What kind of fertilizer is good for the base layer? This will lead to higher crop yields.

There is another overlooked aspect of bottom fertilizer, which is that it can "treat diseases" for the soil. Look at it now. The land is tilled too frequently, and fertilizers and pesticides are heaped onto it in large quantities. Year after year, the land becomes "stiff" - compacted, saline-alkali, and acidic. All kinds of problems surface. In the past, the black soil was soft. Now, when seeds are sown and a hoe is used to break the soil, it is so hard that it feels like it's made of stone. The "vitality" of the soil has vanished. At this point, the task of bottom fertilizer is to add some organic matter to the soil, replenish bacteria, replenish nutrients, and enhance activity. This will enable the land to come back to life, and the crops will have a strong root system.

Just knowing that the base fertilizer is good is not enough. The real problem arises here - how should the base fertilizer be selected? This depends on the type of crop and the specific plot. For example, in a greenhouse used for growing vegetables, if the same crop is grown year after year, there is no shortage of nitrogen, phosphorus, and potassium in the soil. What is lacking is soil activity and structure. If more and more chemical fertilizers are scattered haphazardly, the root cause of the problem will become deeper, and the soil will deteriorate even more. In recent years, this has often happened in the greenhouse areas of Hebei and Shandong. Outside the greenhouse, there are mosses and white salts, while inside the greenhouse, the vegetables become increasingly diseased, with one crop after another failing. 
So, when it comes to the bottom fertilizer strategy for greenhouse vegetables, the current focus is more on reducing salt content, adjusting pH levels, and achieving water-soluble fertilizer effects. Some manufacturers have developed products that are "chelated salts" to enhance efficacy. In simple terms, this means preventing the fertilizer from being completely locked up in the soil and allowing it to actually reach the crops. For example, when the Shanghai green vegetables were tested by veteran farmers, the seedlings grew robustly, with vigorous root systems, and the harvest could be significantly improved, with a strong post-harvest vigor.

Many people take the easy way out and purchase low-end fertilizers in an attempt to save money. As a result, much of the nitrogen, phosphorus, and potassium either gets fixed by the soil or evaporates quickly, causing waste on both ends. Looking at the green moss and white alkali on the soil surface, it is actually "false fertilizer". Not only do farmers feel the financial strain, but it also causes a host of problems. Moreover, the excessive accumulation of inorganic salts damages the roots of crops, preventing them from absorbing water and resulting in poor growth and wilting, which can be noticed immediately. 
If you have to choose the base fertilizer, the old method suggests that those uncompletely decomposed farmyard manure should be used sparingly. Think about it, untreated cow manure and chicken manure have high salt content and a lot of heavy metals, and without decomposition they can even cause root burning. Nowadays, many regions are more strictly inspecting this matter. If a family uses farmyard manure carelessly, they may lose a large area of seedlings, or even cause soil pollution. It's a huge loss for a single season, not just a little bit. Therefore, the qualified, organic, and properly treated commercial organic fertilizers in the market are the right choice. 
The current main combination of base fertilizer is as follows: use commercial organic fertilizer as the base, supplement with granular microbial agents to activate life, along with calcium, magnesium and other trace elements, and then add a balanced water-soluble fertilizer with good decomposition properties. In particular, the microbial agents with a high effective viable bacteria content, which can withstand salt, alkali, acid, cold and heat, and have strong adaptability. A few farmers in Xi'an, Shaanxi Province conducted a pilot program of this combination a few years ago. The soil improved significantly within two years, the growth of crops was visibly better, and the incidence of diseases was also reduced significantly. 
If the trace elements in calcium and magnesium are used properly, it can prevent nutrient deficiencies in vegetables and fruit trees in advance. From minor issues like yellow leaves and fruit cracking to major problems like root rot and premature aging - in many cases, weak seedlings are not caused by fertilizer issues, but rather by a lack of trace elements. Don't wait until the problems arise to think of making up for them. It will be too late by then. 
When applying bottom fertilizer, there is no universal formula. The type of fertilizer depends on the specific soil conditions and the needs of the crops. The key is to understand the soil quality of your land and the requirements of the crops, and avoid making one-size-fits-all assumptions. Try to combine and use them appropriately, and you will see the results. 
Farming has never been a job that relies on shortcuts. If you apply the right amount of fertilizer, the soil and the plants will both thrive.