How to prevent and treat yellowing leaves in flowers caused by acidic soil?

For the causes of leaf yellowing caused by acidic soil, the following 3 major preventive and control measures can be taken:

1. Increase the supply of soluble iron: if the soil and water are alkaline, acidic fertilizers such as ammonium sulfate can be applied, mixed with 0.1% gypsum or sulfur powder, which helps reduce alkalinity and improve the availability of iron.

2. Increase the supply of magnesium: in acidic soil areas, apply calcium magnesium phosphate fertilizer, or spray the leaves with a 0.1%-0.5% magnesium sulfate solution, which can turn the leaves green again.

3. Supply nitrogen fertilizer in time: for flowers planted in the ground, apply sufficient organic fertilizer in winter (cake fertilizer, garbage mud, etc.); for potted flowers, apply a 0.1%-0.2% solution of urea or ammonium sulfate as a top dressing in spring. In addition, flowers planted in the ground should be drained in time, and potted flowers should have a drainage layer placed underneath, taking care that the soil has good aeration.