Cow manure is a great soil conditioner, adding organic matter and structure to garden soil. As a cow's diet is mostly grass, their poo tends to be low in nutrients, so they are ideal for native gardens or vegetables that don't need much food such as onions, carrots, parsnips, and beetroot.
Cow manure is rich in nutrients and is suitable for plant growth. It has 3% nitrogen, 2% phosphorus, and 1% potassium—3-2-1 NPK, making it the right type of fertilizer for almost all types of plants and crops.
Cow manure has low values of nitrogen, phosphorus, and potassium. It is ideal as a top dressing and a compost IF IT IS ROTTED. If it is not composted and is still fresh, you might burn your plants. NEVER put fresh manure on a plant unless you want to kill the plant.
With just a four month or so growing season, this means you should only apply fresh manure in the fall; not in the spring or during the growing season to any area that is or will be planted with food crops. Composting manure eliminates some of the problems of fresh manure — including the odor.
Plants don't need to wait as long for manure's nutrients as for compost's – it's the fast-food option of the 2. Manure also tends to have more nutrients than compost. But be aware that you must be more careful when using manure than compost because of its risks.
First of all, you should avoid using fresh or un-composted raw manure on all your fruits and vegetables. Mainly the root vegetables such as radish, carrot, beetroot, and potato. It can burn and damage your crops. But, this is not the case for composted animal manures.
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 contamination can increase nitrate levels in ground water and cause bacterial contamination and fish kills in surface waters. Excess phosphorus can be contained in erosion or runoff from fields and accumulate in surface water impoundments such as ponds and lakes.
For best management practices, manure should be applied to a garden no later than 90 days prior to harvest of non-ground-contact crops such as trellised tomatoes, cucumbers and peppers; and no later than 120 days prior to harvest of ground-contact crops such as lettuce, strawberries and carrots.
The manure may be spread atop the soil or incorporated into the garden soil. Pig, dog, cat, and human waste should never be used in a vegetable garden. Cow, horse, chicken/poultry, sheep, goat, and llama manure are acceptable types of manure appropriate for use in vegetable gardens.
Spreading or digging in raw manure is an option in the fall, because more than four months (120 days) will pass before the manured soil produces an edible crop. By then the manure will have decomposed and pathogenic Salmonella and E.
Another of the cons of using manure fertilizer is that it can raise the acidity of soil over time while also depleting calcium, an essential mineral for plants. Manure needs to be tilled into be most effective. The very action bares soil and leaves it open to further leaching and topsoil loss.
What to use? There is no “best” top-dressing material for your lawn. Some people use mushroom compost, some people use peat moss, some use composted cow manure, some use their own compost. Depending on what kind of soil you already have, you may want to mix it with bagged topsoil or sand.
Salt is also prevalent in manure and, over time, can build up in the soil. High levels of salt in the soil can create dry conditions and damage the roots of plants. Trees and plants may be subject to diseases when planted in soil with a high concentration of salt as well.
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.
Manures are obtained from natural sources, whereas fertilisers are synthetically manufactured in the factories. Manures are eco-friendly, whereas fertilisers harm the useful microbes present in the soil and also decrease the soil fertility if used for a longer time.
Fresh manure breaks down faster than composted manure.
Not all manure provides nutrients to plants. As it breaks down, manure containing lots of bedding takes nitrogen from the soil. This reduces the amount of nitrogen available to plants.
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).
Difference between Manures and Fertilizers
Manure is obtained naturally by the decomposition of dead plants and animals. Fertilizers are chemical substances and are not typically natural. It is not very rich in nutrients. It is rich in soil nutrients like nitrogen, phosphorous, and potassium.
Manure can contain human pathogens and through its use near fruits and vegetables, it can spread human pathogens to produce. Pathogens harmful to humans that are often found in manure include: pathogenic E. coli, Salmonella, and Listeria monocytogenes.
Simply ageing a manure pile for three months can kill about 60% of the weed seeds present, and bacterial counts start to drop within days after the manure leaves the animal. Then, when the aged manure is mixed into the soil, soil microorganisms clear out residual bacteria in about a month.
When properly used, manure eliminates the need to apply chemical fertilizer, since they both supply, the three major nutrients needed by plants: nitrogen, phosphorus and potassium. Here is another article specifically devoted to fertilizers: Fertilizing Your Garden.
Spring is the preferred time to apply manure. Forage or hay crops generally provide the greatest flexibility in planning land application operations.