top soil their growth can be stunted when they reach the colder clay below. Hence later sowings will usually be more successful, particularly if the spring is a cool one.

You will never buy a carrot from a supermarket that tastes anything like those you have sown, grown, pulled from the ground and cooked the same day.

Sow carrot seeds

Make a drill about 10 - 15mm deep in the soil and water before sowing. Sow seeds sparingly so that thinning them out later is not needed as this can attract carrot fly. Cover the seeds and then firm them down. Some people advise walking down the row to do this but that seems too harsh to me so I press down on the soil with my hand. The purpose of this is to ensure that the tiny seeds make good contact with the soil and whilst some consider this an old wives tale I have had noticeably better germination rates since I started to do it.

Unless the weather is exceptionally warm and dry the seeds should not need watering again until they start to germinate, which should be in about 10 - 14 days.

Sow successionally every two weeks or so for a continuous crop. Rows should be about 20 - 30cms apart depending on variety.

Carrots do not transplant well so starting them in pots or modules is not benificial.

Grow carrots

Once they are growing carrots need little maintenance other than regular weeding. They are fairly drought resistant and will send their roots down to search for water so you will only need to water them in long, dry spells. When it is necessary, water thoroughly and occasionally so that the water soaks well into the soil.

Harvest carrots

Dependant on variety, carrots take about 10 - 16 weeks to mature. Harvest when the soil is damp to avoid snapping the roots. Use a trowel or hand fork to loosen if necessary. Firm in any disturbed roots that you don’t need and water to settle.

Carrots, in particular late varieties like Autumn King, will happily stand in the ground until December or even beyond and I find this is the best way to store them. They can also be kept in damp sand or in the freezer.

Carrot problems

Carrot fly is the main problem you are likely to encounter. The larvae of the fly damage the root causing unsightly scarring. Often the damage can be removed by peeling or scrapping and the carrots remain perfectly edible.

Covering with fleece or a very fine mesh net will reduce the risk of carrot fly damage as will sowing resistant varieties such as Flyaway and Resistafly.

Carrot fly is attracted to the smell of carrots which is released when disturbing the foliage so remember to sow sparsely so that thinning out is not necessary.