The absorption of nutrients during the vegetative growth of celery is high, and the absorption of nitrogen, phosphorus, potassium, magnesium, and calcium in this period accounts for more than 84% of the total absorption. The highest amount of nitrogen was required for celery, followed by calcium and potassium, and phosphorus and magnesium were the least. The celery's requirement for boron is also very large. In the absence of boron or due to drought-induced low temperature absorption, the petiole is prone to transverse cracking, ie, stem cutting disease, which seriously affects the yield and quality.

Under the medium fertility level, the fertilization amount per mu for the whole growth period of celery is 2500-3000 kg (or 350-400 kg organic fertilizer) for farmyards, 13-16 kg of nitrogen fertilizer, 5-6 kg of phosphate fertilizer, and 6-9 kg of potassium fertilizer. , Potassium fertilizer sub-basal fertilizer and three top-dressing fertilizer, fertilization ratio 2:3:3:2, all phosphorus fertilizer as base fertilizer, fertilizer and farmyard fertilizer (or commercial organic fertilizer) mixed application.

On basal fertilizers, the application of farmyard manure is 2500-3000kg or commodity organic fertilizer 350-400kg, urea 4-5kg, diammonium phosphate 11-13kg, and potassium sulfate 4-5kg per mu.

After slow-onset seedlings, fertilizer is applied. Mushi urea 6-8 kg, potassium sulphate 3 ～ 4 kg in vigorous growth stage; Mash urea 8 ～ 11 kg, potassium sulfate 3 ～ 5 kg in strong growth stage; Mushi urea 6 ~ 8 kg, potassium sulfate 3 ~ 4 kg.

Long Range Distance Sensor

With long range distance sensor with digital output, you can measure and monitor distances intergrated to your arduino, raspberry pi etc. The Laser Distance Sensor low cost is a competitive measure sensor, can measure from 3cm to 40m, 100m, max to 150m with +-1mm~+-3mm accuracy. Also, other requirements can be customized, like distance sensor analog output,long range ir sensor. We will give you full technical support when you testing our long distance sensor.

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