Technical essentials of soil testing and fertilization of celery

Celery belongs to Umbelliferae. There are three kinds of water celery, celery and celery, which have similar functions, and it is better to use them as medicine. Parsley has a strong aroma, which is called "medicinal parsley". But it is not the same kind as cilantro. Celery is rich in protein, carbohydrates, carotene, B vitamins, calcium, phosphorus, iron, sodium, etc., at the same time, it has the effects of calming the liver and clearing heat, dispelling wind and dampness, dispelling swelling, cooling blood and stopping blood, detoxifying and relieving the lungs, invigorating stomach and blood, clearing intestines and defecation, moistening lung and relieving cough, lowering blood pressure, invigorating brain and calming. Often eat celery, especially eat celery leaves, to prevent hypertension, arteriosclerosis and so on are very beneficial, and have adjuvant treatment effect. In this paper, the key points of soil testing and formula fertilization for celery are introduced as follows:

The nutrient absorption of celery was high in the peak period of vegetative growth, and the absorption of nitrogen, phosphorus, potassium, magnesium and calcium accounted for more than 84% of the total absorption. Celery needs the highest amount of nitrogen, followed by calcium and potassium, followed by phosphorus and magnesium. Celery also has a large demand for boron. In boron-deficient soil or when absorption is inhibited by drought and low temperature, the petiole is easy to crack, that is, "stem folding disease", which seriously affects the yield and quality.

Under the medium fertility level, the amount of fertilizer applied to celery during the whole growth period was 25003000kg of farm manure (or 350kg / mu of commercial organic fertilizer), 1316kg of nitrogen fertilizer, 5kg of phosphate fertilizer, 69kg of potassium fertilizer, nitrogen and potassium fertilizer was divided into base fertilizer and three times topdressing, the proportion of fertilizer was 2 ∶ 3 ∶ 3 ∶ 2, all phosphate fertilizer was used as base fertilizer, chemical fertilizer and farm manure (or commercial organic fertilizer) were mixed.

Per mu of base fertilizer, 2500-3000 kg of farm manure or 350-400 kg of commercial organic fertilizer, 4-5 kg of urea, 11-13 kg of diammonium phosphate and 4-5 kg of potassium sulfate were applied.

Topdressing applied 6kg urea and 3kg potassium sulfate per mu in the heart leaf growth period after slow seedling, 811kg urea and 3kg potassium sulfate per mu in the early stage of vigorous growth, and 68kg urea and 3kg potassium sulfate per mu in the middle stage of vigorous growth.

If heart rot is found in extra-root topdressing, foliar spraying can be carried out with 0.3% 0.5% calcium nitrate or calcium chloride. Foliar application of boron fertilizer can avoid stem cracking to a certain extent, spraying 0.2% borax or boric acid solution 40kg / mu each time. Protected cultivation can increase the application of carbon dioxide gas fertilizer.