Causes of and Control Methods for Premature Bolting in Carrots
During the growth of carrots, premature bolting can occur, also known as premature bolting; it refers to the phenomenon in which the fleshy root of the carrot is affected by low temperatures early on and bolts during vegetative growth, resulting in carrots with more fiber that cannot be eaten normally, seriously affecting yield and quality. So what causes premature bolting in carrots? How should it be controlled? Let's take a look at the detailed introduction below.
1. Low temperatures at the seedling stage
During the carrot seedling stage, if it encounters low temperatures below 15 degrees, just over half a month is enough to vernalize it and carry out flower bud differentiation. For spring-sown carrots, because the early temperatures are relatively low, the mid-period temperatures are high, and the sunshine duration is long, bolting is very likely to occur. The higher the sowing, the longer the seedlings are exposed to low temperatures, and the higher the bolting rate; the opposite is also true.
Control method: When sowing carrots in spring, choose a suitable sowing time, try to avoid low temperatures during the seedling stage, and sow when the temperature is stable. If the seedling stage encounters low-temperature weather, take good insulation measures to reduce the bolting rate.
2. Variety reasons
In addition to environmental factors, carrot bolting is also related to its own genetics. Some varieties have a relatively high natural bolting rate. In addition, old seeds with low vigor will also produce weak seedlings, and the bolting rate will also rise later.
Control method: When planting, choose varieties with strong winter hardiness and late bolting, and use new seeds. Sow at the appropriate time according to local climatic conditions; sowing too early or too late is not suitable.
3. Improper cultivation
The soil fertility status and an improper ratio of nitrogen, phosphorus, and potassium during fertilization will all affect the carrot's growth and development, indirectly leading to flower bud differentiation and causing premature bolting.
Control method: Strengthen fertilizer and water management, choose soil with a deep, loose, and fertile layer for planting, base fertilization mainly on organic fertilizer, use nitrogen and potassium fertilizers as the main chemical fertilizers, and apply less phosphorus fertilizer to reduce the bolting rate.
4. Growth regulator reasons
During carrot growth, in order to promote its growth and improve yield and quality, many farmers spray growth regulators, but carrots are relatively sensitive to acetic acid substances, which will promote their growth, so caution is needed when using them.
Control method: Be cautious when using growth regulators, spraying acetic acid substances, or when carrots show early bolting. Growth regulators that inhibit bolting can be sprayed, such as 0.1%-0.5% maleic hydrazide growth regulator substances, which can delay the bolting time of carrots.
The above is an introduction to the causes of and control methods for premature bolting in carrots. We hope it can help you. If you want to learn more related knowledge, please stay tuned to us.