In the 24 solar terms of the valley rain solar term, many farmers began to prepare to plant sweet potatoes in the spring, but some people sow seedlings and plant, and some buy sweet potato seedlings and plant seedlings. Taking advantage of the opportunity to plant sweet potatoes before and after the rain, today the agricultural technology basket will give you a special talk - when planting sweet potatoes in spring, how to correctly use potato tubers to propagate and cultivate high-quality sweet potato seedlings with all seedlings and uniform and robust, so as to help everyone grow more high-yield and high-quality sweet potatoes.
1. Time and temperature requirements for sweet potato sowing and seedling
Generally speaking, when planting sweet potatoes in spring, it is better to sow seedlings with potato tubers first, and transplant seedlings after waiting for the tubers to grow seedlings. The commonly used potato seed seedling breeding methods for planting sweet potatoes mainly include hotbed (seedbed) seedlings, film seedlings, and open-field seedlings (everyone can choose flexibly according to their own planting conditions), but generally sweet potatoes that take hotbed (seedbed) seedlings can often obtain better growth and higher yield in the later stage.
(1) Under normal circumstances, if it is a sweet potato that is sown first and then transplanted, it is generally necessary to use potato tubers to sow seedlings and raise seedlings 1-2 months before transplanting (before planting). As for the specific time of sweet potato sowing and seedling, it is different due to the difference in spring temperature between the north and south regions, and different due to the open field seedling raising and arch shed seedling, and the sweet potato sowing and seedling raising time is subject to the actual temperature conditions.
(2) In general, because sweet potato is a type of crop that likes temperature and heat, its growth and development has higher requirements for temperature, generally in the middle of February - mid-April every year or in the rain-stinging solar term to Qingming-Guyu to start sowing potato seedlings is more appropriate, the average temperature of day and night when sowing potato tubers is required to reach about 15-20 degrees, because under the warm and humid soil environmental conditions of not less than 15 degrees, we can quickly germinate young shoots and grow seedlings in the soil of potato seeds.
For example, in the southern region where the temperature rises early in spring and the greenhouse/arch shed with a better thermal insulation environment, the sowing and raising of sweet potatoes can generally start from mid to late February to mid to early March, while the northern areas with late spring temperature and direct open field sowing and seedlings may need to wait until the soil temperature reaches 15 degrees or more in April before the sowing and raising of sweet potatoes can be carried out.
(3) For the time of sweet potato planting, the agricultural technology small back basket recommends that you remember a sentence: sweet potatoes generally start to sow seedlings about 30-45 days before planting, when the temperature does not reach 15 degrees, do not sow potato seeds, do not transplant sweet potato seedlings, and wait until the temperature reaches more than 15 degrees (especially for sowing sweet potato seedlings in the open field), we will sow sweet potatoes or transplant sweet potato seedlings. Generally, the need for open-field seedlings is delayed by about 2 weeks compared with the time of seedbed (hotbed) seedlings, and the need for seedlings with only mulch film is generally delayed by about 1 week than the time of seedbed (hotbed) seedlings.
Second, the selection requirements of sweet potato sowing seedling land and seedbed soil
Only with suitable soil conditions for seedling raising can high-quality sweet potato seedlings with strong sprouts and seedlings be cultivated. When you choose the seedbed soil used for sowing sweet potato seedlings, the agricultural technology basket recommends that you focus on remembering the following requirements:
(1) The seedbed for sowing and raising seedlings must be able to receive sufficient sunlight.
(2) The seedbed for sowing and raising seedlings can be flat or slightly higher plots, but it must not be low-lying land that is prone to water accumulation and waterlogging and poor drainage.
(3) The seedbed for sowing and raising seedlings can be loose sandy soil or ordinary loam soil with good permeability and air permeability, but it must not be clay soil with heavy soil and easy to harden, nor can it use the land that has just been planted with sweet potatoes in the last 2-3 years as a seedbed to sow sweet potato seedlings.
(4) After we choose the sweet potato seedling planting land, first sprinkle some well-rotted farmhouse manure or high-quality organic fertilizer, and then deep rake and make a furrow to prepare the seedling bed (about 1.3-1.5 meters wide, about 20-30 cm deep, and the bottom of the seedling bed is recommended to be dug into the shape of a turtle's back), and finally sprinkle a layer of two or three centimeters thick fine sand on the furrow surface to prepare for sowing potato seeds. Sprinkle a layer of fine sand, and everyone can do it in the land preparation to improve the germination rate and seedling quality of potato seeds after sowing.
3. Selection standards and processing requirements for sweet potato sowing and seedling
As the saying goes, "good seedlings make good seedlings". Therefore, if you want to cultivate high-quality and robust sweet potato seedlings, then you must strictly grasp the selection of potato seeds, and the agricultural technology small back basket recommends that you select the best quality potato seeds for sowing seedlings according to the following criteria:
(1) Try to choose potato seeds that are treated with detoxification.
(2) Select potato seeds with good skin gloss, full and full potato pieces, more bud eyes on potato tuber buds, complete and no wounds / no disease spots / no insect eyes / and have not suffered from flooding, frost, and serious pests and diseases before last year's harvest, the size of potato seeds is generally 150-250 grams (a single potato seed is about 3-5 taels), and the large potato seeds should be cut into small potato pieces, and the potato pieces should be cut into small potato pieces, and each small potato piece that was cut off can have 1-2 full bud eyes.
(3) Do not use sweet potato pieces that are excessively dehydrated and wilted, soft and black in potato pieces, shriveled and chaff in potato pieces, and have dents/lesions/insect holes/cracks on the surface of potato pieces to make potato seeds.
(4) After selecting the potato pieces used for sowing seedlings, the small back basket of agricultural technology suggests that you should properly treat the potato seeds according to the following methods before sowing (disinfection and sterilization treatment to avoid diseases during the seedling stage) (1) Stir and blanch the seeds continuously with warm water at about 50 degrees for 10-15 minutes; (2) Put the potato seeds in the water such as carbendazim solution or methyl tobuzin solution or methyl thiophanate, etc., and soak the seeds continuously for about 5-10 minutes.
The concentration of soaking liquid medicine: 50% carbendazim diluted with water 500-800 times, 50% methyl tobuzin diluted with water 300-500 times, 50% thiophanate-methyl diluted with water 800-1000 times after soaking, and then soaked, and after the potato seeds are soaked and disinfected, they can be sown and used after being dried by natural wind.
If you do not use fungicide solution to soak the seeds when raising seedlings, you can also spray all the potato seeds evenly with the fungicide solution after they are placed on the seedbed (completely wet).
Fourth, according to the size of the sweet potato planting area, reasonably calculate the amount of potato tuber used and the required seedbed area
This is relatively simple, you just need to remember the following method of calculating the amount of potato seeds required to plant sweet potatoes: under normal circumstances, when sowing sweet potatoes in spring and raising seedlings, it generally takes about 60-80 kg of potato seeds for each acre of sweet potato seedlings, and about 20-23 kg of potato seeds can be placed per square meter of seedbed soil.
Before planting sweet potatoes, the agricultural technology basket suggests that you calculate how much seedbed land you need to prepare and how many kilograms of potato seeds you need to prepare according to the above two sets of numbers.
5. Potato seed seedbed sowing method and potato seed placement technical requirements
(1) Before the pre-processed potato seeds are transferred to the seedbed for sowing, and then according to the row spacing of about 13-15 cm between each potato block (so that the seeds can cultivate better strong seedlings, and the potato seeds are discharged too tightly to grow strong and good seedlings), all the sweet potato seeds are discharged into the seedbed in accordance with the method of "dense row of large potato seeds, sparse row of small potato seeds", "deep row of large potato seeds, shallow row of small potato seeds", and discharge of potato seeds can be flat or straight. It is also possible to arrange diagonally (diagonal row is recommended, with the head of the potato seed up and the bottom down).
(2) After all the potato seed beans are placed on the seedbed, then sprinkle a layer of fine sand about 2-3 cm thick on the potato seeds (as long as the potato seeds are exposed at the thinnest part of the soil, and the last part of the soil should not exceed 5 cm), when raising seedlings in the open field, if the temperature is too low, the agricultural technology small back basket is recommended to cover the plastic film or build a small arch shed, and finally use small water to spray the entire seedbed soil to soak it (the seedbed covered with plastic film should be covered with plastic film in time after watering simple wind drying).
(3) After the potato seeds are sown in the seedbed, if the temperature can reach about 20 degrees and keep the seedbed soil moist, it generally only takes about 7-10 days for the potato seeds to germinate and emerge, and it only takes more than 1 month or so to grow to the sweet potato seedlings suitable for transplanting (the seedling height grows to about 20-25 cm), and the seedling height of the sweet potato seedlings when transplanting and transplanting seedlings cannot be less than 10 cm.
6. Technical requirements for the management of sweet potato seedlings after sowing
There are two technical points in the seedling management of sweet potato seedbed sowing and rapid cultivation of strong seedlings: one is the early high temperature germination + mid-term constant temperature seedling promotion + low temperature seedling refining in the later stage, one is to first heat up and promote the growth and then cool the seedlings, mainly to heat up and promote growth, supplemented by low-temperature seedling refining, one is to promote the seedlings before the potato seeds emerge from the seedlings, and the seedlings are mainly refined after the seedlings emerge.
(1) Raise the temperature to promote seedlings. For the sweet potatoes sown in the greenhouse (with the conditions of heating and heat preservation), the agricultural technology small back basket recommends that you put the potato seeds in the warm and humid conditions of 25-30 degrees before sowing for a week, and wait for the sweet potato germination eye, and then put the potato pieces on the seedbed for sowing, and raise the temperature of the seedbed to about 32-33 degrees in the first 3-4 days after sowing (more than 35 degrees to ventilate and cool), so that the sweet potatoes can germinate faster.
(2) Cooling seedlings. When all the potato seeds we sown in the seedbed are all seedlings, at this time, we need to gradually reduce the temperature of the seedbed to about 28-30 degrees through daytime ventilation, and then gradually reduce the temperature of the seedbed to about 25 degrees after 5-7 days; Gradually reduce the temperature of the seedbed, increase the length of sunshine time day by day (the minimum temperature of the seedbed cannot be lower than 20 degrees, and when it is 20 degrees, the sweet potato seedlings can be fully ventilated and sunburned during the day, and the cover can be lifted early and evening), until all the mulch on the seedling bed is completely lifted 1-2 days before the sweet potato seedlings are planted (when the seedlings are more than 10 cm high, as long as the temperature reaches 20 degrees, they can be ventilated day and night), so that the sweet potato seedlings can fully adapt to the temperature and humidity environment and natural climate conditions of open field planting.
(3) Fertilizer and water seedlings. After the sown potato seeds are all germinated and full seedlings, the whole seedling period should be flexibly watered to keep about 70% of the soil of the seedbed moist and not drought, this stage can not be too wet and waterlogged, and the seedbed can not have water, the general seedling period of the seedbed soil ground does not change dry and white, do not water, wait until the seedbed topsoil is white, a small amount of watering to keep the seedbed moist; If the sweet potato seedlings grow too fast and too vigorous at this time, and the stems are thin and weak, you can spray potassium dihydrogen phosphate with a small amount of urea water at this time.
Later, when the sweet potato seedlings grow to about 20-30 cm tall or have 4-8 leaves, we can prepare to harvest the sweet potato seedlings and plant them in the field.
The above is the agricultural technology knowledge of spring sweet potato sowing and seedling raising introduced to you by the agricultural technology basket today, have you learned it?
The headline number of this article is original and first published, without unauthorized permission, no one is allowed to move, copy, plagiarize, violators must be investigated