How to Apply Supplemental Fertilizer to Chrysanthemums

Chrysanthemums are fertilizer-loving plants with a large amount of growth and a long flowering period. Base fertilizer alone often cannot meet the nutrient needs of the entire growth period, so supplemental fertilizer is needed to replenish nutrients in time. When supplemental fertilizer is applied properly, the plants grow robustly with lush branches and leaves, and the flowers are large and brightly colored; when it is applied improperly, the plants are prone to leggy growth, root burn or bud drop, so mastering the method is crucial.

From the perspective of growth stages, supplemental fertilizer during the seedling stage should be mainly nitrogen fertilizer, and the concentration should be dilute, to promote seedling growth and the emergence of branches. After entering the period of vigorous branch and leaf growth, a thin liquid fertilizer that has been fully decomposed can be applied about every ten days, together with an appropriate amount of phosphorus and potassium fertilizer, to make the stems sturdy and increase branching. The bud stage is the peak period of fertilizer demand; at this time, more phosphorus and potassium fertilizer should be applied and the amount of nitrogen fertilizer should be controlled, which helps flower bud differentiation and bud development, making the flowers large and brightly colored.

As for the method of supplemental fertilization, a thin fertilizer solution can be poured on, or a shallow trench can be opened and the fertilizer buried in it; after burying, soil should be covered and water applied promptly. Fertilization should preferably be done in the evening on a clear day; loosen the soil appropriately before application, and the next day after application, water once with clear water to help the nutrients leach downward and avoid fertilizer accumulating around the roots and damaging them.

It should be noted that supplemental fertilization should follow the principle of applying thin fertilizer frequently, and raw fertilizer and concentrated fertilizer must never be used, to prevent root burn and root rot. Fertilization is not suitable during high summer temperatures or when the soil is too wet after rain, and if the fertilizer solution gets on the leaves, it should be rinsed off promptly with clear water. Supplemental fertilization should be stopped when flowering is approaching, to avoid bud drop or a shortened flowering period. In addition, supplemental fertilization can be combined with intertillage and weeding, and coordinated with routine management such as pest and disease control, so that the growth and flowering quality of chrysanthemums will be better.