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Fish Blood and Bone Meal Fertilizer


What is Fish Blood and Bone Meal Fertilizer?

The organic fish blood and bone meal is a slow release fertilizer. Blood fish and bonemeal will not only strengthen garden plants, lawns, fruits and vegetables, it also improves the soil, the life of the bacteria in the soil and beneficial fungi such as mycorrhyza and micro bacteria. Blood bone and fish meal cannot be taken up by the plants unless transformed (mineralisation) from its organic state into an an-organic one by bacteria. Mineralisation happens only when the conditions in the soil are right. It depends very much on the temperature of the soil, the water content, the pH, the amount of organic material, the time of application and the carbon in the soil. It is important to use the fertilizer when the plant demands it. Each soil has also a saturation level of nutrients it can absorb: when there is too much fertilizer in the ground the plants will not use it and the precious fertilizer will run off or leach. Soil bacteria use some of the fertilizers, in particular fish meal, for their own growth and well being which encourages early season microbial life.


Uses of fish blood and bone meal

When to use fish blood and bone meal? And how do we use it? Blood fish and bone meal has many uses: when you plant, when you mix soil and make compost or use it in potting compost. You can use it as a general fertiliser or as a lawn fertilizer and so on.


Best is to apply fish bone and blood fertiliser just before plants start to grow vigorously and produce vegetative growth. When using the fertilizer you have to take into account the time it takes for the fertilizer to reach the roots and the time it takes for the soil micro organisms to process the fertilizer and make it ready to be used. You can use bone meal on its own well in advance when you prepare the soil for next year in autumn.

The plant decides how much fertilizer it will take up and when. For instance once the plants start forming fruits they will need less nitrogen because there is less need for abundant green growth. At that stage the plant will just ignore nitrogen. It would then be a waste of time and money to apply a fertilizer high in nitrogen.The fertilizer would only leach away into the ground water and probably end up polluting streams and rivers. Over-fertilizing increases the risk of 'burning' the plant leaves.

How much fish blood and bone meal do we use? We don't use a lot. As a general rule you can use a level spoon full per plant and about 100 gr per square meter when used on the lawn for instance.

Beneficial use if fish blood and bone meal

You can use fish blood and bone for garden trees, plants, bulbs and corms. It is also recommended to be used for growing herbs, fruits and vegetables. Blood meal for instance is an excellent organic supplier of relative slow release nitrogen, creating healthy green growth when needed. Bone meal strengthens the plant cells and fish meal does both. All three have other beneficial effects on the health of plants. The other advantage of using fish blood and bone is that the uptake of the fertiliser by plants makes the plants create leaves with high amounts of healthy vitamins and micro nutrients. Cucumber leaves for instance contained the following trace elements after an application of fish meal:Na, Cl, B, Cu, Fe, Zn, Mo, Mg, S, Ca, Mn.

Level of Nitrogen, Phosphorus and Potassium in fish blood and bone

The levels of nutrients in blood fish and bone vary greatly when they are mixed. They vary individually as well. The differences are caused by: the age of the organic fertilizer, the method of application, the time exposed to the weather elements, the soil type, the way it has been prepared and so on. Each batch should be individually measured on the amount of fertilizers.

  • Fish meal when heath dried has a complete N:P:K: of 10:6:2, but as said before, this varies between each batch. It also contains trace elements.

  • Blood meal has an average N:P:K of 12:1:1

  • Bone meal has an average N:P:K of  3.5:18:0

Fish blood and bone makes roots grow stronger

Blood fish and bone strengthens roots of plants. A stronger and deeper root system results in better plant growth, better crops and healthier and improved soils. When there is a lack of fertilizers in the soil, roots will produce many side-hairs to look for and extract as many nutrients they can find and extract from the soil. Most of these nutrients are then used for the growth and up-keep of these additional roots.

FISH MEAL FERTILIZER as ingredient of fish blood and bone meal

Fish meal is more than just leftovers from fish-trimmings and bones. Fish meal is big business. The demand for it is greater than the demand for fish for consumption. Fish, fish-bones and fish trimmings are dried, pressed and grounded into the powder fish meal..

Fish meal can be used as lawn fertilizer together with blood and bone meal. Fish blood and bone meal fertilizer contains a high amount of Nitrogen which will make the grass green up and grow. But it is not an explosive growth as would happen when artificial Nitrogen is used. It also enriches and strengthens soil life. For these reasons is it beneficial to use fish blood and bone meal fertilizer meal as a lawn fertilizer.


Fish meal contains a high amount of nitrogen which through mineralisation is taken up by the plant roots as a slow release fertilizer. It works very well not only with leafy plants like grass and lettuce but also with tomatoes for instance. Fish meal is suitable for all fruits, plants and vegetables.


When we apply fish meal to a contaminated soil bacteria that degrade harmful products like petrol, diesel or oil feed on it and thrive. It also reduces root rot. A plant attacked by root rot is unable to take up nutrients and will die off. Root rot is reduced when fish meal is applied.


Potatoes prefer a soil which is a little acid. Fish blood and bone meal creates a more alkaline soil. For that reason it is probably not that good to use fish blood and bone meal when planting potatoes. But the amount of alkalinity is very small. In case of doubt use some moss peat or ericaceous compost instead.

BLOOD MEAL FERTILIZER as another ingredient of fish blood and bone meal

Blood meal is a slaughter house  by-product from cattle. It is dried and ends up as a powder. This powder has a high concentration of organic Nitrogen and Iron. Nitrogen is part of the plant cell and chlorophyll. It causes the plant to grow healthy leaves and a healthy root system and as part of chlorophyll it helps the plant to convert sunlight into sugar. These are all good reasons to use fish blood and bone meal fertilizer in the garden.

BONE MEAL FERTILIZER is the third ingredient of fish blood and bone meal

Bone meal is a slow-release fertilizer from ground animal bones and other animal waste products. It provides the soil mainly with phosphorus, calcium and micro-nutrients. Phosphorus is a chemical which is represented by the symbol P. It is an essential element of life and is needed among other things for cell-growth. It also helps with the making of roots and seeds. Phosphorus needs fungi to be broken down and to be passed on to the plants. This is mainly done by Mycorrhiza fungi which penetrates the roots of plants. Bone meal is not soluble in water so it takes a long time to be processed and taken up by the plant roots. You can use bone meal on its own well in advance, for instance when you prepare the soil for next year in autumn, Bone meal completes the perfect combination of fish blood and bone meal fertilizer

Bone meal as Lawn Fertilizer on its own or part of fish blood and bone meal

Both the Phosphorus and Calcium in bone meal strengthen the grass plants, including its root system. It also enriches the soil and is beneficial to soil life. For these reason bone meal is beneficial as lawn fertilizer. Even better is the combination of fish blood and bone meal.

Fish blood and bone meal fertilizer in potting compost

When we use potting compost we can add a little fish blood and bone meal fertilizer, which will slowly release its goodness to the roots of the growing plants.





Compiled by: Gwilym ab Ioan 2015