1. The expired yogurt can't be watered directly. At this time, the fertilizer is called raw fertilizer, which is easy to cause fertilizer damage, which will cause root burning and insects to be harmful to plants.

2. Usually, directly watering flowers with yogurt will form a white lump on the soil surface, which will affect the beauty of flowers. You can put the expired yogurt in useless plastic bottles, ferment it for a while and dilute it. Then dig a small pit with a spatula, then pour the diluted yogurt and fill it with soil, which can make the flowers better absorb the nutrients in the yogurt, and then the flowers will be lush and very gratifying. If it smells bad, you can put a few pieces of orange peel after fermentation, which can effectively reduce the odor.