A Detailed Guide to Fermenting Farmyard Manure and Mixing It with Chemical Fertilizers

Farmyard manure is abundant in sources, comprehensive in nutrients and stable and long-lasting in fertilizer effect, but it contains low levels of nutrients and has a slow fertilizer effect. Chemical fertilizers have high nutrient content and a rapid, strong fertilizer effect, but their nutrients are relatively single. So how is farmyard manure fermented? And what are the methods for mixing it with chemical fertilizers?

1. How is farmyard manure fermented?

1. Build the collected farmyard manure into a heap. It should be 1.5 m wide and 1 m high (with layers about 10 cm thick). Spray each layer with carbendazim, chlorothalonil, avermectin or granular insecticides to kill insects and eggs; you can also combine this with microbial agents such as fermentation starter to promote fermentation (fungicides cannot be mixed with microbial agents; choose one of the two).

2. After building the heap according to the above standards, coat it with mud slurry and cover it tightly. You must not skip the covering measures, otherwise the temperature inside the heap will rise too slowly and it will not kill insects or sterilize; nor should you cover it too tightly with plastic film, otherwise after the temperature inside the heap rises, the harmful gases inside cannot escape.

3. Turn the heap after half a month. After half a month, turn and toss it once, then coat it with mud slurry. This turning does not need to be layered like the first time, nor do you need to spread fungicides, insecticides or biological agents.

4. After another half month, turn and toss it once more as in step three. That is, a total of three turnings is all that is needed. (Notes: Building a heap in winter requires a slightly longer composting time; in summer, when it rains, check whether the applied mud slurry has been washed away.)

In summer, the turning and fermentation time is about 30 days, while in winter the fermentation period is about 60 days.

2. Principles for mixing farmyard manure with chemical fertilizers

Not every kind of farmyard manure can be mixed with chemical fertilizers. Because different chemical fertilizers have different properties, improper mixing will instead cause nutrients to be lost and reduce fertilizer effectiveness. Therefore, mixing should follow the two principles below.

1. After two or more fertilizers are mixed, none of the nutrient components should be reduced; instead, the physical properties of the fertilizer should be improved;

2. The proportion of nutrient types in the mixed fertilizer should suit the crop's nutritional needs and the soil fertility status, so as to help improve fertilizer effectiveness.

3. How are farmyard manure and fertilizers mixed?

(1) Fertilizers that can be mixed and used

1. Except for ammonium nitrate, all chemical fertilizers such as superphosphate and phosphate rock powder can be mixed with compost and barnyard manure;

2. Physiologically acidic chemical fertilizers such as ammonium chloride and ammonium sulfate can all be mixed with phosphate rock powder;

3. Ammonium nitrate and potassium chloride can be mixed. The benefit of mixing these fertilizers is to improve the effectiveness of nitrogen, phosphorus and potassium fertilizers, improve the physicochemical properties of the fertilizer, and make application convenient, saving time and labor.

(2) Fertilizers that should be used immediately after mixing

There are mixtures of superphosphate and nitrate nitrogen fertilizers, such as ammonium nitrate and ammonium phosphate nitrate; urea mixed with potassium chloride; and plant ash mixed with potassium salt fertilizers. After these fertilizers are mixed, they must be applied promptly. If stored too long, they will cause loss of available nutrients or deterioration of physical properties, becoming hygroscopic and caking, and unusable.

(3) Fertilizers that cannot be mixed and used

All ammonium nitrogen fertilizers, such as decomposed human and animal excreta, ammonium bicarbonate, ammonia water, ammonium sulfate, ammonium chloride and ammonium nitrate, should not be mixed with alkaline fertilizers such as plant ash, lime and steel slag phosphate fertilizer; superphosphate generally should not be mixed with alkaline fertilizers such as lime and plant ash. After these fertilizers are mixed, they easily cake and easily lose ammonium, causing even greater nutrient loss.