Can old soil left after repotting flowers still be used to grow flowers?

As a flower lover living in a city, in a jungle of steel and concrete, growing flowers and plants makes the source of soil itself a big problem. It is really not easy to get some free, decent soil for growing flowers and plants. Every time I go out I take a bag with me, and when I see a bit of leaf mold under a tree, I hope I can bag it and take it home for my flowers. I think most friends who grow flowers understand this feeling!

The old soil left after repotting flowers can, of course, be used to grow flowers and plants. Not only can it be used, I will definitely make use of it. But when using old soil, you should give it a simple treatment first and then use it for growing flowers, and the result will be better. Below I will talk about what defects the old soil left after repotting flowers has, what benefits it has, and how it should be treated and used, hoping it can help flower lovers who need it.

What defects does the old soil that has been replaced have?

1. Lack of nutrients. This is actually easy to understand; you can first think about why we repot flowers. Generally, under normal circumstances, there are two main reasons: 1. The original flowers and plants have grown in one pot for one or two years, and the nutrients in the soil are no longer enough to supply the normal growth of the flowers and plants; 2. The root system of the original flowers and plants has grown vigorously in the pot and has already filled the entire pot, so the roots do not have enough space to grow. Seeing the first reason, you will understand that a large part of the nutrients in the old soil after repotting has already been absorbed by the original host for growth. The remaining nutrients should be very few. If it is used directly to grow flowers, it will inevitably cause the later plants to lack a nutrient foundation;

2. It may carry pathogens and insect eggs. The flowers and plants in the original pot, during long-term care, will inevitably produce more bacteria in the soil. These bacteria may already be adapted to the original flowers and plants, but for the later plants, they may be fatal. At the same time, the original flowers and plants, during long-term care, are very likely to leave behind various harmful insect eggs. These insect eggs may very likely break out in the future and become pest problems for the later plants. Of course, these are only possibilities, not certainties, but it is always good to take preventive measures before use. In all things, preparation leads to success, and lack of preparation leads to failure.

3. The water retention of old soil will be somewhat poorer. When the old soil in the original pot was used to care for the original flowers and plants, during long-term care, with constant watering and the plants constantly absorbing water, the water-retaining substances in the soil will be continuously broken down and lost. To put it simply, this is soil erosion. This will cause the remaining old soil to have a relatively much higher content of large particles, and its drainage will be very good, but its water retention will be much poorer.

Everything has two sides. Having finished talking about the defects of the old soil left after repotting flowers, now let us talk about the benefits of this old soil:

1. The first and greatest benefit, of course, is saving. It is really a pity to throw this old soil away directly. Apart from having somewhat fewer nutrients, it has no major defects. Besides, the amount of nutrients is only relative. The nutrients in old soil are diverse, and the nutrient elements that the original flowers and plants needed to absorb are not necessarily what the next plant needs. What it does not need may be exactly what the next plant needs most.

2. This kind of old soil will be relatively looser and have somewhat better drainage. This point was also mentioned in the first section: most of what remains after soil erosion is large-particle material, and the drainage will be relatively much better. In addition, during the care of the previous flowers and plants, a lot of dead capillary roots and fallen leaves will remain. During long-term care, these organic materials have already rotted and become high-quality organic fertilizer, which has a very good improving effect on the soil. It will make the old soil looser and contain a small amount of organic matter;

Having talked about the benefits and drawbacks of old soil, now let us talk about how to use old soil correctly.

1. The first step, of course, is to disinfect and sterilize it and kill insect eggs. The simplest and most effective method is sun exposure. If you have outdoor conditions, you can put the old soil under strong sunlight for three to five days, turning it several times during that period, and the sterilizing and insect-killing effect will be better. The second simple method is to use fungicides and insecticides for disinfection. Directly mix an appropriate amount of carbendazim powder and Xiaobaiyao, Tuchongdan, etc. into the old soil, and they can all have a fairly good effect;

2. Mix in new substrate. After the old soil has been sterilized and dewormed, it can be used directly to grow flowers and plants. At this time, according to the structure of the old soil and the type of new plant to be grown, mix in different types of new growing media. For example, when growing succulents, you can mix in some granular material (perlite, vermiculite, etc.), and then mix in a small amount of peat soil. For example, when growing spider plants, you can mix in some peat soil. The ultimate goal is to achieve the type of growing medium required by the newly planted plants and to achieve a balance of water retention, drainage, looseness and nutrition. That is, by using the old soil, reducing the amount of new soil used, while also meeting the growth needs of the new flowers and plants.

Summary: The old soil left after repotting flowers can, of course, be used to grow flowers and plants. But when using old soil, you should give it a simple treatment first and then use it for growing flowers, and the result will be better. Disinfecting and sterilizing it and killing insect eggs is the first step, and the simplest and most effective method is sun exposure. The second step is to mix in an appropriate amount of new soil so that it meets the growth needs of the newly planted flowers and plants.