Fertilizer needs a long-term supply, and it is best to use it according to the physiological characteristics of the crop at various stages, and there is no need to blindly pursue quick-acting.

Generally speaking, the fertilizer validity period of fertilizer products is as follows (for reference only):

Ammonium bicarbonate: effective on the same day, the fertilizer effect period is 15 days;

Ammonium chloride: effective in three days, fertilizer effect period of 25 days, defertilization in the later stage;

Urea: effective in seven days, fertilizer effect period is 45 days;

Compound fertilizer: effective in ten days, fertilizer effect period is 90 days;

Biological fertilizer: generally effective in about one month, the effect is not very obvious on crops with long growth cycle, but the fertilizer effect can last for 6 to 8 months;

Hormones: It takes effect quickly, but it doesn't have much nutrition on its own, so it doesn't help much to increase production.