Detailed Explanation of Key Points of Foliar Fertilization Techniques for Potted Flowers

Foliar fertilization of flowers, also called root-outside fertilization, is a fertilization method in which a diluted solution of chemical fertilizer or trace elements is sprayed onto the leaf surface of flower plants and absorbed and utilized by the plants through leaf stomata. With root-outside fertilization techniques, the fertilizer is not fixed by the soil after application, nor is it affected by the absorption function of the root system; its advantages are a small amount of fertilizer used, rapid absorption, and remarkable fertilizer effect.

1. Suitable fertilization period

① It is usually applied during the vigorous growth period of flowers or when the plants lack a certain element; generally, fertilization can be carried out except during the flowering period.

② Choose a clear and windless day, and spraying in the morning or evening is preferable, because the leaf surface often has dew in the morning and evening, and the fertilizer solution is easily absorbed.

③ For foliar fertilization, spray more on the underside of the leaves, because there are many stomata on the underside of the leaves and the absorption effect is good.

④ Root-outside fertilization can be combined with pest and disease prevention by mixing pesticides, so as to achieve the purpose of simultaneously controlling pests and diseases.

2. Fertilization concentration

① The fertilizer solution concentration is preferably 0.1%-0.5%; if the concentration is too high, it will "burn" the leaves.

② Foliar fertilization is done once every 7-10 days; after fertilization it can be absorbed within 5 hours, within 24 hours absorption can reach 50%-70%, and the fertilizer effect can last 7-10 days.

3. Commonly used foliar fertilizers for flowers and application techniques

① Humic acid foliar fertilizer, such as Yemianbao, etc.

② Urea. It is the neutral chemical fertilizer with the highest nitrogen content, and a spraying concentration of less than or equal to 1% is relatively safe.

③ Potassium dihydrogen phosphate. The spraying concentration is preferably 0.1%-0.5%; root-outside fertilization can be carried out from the beginning of flower bud differentiation until budding, which is beneficial to flower bud differentiation, can make the flowers large, and makes the flower colors bright.

④ Superphosphate. The spraying concentration is preferably 0.5%-1%; it can make the plant leaves dark green, the flowers bloom with bright colors and open earlier; it promotes the growth of bulbous flowers, making the bulbs large and plump. Root-outside fertilization can be carried out from the beginning of flower bud differentiation until budding, which is beneficial to flower bud differentiation, can make the flowers large, and makes the flower colors bright.

⑤ Ferrous sulfate, also known as black alum. It contains trace elements such as iron and sulfur, and the spraying concentration is preferably 0.2%-0.5%; for flowers that prefer acidic soil, such as rhododendrons, camellias, gardenias, and banana shrubs, applying it when symptoms of iron-deficiency yellowing and small leaves appear gives very good results.

4. Precautions ① For foliar fertilization of flowers, the concentration should not be too high, otherwise it will "burn" the leaf surface. ② Spraying in cloudy and rainy weather has a relatively large impact on the fertilizer effect. ③ It should not be applied in windy weather or under scorching sun, so as to avoid fertilizer damage.