Balcony vegetables are thin and yellow again? Spray this water and they instantly turn glossy green and sturdy

Actually, many of the vegetables we commonly eat can be grown ourselves. If buying vegetables is not cost-effective, why not make use of the balcony space and grow some yourself. Pick and eat fresh, safe and fresh, and you can save quite a bit of money too.
Quite a few vegetable growers also plant many leafy vegetables on the balcony, such as baby bok choy, small rapeseed, lettuce, cilantro, scallions, garlic sprouts, Chinese chives, etc. These vegetables grow fast, taste good, and are not afraid of the cold. But after growing them for a while, people get discouraged: other people's are tall and sturdy with green leaves. Their own are yellow and thin, with no marketable look at all. What is going on?
Because growing vegetables on a balcony is different from open-air field planting, light and ventilation both have certain limitations, so it is a bit difficult to get them plump and sturdy. But an experienced vegetable grower shared a little trick with us that can make balcony vegetables glossy green and sturdy, with double the yield.
That is spraying potassium dihydrogen phosphate solution. Potassium dihydrogen phosphate solution is a phosphorus-potassium fertilizer that can promote plant flowering and fruiting, and strong roots.
Specific operation: for potted leafy vegetables, once they grow to three or four leaves after sowing, you can spray this foliar fertilizer. If the leafy vegetable's growth cycle is only about one month, then spraying two or three times is enough.
Spraying precautions: the concentration of the sprayed potassium dihydrogen phosphate is 0.3-0.5%. For foliar fertilization, the spraying must be even, and both the front and back of the leaves must be evenly sprayed to absorb better.