But I know you must have mentioned a ratio in the book or in the teacher, and how much to use.

1 First of all, you should test the content ratio of each element in the soil (you must have this if you write a paper). If it is an ordinary course, this can be ignored. If it is potted, collect local soil samples to prevent soil influence. If it is land, divide it into communities (each community 1 square meter, depending on your specific situation) and then decide to do several groups of experiments.

2 When planting each plot, for example, the first plot is1; 0.5; 1 (this is the approximate proportion of nitrogen, phosphorus and potassium in cotton) and then see if you do the effect of each fertilization or the effect of one fertilization on him.

If it is a one-time application, such as at seedling stage, the second plot will be applied for ten or twenty days, then the third plot will be applied again, and so on (it is suggested that flowerpots should be applied at special periods, such as flattening cotyledons, and what kind of performance should be shown in each period) (you should know what I mean).

4 If you only measure the influence of other proportions on Chinese cabbage, you can design your own proportion, such as1; 1; 1, 1; 0.5; 1 suggested gradient.

Just now, I checked the standard ratio of Chinese cabbage: "Every 1000kg Chinese cabbage absorbs about (N)2.2kg, (P2O5)0.94kg and (KO2)2.5kg". Make a blank control according to this ratio, and then mix around here by yourself. This is an experiment to see if the ratio is good. You can mix it boldly, but don't deviate too much around here. 0.94; 2.5 This is for comparison.