Neem cake organic manure is the by-product obtained in the process of cold pressing of Neem

Neem

Azadirachta indica is a tree in the mahogany family Meliaceae. It is one of two species in the genus Azadirachta, and is native to India growing in tropical and semi-tropical regions. Its fruits and seeds are the source of neem oil...

 tree fruits and kernels, and the solvent extraction process for neem oil

Neem oil

Neem oil is a vegetable oil pressed from the fruits and seeds of the neem , an evergreen tree which is endemic to the Indian subcontinent and has been introduced to many other areas in the tropics...

 cake.
It is a potential source of organic manure under the Bureau of India Standards, Specification No. 8558. Neem has demonstrated considerable potential as a fertilizer. For this purpose, neem cake and neem leaves are especially promising. Puri (1999), in his book on neem, has given details about neem seed cake as manure and nitrification

Nitrification

Nitrification is the biological oxidation of ammonia with oxygen into nitrite followed by the oxidation of these nitrites into nitrates. Degradation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil...

 inhibitor. The author has described that, after processing, neem cake can be used for partial replacement of poultry and cattle feed.

Components

Neem Cake has an adequate quantity of NPK in organic form for plant growth. Being a totally botanical product it contains 100% natural NPK content and other essential micro nutrients as N(Nitrogen 2.0% to 5.0%), P(Phosphorus 0.5% to 1.0%),
K(Potassium 1.0% to 2.0%), Ca(Calcium 0.5% to 3.0%), Mg(Magnesium 0.3% to 1.0%), S(Sulphur 0.2% to 3.0%), Zn(Zinc 15 ppm to 60 ppm), Cu(Copper 4 ppm to 20 ppm), Fe (Iron 500 ppm to 1200 ppm), Mn (Manganese 20 ppm to 60 ppm). It is rich in both sulphur compounds and bitter limonoids.

According to research calculations, neem cake seems to make soil more fertile due to an ingredient that blocks soil bacteria from converting nitrogenous compounds into nitrogen gas. It is a nitrification inhibitor and prolongs the availability of nitrogen to both short duration and long duration crops.

Use as a fertilizer

Neem cake organic manure protects plant roots from nematodes, soil grubs and white ants probably due to its content of the residual limonoids. It also acts as a natural fertilizer with pesticidal properties. Neem cake is widely used in India to fertilize paddy, cotton and sugarcane. Usage of neem cake have shown an increase in the dry matter in Tectona grandis (Teak

Teak

Teak is the common name for the tropical hardwood tree species Tectona grandis and its wood products. Tectona grandis is native to south and southeast Asia, mainly India, Indonesia, Malaysia, and Burma, but is naturalized and cultivated in many countries, including those in Africa and the...

), Acacia nilotica (Gum Arabic

Gum arabic

220px|thumb|right|Acacia gumGum arabic, also known as acacia gum, chaar gund, char goond, or meska, is a natural gum made of hardened sap taken from two species of the acacia tree; Acacia senegal and Acacia seyal...

), and other forest trees.

Neem seed cake also reduce alkalinity in soil, as it produces organic acids on decomposition. Being totally natural, it is compatible with soil microbes, improves and rhizosphere

Rhizosphere (ecology)

The rhizosphere is the narrow region of soil that is directly influenced by root secretions and associated soil microorganisms. Soil which is not part of the rhizosphere is known as bulk soil. The rhizosphere contains many bacteria that feed on sloughed-off plant cells, termed rhizodeposition, and...

 microflora and hence ensures fertility of the soil. Neem Cake improves the organic matter content of the soil, helping improvement in soil texture, water holding capacity, soil aeration for better root development.

Pest control

Neem cake is effective in the management of insects and pests. The bitter principles of the soil and cake have been reported to have seven types of activities (a) antifeedant (b) attractant (c) repellent (d) insecticide (e) nematicide (f) growth disruptor and (g) antimicrobial.

The cake contains salannin, nimbin, azadirachtin and azadiradione as the major components. Of these, azadirachtin and meliantriol are used as locust antifeedants while salannin is used as an antifeedant for the housefly.