How to Grow Carrots
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Carrots develop normally within a great range of temperatures and are grown throughout the world with the exception of the very warmest areas.
Root growth is fastest at a temperature between 15 ºC( 59 F) and 18 ºC(64.4 F), while optimum temperatures for shoot growth are somewhat higher. Seeds of carrot may germinate at low temperatures but the germination period is shorter at higher temperatures and a soil temperature of at least 10 ºC( 50 F) is therefore recommended. Carrots are tolerant of long days but need low temperatures to induce flowering.
Carrots are fairly fussy growers. They love light, stone free, well drained, fertile soils with plenty of well rotted organic matter in them. Rich sandy peaty soils are perfect in providing the best conditions for the carrot roots to penetrate deeply and to swell.
The pH value should 6.5 to 7.5 for best results. Potassium promotes solid, sweet carrots. Wood ashes contain soluble potassium, which reaches the plant quickly. Excess Nitrogen causes branching and hairy, fibrous roots.
It is much harder to grow good carrots in heavy clay soils or soils which are compacted or stony. Such conditions can cause the forking of roots. Water logged sites are also less than ideal. If you have a heavy soil, dig in plenty of manure several months before planting. Never work fresh manure into the soil as this encourages sappy growth and forking of roots. Add leaf mold to lighten heavy soil and rake in Nitrogen fertilizer before sowing a crop in poor soil.
Early carrots appreciate a sheltered position but main crop need an open sunny site. If you plant under a tree, ensure at least 6 hours of sun per day.
Carrots should be rotated around the garden to avoid the build up of diseases. It is recommended that you grow them in a different bed each year over at least a three year cycle.
Soil temperature can be critical for successful carrots. At temperatures below 5 ºC(41 F) they will struggle to germinate. Slightly higher temperatures and they could take up to 35 days to start. If you wait until the soil is 10 ºC(50F) germination will occur within ten days. Basically if the soil is chilly to touch do not plant.
Curiously even within a variety a carrot’s colour and shape can vary according to the type of soil and commencement temperature. Lower temperatures give yellower carrots and reduced size and shape.
Proper watering can make a difference. Carrots need 2cm of water from rainfall each week during the growing season. Soaking well when watering helps to promote good root development. The domesticated honeybee may get more glory, but when it comes to pollinating carrots, one tiny alfalfa leafcutter bee can do the job of 20 of its larger, noisier, more irritable cousins, says a U.S. Department of Agriculture researcher. Click here for more details.
Not all of the chemical constituents of carrots are for our health; some appear to be there for the health of the carrot itself. One reason that the carrot can be stored for long periods of time, such as over winter in a root cellar, is that the carrot has a mechanism to guard against microbial decomposition (rot).
There are three enemies of carrot storage: wilt, re-growth and rot. The first of these is no problem if the carrot is stored where the humidity is high. The second is of little consequence if the carrot is stored at 0 to 5°C.(41F)
The carrot itself contributes much toward conquering the last enemy, rot. At the present time, scientists are busy determining how the disease response mechanism of the carrot operates. There appear to be three lines of resistance which the carrot uses, based on the chemicals contained within the carrot and its skin. Read more at www.thecarrotmuseum.co.uk. How do Carrots produce seeds? HERE
Seed Sowing Methods
Carrots are normally grown straight in the ground and then thinned in stages to obtain the correct distance apart. Never plant in cold or weedy soil as carrots are difficult to weed once established.
Carrots are cool-weather vegetables, so start sowing about two weeks before the last expected frost in your area.
Make successive plantings every three weeks but avoid the hottest part of the summer.
Sow in drills about 2cm(.8inch) deep and 15cm(5.9inches) apart. With this spacing the foliage of adjacent plants will make a dense canopy when the plants are mature.
Place a 1cm(.4inch) layer of peat moss in the bottom of each furrow,
Sow the seeds sparingly on top, then cover with about 0.5cm(.2inch) of soil. Seeds must be kept moist to germinate. Mulching with straw/grass will help hold the moisture, and will also make it easier to water without disturbing the seeds.
When sowing seeds, try to space them 1cm(.4inch) apart. The tiny seeds make spacing difficult, but it will be easier to thin without disturbing the plants you plan to leave, if there is a little space between them. Seeds can be mixed with sand to make sowing a little easier.
You can try mixing radish seeds with the carrot seeds. The carrot seeds are slow to germinate, and the radishes, which germinate and grow very quickly, will mark the row until the carrots come up.
A second crop of carrots can be planted in late summer or early autumn in most areas. If a hard frost threatens, protect your fall crop with a heavy mulch.