Growing flowers without buying nutrient soil: just pick up some "trash" and put it in the pot, and the flowers will bloom nonstop

A friend replaced a bunch of potting soil and wanted to reuse it by planting newly bought flowers in it. But can nutrient soil be reused?
Nutrient soil cannot be reused! At the very least, it cannot be reused before being disinfected and blended. Because nutrient soil is the basic guarantee for plant growth, and if it is reused, the nutrients have all been absorbed, so what guarantee is left!
After nutrient soil has been used for a period of time, the deposited substances in it can easily make the soil compacted, or it can become extremely easy to get damp, and it may also breed bacteria due to long-term use, so it is not recommended to reuse it.
If you really are short of this potting soil, then it must be treated before it can be used again. You can put it under the sun to bake for several days, letting it repeatedly receive sunlight; after sterilization and disinfection, mix in half garden soil or leaf mold to meet the standard for use
In fact, nutrient soil is very easy to obtain. As long as you take a walk in the wild, free nutrient soil is everywhere:
Leaf mold
In the woods, collect the fallen leaves that have been exposed to wind and rain, take them home, layer fallen leaves and garden soil, wet them with water, seal them after wetting, and put them in a corner. Once they are fully decomposed, they become very easy-to-use nutrient soil.
You can also go to a roadside in the countryside and find a woodpile, lift up the firewood, and dig out the rotted black soil in the layer underneath. This is truly decomposed fertile soil. Bring it back and put it in the sun for several more days, and it can be used. The effect is very good; I have used it!
Peat soil
Go to the edge of a lotus pond and dig back some blackened, carbonized river mud. After sun-drying and sifting, it is very good peat soil, with many nutrients, fertile and durable.
There are also pine needle soil, garden soil, and sawdust soil, which are also very easy to obtain. After processing and treatment, they are all very easy-to-use nutrient soils. For planting flowers and growing vegetables, the effect is very good. And they cost no money, and when used to grow flowers, they bloom like crazy