Carrot Seed Production
Carrot seed production is easy and cheap. Carrot is tolerant to heat and cool weather, and thus can be cultivated through the year.
Carrot Seed Temperature Requirements
The carrot is a cool weather crop and it is not really intolerant towards the cold of winter and frost. During winter the plant develops more slowly than during the warmer spring and summer months.
The carrot seed is also tolerant towards a good deal of heat and can therefore be cultivated right through the year in South Africa.
Carrot Seed Production Soil Requirements
Carrots seeds do best in a deep, well-drained sandy loam or slightly acid loam soil.
In heavy humus-rich soils carrot seeds tend to have too much growth in the leaves and to form forked roots.
Avoid Brackish soils.
A general recommendation is that 1 000 kg of the fertiliser mix (2:3:4 (24) per hectare) should be worked into the soil before planting.
A top-dressing of 100 to 200 kg limestone ammonium nitrate per hectare is applied about 8 weeks after sowing.
Compost or kraal manure is not recommended.
Carrot seeds are intolerant towards a boron deficiency and in an area where it is known that there is a boron deficiency, boron could be applied with safety, because carrot seeds are tolerant towards an excess of boron in the soil.
Carrot Seed Cultivation methods
Carrot seed is sown directly on the land. The soil should be well-prepared, even and fine.
Flood irrigation before emergence of the carrot seed could cause the soil to crust and this could lead to a poor stand.
A system of crop rotation is important to eliminate problems with diseases.
Carrot seeds fit in very well in a crop rotation system where plants like cabbage, cauliflower, lettuce and tomatoes are grown.
A general recommendation is that carrots should not be planted in the same soil more than once every 3 to 4 years. Weeds should not compete with the carrot seeds.
Carrot Seed Sowing seasons
For seed production the sowing season is between February and March. About 4 kg carrot seed per ha is sown.
Carrot seed are preferably sown in rows instead of broadcasting the carrot seeds, because it makes weed control easier.
During the warm summer month’s extensive losses could occur among seedlings due to wilt.
Carrot Seed Water requirements
The moisture content of the soil influences the form and colour of carrots.
A deficiency in soil humidity results in longer carrots.
Very wet conditions lead to a shorter and thicker carrot with a light colour.
As a general guideline it could be accepted that carrots need about 25 mm water per week.
In warm, dry conditions 50 mm would be necessary.
Carrot Seed Pollination and harvesting
Carrots are cross-pollinated plants and the flowers are visited by a large number of insects.
Honeybees, wasps, different kinds of beetles and butterflies are often seen on the flowers.
When the seed is ready to be harvested and it is produced on a small scale, the ripe seed buds should be cut off and spread on a concrete floor or sheet to dry.
When the plants are well dried, the root end is cut off and the plants fed into a threshing machine.
Carrot Seed is also still tread out with a tractor on a concrete floor.
Afterwards the carrot seed is winnowed out as well as possible before it is supplied to the seed merchant.
A good average seed crop is about 600 to 800 kg/ha.
This will depend on the cultivar.
Cultivars like Cape Market and Chantenay form stronger and lusher plants and they produce more seed than for instance Nantes.
The most significant diseases in carrots are Alternaria blight, bacterial blight and root rot as a result of fungi. Aphids, red spider, eelworm, bollworm on seed buds and whitefly are the most important insect pests.
