fertilizer experimental design

例句：

1. 1. The soil in the garden needs to be regularly fertilized to ensure it has enough nutrients for plants.
   花园里的土壤需要定期施肥，以确保植物有足够的养分。
2. 2. Tomatoes need a balanced diet of nitrogen, phosphorus, and potassium to grow well.
   西红柿需要氮、磷和钾的平衡饮食才能健康成长。
3. 3. Fertilizers are essential for plant growth and development.
   肥料对于植物的生长和发展至关重要。