1. Application sites. Generally, tender leaves are prioritized as they have stronger absorption capabilities; for dicot plants, spray both the front and back, while for monocot plants, spray the front from top to bottom. Nitrogen and potassium are mobile elements and can be sprayed on the lower part, whereas calcium, boron, iron, and copper are less mobile elements, and should be applied to new leaves.
2. Application Time: Foliar fertilizer is generally applied before 10 AM and after 4 PM on windless evenings. It is not suitable on rainy days, before rain, or in the morning with dew. If it rains within 3 hours after application, a top-up application should be made on a sunny day.
3. Fertilization Stage. Appropriate Timing: Spray foliar fertilizer is suitable during pest and disease outbreaks, poor soil conditions, peak fruiting period, and when encountering frost or heat stress; Unsuitable Timing: It is not advisable to spray foliar fertilizer during flowering or seedling stages.
4. Fertilizer Mixing: When applying foliar fertilizers, it's common to mix various types of fertilizers together. However, it's crucial to ensure that the mixture does not cause adverse reactions or reduce the effectiveness of the fertilizer. Additionally, when blending foliar fertilizers, attention must be given to the solution's concentration and pH level. Generally, a neutral pH of 7 is beneficial for leaf absorption.