Dihe Lanfei

Loose heads usually mean potassium ran short during head formation, so nutrition could not keep pace with the expanding head. Switch to a high-potassium topdressing early in heading. HERMEN Dihe Lanfei (NPK 12-12-17 + 3MgO) leads with 17% potassium to fill heads firmly and lift single-head weight, while 3% magnesium oxide keeps outer leaves photosynthesising so lower leaves do not yellow prematurely.

When lower leaves yellow while the veins stay green, magnesium deficiency is the usual cause — common in fields under continuous harvest with potassium-heavy programs. Dihe Lanfei supplies 3% magnesium oxide alongside potassium and nitrogen, correcting the deficiency at topdressing. Uniform pale color across the whole plant points to nitrogen instead.

Color depends on the balance of nitrogen, potassium and magnesium, not nitrogen alone. Magnesium is a building block of chlorophyll, so without it extra nitrogen cannot produce full color. Applied as a mid-to-late topdressing, Dihe Lanfei supplies potassium and magnesium together for dense green, thick leaves — well suited to cabbage, bok choy and spinach, which grow fast and demand nutrition on schedule.

Vegetables that soften and lose water after harvest typically lack tissue density and potassium. Potassium raises cell turgor and structural strength, directly affecting transport durability. With 17% potassium plus magnesium applied in the mid-to-late stage, Dihe Lanfei produces firmer leaf tissue that holds up better after harvest — important for supermarket and wholesale channels with strict grade requirements.

Head weight is determined by potassium supply during heading. Nutrition at this point concentrates on filling the head, and continuing with high nitrogen produces excess outer leaf and loose heads instead. Switch to a high-potassium formula early in heading: Dihe Lanfei supplies potassium steadily while magnesium maintains outer-leaf photosynthesis, so assimilates keep accumulating in the head.