Manure has some potential disadvantages when used as fertilizer. It can contain weed and pest seeds, rodents and other pests, and pathogens such as E. coli. It can also cause pollution if not managed properly, as the manure may flow into the surface or groundwater.
Manure is often disposed of in piles, slurries or lagoons, which can lead to significant emissions of the greenhouse gas methane, as well environmental degradation, negative health impacts, and the loss of valuable nutrients that could be added to soil.
Manure adds nutrients to the soil without affecting its fertility. It does not damage crops and produces healthy plants. Fertilizers are chemicals which lower the fertility of the soil if used regularly. They also damage the crops and make them unhealthy for consumption.
Adding manure to soil improves the soil's texture and water-holding capacity while providing nutrients needed by growing plants. Unfortunately, fresh manure can also contain bacteria that can contaminate vegetables and cause human disease.
Applying too much manure, at the wrong time, or improperly handling it in other ways releases nutrients into the air or into ground or surface waters. Thus, instead of nourishing crops, nutrients become pollutants. Excess nitrogen can leach through soil into groundwater.
Don't Use Fresh Manure
If the manure is from a plant-eating animal, it is probably also full of weed seeds, which will not be inhibited from sprouting. If you still want to make use of fresh manure, don't apply it after your garden has been planted.
The advantages of using farmyard manure are that it's readily available, cheap, and easy to use because it's hard to overuse it. The disadvantages are that it has to be transported, doesn't smell too good, and requires consistent levels of certain organisms in the soil to break it down.
Manure is derived naturally and adds a lot more than just nutrients to the soil. They increase the activity of the microbes in the soil and increase its fertility. On the other hand, fertilisers harm these microbes and cause health issues in the consumers since they are synthesised chemically.
Proper use of manure as a fertilizer minimizes nutrient pollution to water resources and helps build healthy soils. Manure nutrients can also be used to grow worms, insect larvae, algae, or other living organisms.
Excess use of fertilizers causes environmental pollution as their residual and unused amounts will become pollutants for air, water, and soil. It also initiates the process of eutrophication in the water bodies, decreasing the soil quality by killing the soil microflora, etc.
Animal manure applications can increase soil organic matter in medium / long term application periods. Consequently, manure contributes to reducing soil bulk density and compaction, as well as increasing soil aggregate stability, water infiltration and retention.
A disadvantage of composting is that some of the ammonia-nitrogen will be lost as a gas. Alone, compost may not adequately supply sufficient nutrients—particularly nitrogen during rapid growth phases of crops with high nutrient demands (e.g., watermelon, tomato, and pepper at fruiting) (Tyson and Cabrera, 1993).
Manure does not always contain as many nutrients as fertilizers. Manure is mainly based on an animal's diet and can only be created when they lay waste. Whereas Fertilizers are made in an industrial environment. Manure is organic whereas fertilizers are a synthetic product.
Both are some of the best resources of nutrients for organic crop farmers, making it easier to earn and maintain your organic certification. They both also increase your soil's water retention. However, cow manure is typically more expensive and contains fewer nutrients than chicken manure.
If, for example, your main goal is to increase your soil's organic matter, compost is likely the right pick, whereas if you're looking to boost your soil's nutrient content, manure is your better bet.
Blending manure into the top layer of topsoil will help encourage root growth and health because the manure is packed full of nutrients. The main nutrient released is nitrogen which is needed for plants and vegetables to grow in a sustainable manner.
Adding manure to the home vegetable garden can increase soil organic matter and may alter soil structure. Adding manure to soil will not change soil texture. Fall is the most common time of year for adding manure to a vegetable garden. The manure may be spread atop the soil or incorporated into the garden soil.
Disadvantages of Manure
The manures are reported to provide fewer nutrients to plants, and they are unable to provide high-yielding crops. Manures are slowly absorbed by the plants, and they add a lot of humus to the soil. They are made in fields, so transportation is difficult for manures.
Manure is typically between pH 8-12, but don't expect manure to affect pH levels in soil. The pH scales ranges from 0 to 14, where 7 is neutral, below 7 is acidic, and above 7 is alkaline or basic. Each whole unit (1.0) is a ten-fold difference in the level of acidity.
Manure not only acts as a source of plant nutrients but, through the addition of organic matter, it also helps to improve soil tilth, structure, aeration and water holding capacity. Manure application is a sustainable agricultural practice.
Manure that is piled and left alone will decompose slowly. This can take three to four months if conditions are ideal. It can take a year or more if the starting material contains a wide carbon:nitrogen ratio (as is the case when manure contains wood chips).