Fertilizer particle with a coating

Abstract

The present disclosure provides a fertilizer particle comprising a solid core and a continuous coating wherein the continuous coating is at least partially covering the solid core, and the continuous coating comprises from 20 to 90 weight% of a carrier selected from the group consisting of polyhydric alcohols and derivatives thereof, based on the total weight of the continuous coating, and from 102 to 1015 colony-forming units (CFU) / g of at least one bacteria, based on the total weight of the continuous coating. The present disclosure also provides a method for producing a fertilizer particle and the use of a fertilizer particle.

Description

[0001] Fertilizer particle with a coating

[0002] Field of the disclosure

[0003] The present disclosure is related to the field of fertilizers, in particular coated fertilizer particles.

[0004] Background information

[0005] Solid fertilizer particles are widely used today in agriculture. They represent an efficient way to provide nutrients required by plants for optimal growth. Fertilizer particles can comprise a range of elements but usually contain at least one of the macronutrients (nitrogen, phosphorus, and potassium).

[0006] Recently, there has been developments in the field of microbes as agronomic inputs. It has been known for some time that soil microbes play an important role in growing a plant and in soil health. Microbes can have a range of benefits, such as solubilizing phosphorus-containing solids, and nitrogen-fixation from the atmosphere. It has now been found that it can be beneficial for a field to receive microbe-containing inputs.

[0007] It is common to apply a coating composition to fertilizer particles. The coating composition may improve the chemical or physical properties of the particles. However, microbes are very different from traditional agronomic inputs such as fertilizers and crop protection products, which are usually inorganic salts or small organic molecules. As such, they require the development of new techniques to be applied to a field.

[0008] Summary of the disclosure

[0009] In a first aspect, the present disclosure provides a fertilizer particle comprising a solid core comprising one, two, or three elements selected from the group consisting of nitrogen, phosphorus, and potassium, and a single layer of between 0.05 and 0.50 weight% of a continuous coating, wherein: the continuous coating is at least partially covering the solid core, and the single layer of continuous coating comprises: • from 80 to 90 weight% of a carrier selected from the group consisting of polyhydric alcohols chosen out of glycols, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3- butanediol, 1,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5- pentanediol, triols, and derivatives thereof comprising compounds o where one of the hydroxy group has been turned into an ether, an ester, or a carbonate, o in the form of polymers of said polyhydric alcohols chosen out of diethylene glycol, triethylene glycol and any polyethylene glycol, and o derivatives of said polymers chosen out of mono ethers, and diethers of polyethylene glycol chosen out of monomethyl diethylene glycol, monoethyl diethylene glycol, monopropyl diethylene glycol, monobutyl diethylene glycol, dimethyl diethylene glycol, diethyl diethylene glycol, dipropyl diethylene glycol, dibutyl diethylene glycol, and 2-(2-ethoxyethoxy)ethanol, based on the total weight of the continuous coating, and

[0010] • from 102to 1015colony-forming units (CFU) / g of at least one bacteria, based on the total weight of the continuous coating.

[0011] It has been found that microbes can survive for several months in the above mentioned polyhydric alcohols, and in the same compositions applied as coating to fertilizer particles. This greatly facilitates the application of microbes to a field. Bacteria applied to a field can provide a wide range of benefits to the plants growing in the field, i.e. they can absorb nitrogen in the atmosphere and create plant-available nitrogen in the soil, solubilize the phosphorus contained in minerals to make it plant- available, produce complex organic molecules that improve plant health, and / or produce organic molecules with a crop-protection effect (biocide, pesticide).

[0012] A fertilizer particle comprising nutrients and coated with a composition containing a bacteria is a very attractive product because it provides a lot of benefits to the field and the plants growing there, and it also reduces the workload for a farmer by applying these two products in a single operation.

[0013] In another aspect, the present disclosure provides a method for producing a fertilizer particle according to the first aspect, the method comprising: a) mixing from 102to 1015colony-forming units (CFU) / g of at least one bacteria, based on the total weight of the continuous coating, with from 80 to 90 weight% of a carrier selected from the group consisting of polyhydric alcohols chosen out of glycols, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4- pentanediol, 1,5-pentanediol, triols, and derivatives thereof comprising compounds where one of the hydroxy group has been turned into an ether, an ester, or a carbonate, in the form of polymers of said polyhydric alcohols chosen out of diethylene glycol, triethylene glycol and any polyethylene glycol, and derivatives of said polymers chosen out of mono ethers, and diethers of polyethylene glycol chosen out of monomethyl diethylene glycol, monoethyl diethylene glycol, monopropyl diethylene glycol, monobutyl diethylene glycol, dimethyl diethylene glycol, diethyl diethylene glycol, dipropyl diethylene glycol, dibutyl diethylene glycol, and 2-(2- ethoxyethoxy)ethanol, based on the total weight of the continuous coating, thereby obtaining a coating composition; and b) applying between 0.05 and 0.50 weight% of the coating composition obtained in step a) as a single layer onto a solid fertilizer particle comprising a solid core comprising one, two, or three elements selected from the group consisting of nitrogen, phosphorus, and potassium, the continuous coating being applied to the solid core covering at least partially the solid core.

[0014] In another aspect, the present disclosure provides the use of the fertilizer particle according to the first aspect of the present disclosure as a fertilizer.

[0015] Detailed description of the disclosure

[0016] Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included to better appreciate the teaching of the present invention.

[0017] All references cited in this description are hereby deemed to be incorporated in their entirety by way of reference.

[0018] As used herein, the following terms have the following meanings:

[0019] "A", "an", and "the" as used herein refers to both singular and plural referents unless the context clearly dictates otherwise. By way of example, "a compartment" refers to one or more than one compartment.

[0020] "About" as used herein referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of + / -20 % or less, in particular + / - 10 % or less, more in particular + / -5 % or less, even more in particular + / -1 % or less, and still more in particular + / -0.1 % or less of and from the specified value, in so far such variations are appropriate to perform in the disclosed invention. However, it is to be understood that the value to which the modifier "about" refers is itself also specifically disclosed.

[0021] "Comprise", "comprising", and "comprises" and "comprised of" as used herein are synonymous with "include", "including", "includes" or "contain", "containing", "contains" and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known in the art or disclosed therein.

[0022] The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within that range, as well as the recited endpoints.

[0023] The expression "weight percent", "%wt", "wt.%" or "weight%", here and throughout the description unless otherwise defined, refers to the relative weight of the respective component based on the overall weight of the formulation.

[0024] In a first aspect, the present disclosure provides a fertilizer particle comprising a solid core comprising one, two, or three elements selected from the group consisting of nitrogen, phosphorus, and potassium, and a single layer of between 0.05 and 0.50 weight% of a continuous coating, wherein: the continuous coating is at least partially covering the solid core, and the single layer of continuous coating comprises:

[0025] • from 80 to 90 weight% of a carrier selected from the group consisting of polyhydric alcohols chosen out of ethylene glycol (= 1,2-ethanediol), propylene glycol (= 1,2- propanediol), 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2- pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, triols (such as 1,2,3- propanetriol, also named glycerol), and derivatives thereof comprising compounds o where one of the hydroxy group has been turned into an ether, an ester, or a carbonate, o in the form of polymers of said polyhydric alcohols chosen out of diethylene glycol, triethylene glycol and any polyethylene glycol, more in particular with a melting point below 15°C, and o derivatives of said polymers chosen out of mono ethers, and diethers of polyethylene glycol chosen out of monomethyl diethylene glycol, monoethyl diethylene glycol, monopropyl diethylene glycol, monobutyl diethylene glycol, dimethyl diethylene glycol, diethyl diethylene glycol, dipropyl diethylene glycol, dibutyl diethylene glycol, and 2-(2-ethoxyethoxy)ethanol, based on the total weight of the continuous coating, and

[0026] • from 102to 1015colony-forming units (CFU) / g of at least one bacteria, based on the total weight of the continuous coating.

[0027] It is remarked that the carrier may be a single chemical component, but it may also be a mixture of two or more of the polyhydric alcohols and / or derivates thereof as mentioned above. It has been observed that water-based coatings, or coatings comprising above 20 weight% of water, are undesirable as a lot of fertilizer particles are hygroscopic, and the application of water-based coatings onto these decreases the quality of these particles, i.e. lower particle strength which makes them unsuitable for mechanical spreading, increased caking tendency during storage which makes them more difficult to handle.

[0028] It has further been observed that oil-based coatings containing bacteria are not suitable for use on some fertilizer types, for example fully water-soluble grades intended for use in fertigation systems where the insoluble oil can cause blockages in pipes, sprayers, and drippers.

[0029] It has however been found that compositions comprising a liquid carrier according to the present disclosure as mentioned above, and at least one bacteria in the amount as mentioned above, are suitable to be used as coating composition of solid fertilizer particles. The at least one bacteria may be suspended in the solid carrier, or dissolved in a solvent, such as water, or a water-based mixture, and mixed with the liquid carrier to form a solution or an emulsion.

[0030] The carrier may be anhydrous or contain a small amount of water, such as less than 2.0 weight%, less than 1.5 weight%, or less than 1.0 weight%. Water may be undesirable for some applications since it might degrade the fertilizer particle by dissolving some of the nutrients comprised in the fertilizer core, and negatively impacts some physical properties of the particle, such as the particle strength. But anhydrous products may be significantly more expensive than the same product comprising a small amount of water, such as less than 2.0 weight%, and a compromise may be acceptable.

[0031] The bacteria loading may depend on a number of factors, such as the nature of the bacteria, the stability of the bacteria in the continuous coating and / or coated on the fertilizer particle.

[0032] In some embodiments, the continuous coating comprises from 103to 1015CFU / g, from 104to 1015CFU / g, from 107to 1015CFU / g, from 109to 1015CFU / g, from 1011to 1015CFU / g, from 105to 1013CFU / g, from 105to 1011CFU / g, from 105to 109CFU / g, from 107to 1013CFU / g, from 109to 1013CFU / g, from 1011to 1013CFU / g, from 109to 1011CFU / g, of the at least one bacteria, based on the total weight of the continuous coating.

[0033] The carrier may be of high purity, in particular it may be at least 98% pure, more in particular at least 99% pure.

[0034] In some embodiments, the continuous coating may cover at least 50, 60, 70, 80, 90, 95, 96, 97, 98 or 99% of the surface of the core. In some embodiments, the continuous coating may cover 100% of the surface of the fertilizer particle.

[0035] The continuous coating may cover a single region of the surface of the core or two or more regions of the surface of the core. As used herein, the term "continuous coating" indicates that, in the region or in each region where the coating covers the surface of the core, the coating is substantially continuous (e.g. uninterrupted or unbroken, for example at a microscopic scale). Said another way, a continuous coating may be as formed by the application of a liquid coating composition to the surface, whereas for comparison a non-continuous coating may be as formed from the application of a dry particulate coating composition, in which the material remains in particulate form in the resulting coating.

[0036] In some embodiments, the fertilizer particle comprises from 0.05 to 0.35 weight%, more in particular between 0.05 and 0.31 wt.%, of the continuous coating, based on the total weight of the fertilizer particle.

[0037] In some embodiments, the solid core comprises one, two, or three elements selected from the group consisting of nitrogen, phosphorus, and potassium. Nitrogen, phosphorus, and potassium are called macro-nutrients in agriculture. These are the elements that plants require the most (in weight) for optimal growth. These elements are usually naturally present in soils, but not in enough amount to guarantee an optimal yield.

[0038] In some embodiments, the solid core comprises one or more elements selected from the group consisting of magnesium, calcium, sulfur, boron, iron, copper, molybdenum, manganese, zinc, and mixtures thereof.

[0039] In some embodiments, the continuous coating comprises one or more further components selected from the group consisting of a thickener, a colorant, a sugar, a sugar alcohol, a polycarboxylic acid, an anti-foam agent, and a dispersing agent.

[0040] In some embodiments, the continuous coating comprises from 0.1 to 2.0 weight% of a thickener, based on the total weight of the continuous coating. A thickener may be added in the continuous coating to increase the viscosity of the coating composition in order to prevent or reduce sedimentation of the bacteria and to facilitate an even application of the coating composition onto the fertilizer.

[0041] In some embodiments, the thickener is selected from the group consisting of fumed silica, and clays, such as bentonite and sepiolite. It has been found that fumed silica is a suitable thickener for coating compositions according to the present disclosure. Fumed silica is not a biocide, so the bacteria comprised in the continuous coating is not affected by it, and it can increase the viscosity of compositions comprising a polyhydric alcohol or a derivative thereof, such that the composition is easier to handle and spray. In some embodiments, the thickener is fumed silica. In some embodiments, the thickener is bentonite. In some embodiments, the thickener is sepiolite.

[0042] In some embodiments, the continuous coating comprises a sugar, in particular a sugar selected from the group consisting of monosaccharides and disaccharides, more in particular wherein the sugar is selected from the group consisting of glucose, fructose, galactose, sucrose, lactose, maltose, trehalose, cellobiose, chitobiose, and mixtures thereof. In some embodiments, the continuous coating comprises from 1.0 to 10 weight% of the sugar, based on the total weight of the continuous coating. Sugars, such as monosaccharides and disaccharides, are carbon sources for bacteria, so adding a sugar to the continuous coating may allow the bacteria comprised therein to feed on these carbon sources and survive longer in the coating.

[0043] In some embodiments, the continuous coating comprises a sugar alcohol, in particular a sugar alcohol selected from the group consisting of ethylene glycol, glycerol, erythritol, threitol, arabitol, xylitol, ribitol, mannitol, sorbitol, galactitol, fucitol, iditol, inositol, volemitol, isomalt, maltitol, lactitol, maltotriitol, maltotetraitol, polyglycitol, and mixtures thereof.

[0044] In some embodiments, the continuous coating comprises from 1.0 to 10 weight% of the sugar alcohol based on the total weight of the continuous coating.

[0045] Sugar alcohols are carbon sources for bacteria, so adding a sugar alcohol to the continuous coating may allow the bacteria comprised therein to feed on these carbon sources and survive longer in the coating.

[0046] In some embodiments, the continuous coating comprises a carboxylic acid, in particular a polycarboxylic acid, in particular wherein the carboxylic acid is selected from the group consisting of acetic acid, propionic acid, butyric acid, malic acid, valeric acid, malonic acid, succinic acid, glutaric acid, and mixtures thereof.

[0047] In some embodiments, the continuous coating comprises from 1.0 to 10 weight% of the polycarboxylic acid based on the total weight of the continuous coating.

[0048] Polycarboxylic acids are carbon sources for bacteria, so adding a polycarboxylic acid to the continuous coating may allow the bacteria comprised therein to feed on these carbon sources and survive longer in the coating.

[0049] In some embodiments, the carrier is selected from the group consisting of glycerol, propylene glycol, mono-ethylene glycol, polyethylene glycol, 2-(2-ethoxyethoxy)ethanol, and mixtures thereof.

[0050] In some embodiments, the at least one bacteria is selected from the group consisting of grampositive bacteria, and gram-negative bacteria, in particular wherein the at least one bacteria is selected from the group consisting of Bacillus, Rhizobium, Pseuodomonas, Streptomyces, Azobacter, Azospirillum, Paenibacillus, and combinations thereof. Bacteria suitable for use in agriculture are found in a wide range of genus.

[0051] In some embodiments, the at least one bacteria is a Bacillus bacteria, in particular a Bacillus bacteria selected from the group consisting of Bacillus subtilis, Bacillus racemilacticus, Bacillus licheniformis, Bacillus circulens, Bacillus amyloliquefaciens, Bacillus cereus, and Bacillus pumilus.

[0052] In some embodiments, the at least one bacteria is Paenibacillus azotofixans.

[0053] In some embodiments, the at least one bacteria is a Pseuodomonas bacteria, in particular

[0054] Pseudomonas putida. In some embodiments, the at least one bacteria is a Streptomyces bacteria, in particular Streptomyces griseoviridis or Streptoverticillium griseocamium.

[0055] In some embodiments, the continuous coating comprises more than one bacteria species. In some embodiments, the continuous coating comprises two, three, four, five, six, or seven bacteria species. The continuous coating may comprise a mixture of bacteria, either different bacteria species from the same genus, and / or different bacteria species from different genus.

[0056] In some embodiments, the continuous coating comprises water, in particular wherein the continuous coating comprises from 0.1 to 20 weight%, from 0.1 to 10 weight%, from 1.0 to 20 weight%, or from 1.0 to 10 weight% of water based on the total weight of the continuous coating. Some bacteria are only commercially available as aqueous solution, and isolating these bacteria from water is not viable, so the aqueous solution comprising the bacteria is mixed with the other components of the coating before being applied.

[0057] In another aspect, the present disclosure provides a method for producing a fertilizer particle according to the first aspect, the method comprising: a) mixing from 102to 1015colony-forming units (CFU) / g of at least one bacteria, based on the total weight of the continuous coating, with from 80 to 90 weight% of a carrier selected from the group consisting of polyhydric alcohols chosen out of glycols, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4- pentanediol, 1,5-pentanediol, triols, and derivatives thereof comprising compounds where one of the hydroxy group has been turned into an ether, an ester, or a carbonate, in the form of polymers of said polyhydric alcohols chosen out of diethylene glycol, triethylene glycol and any polyethylene glycol, and derivatives of said polymers chosen out of mono ethers, and diethers of polyethylene glycol chosen out of monomethyl diethylene glycol, monoethyl diethylene glycol, monopropyl diethylene glycol, monobutyl diethylene glycol, dimethyl diethylene glycol, diethyl diethylene glycol, dipropyl diethylene glycol, dibutyl diethylene glycol, and 2-(2- ethoxyethoxy)ethanol, based on the total weight of the continuous coating, thereby obtaining a coating composition; and b) applying between 0.05 and 0.50 wt.% of the coating composition obtained in step a) as a single layer onto a solid fertilizer particle comprising a solid core comprising one, two, or three elements selected from the group consisting of nitrogen, phosphorus, and potassium, the continuous coating being applied to the solid core covering at least partially the solid core. In some embodiments, in step b) between 0.05 to 0.35 weight%, more in particular between 0.05 and 0.31 wt.%, of the continuous coating, based on the total weight of the fertilizer particle, is applied onto the solid core.

[0058] In some embodiments, in step a), one or more components selected from the group consisting of a sugar, a sugar alcohol, a polycarboxylic acid, a colorant, an anti-foam agent, and a dispersing agent are additionally mixed.

[0059] In some embodiments, in step a), additionally a thickener, in particular from 0.1 to 2.0 weight% of the thickener, more in particular fumed silica, based on the total weight of the continuous coating, is mixed.

[0060] In some embodiments, at least one bacteria in step a) is selected from the group consisting of gram-positive bacteria, and gram-negative bacteria, in particular wherein the at least one bacteria is selected from the group consisting of Bacillus, Pseuodomonas, Streptomyces, Rhizobium, Azobacter, Azospirillum, Paenibacillus, and combinations thereof.

[0061] In some embodiments, in step a), water, in particular from 0.1 to 20.0 weight% of water based on the total weight of the continuous coating, is mixed.

[0062] In another aspect, the present disclosure provides the use of the fertilizer particle according to the first aspect of the present disclosure as a fertilizer.

[0063] In another aspect, the present disclosure provides a method of fertilizing a soil or a crop, comprising applying fertilizer particles according to the first aspect of the invention to the soil or the crop.

[0064] Example 1

[0065] A liquid composition comprising 2.5 x 107CFU of Bacillus circulens, Bacillus licheniformis, Bacillus subtilis, and Paenibacillus azotofixans, 90 weight% of propylene glycol, and 1 weight% of fumed silica was prepared. The liquid composition was applied at a rate of 1.5 or 3.0 liters per metric ton of solid fertilizer particles from four different fertilizer products: a 16-16-16 NPK, a 4-28-8 NPK, MOP (potassium sulfate), and a 21-0-0 CAN containing 7.5 weight% of magnesium (see table 1). Uncoated fertilizer particles were used as control.

[0066] Table 1

[0067] The coated particles were sent to a laboratory for analysis and the particles were analyzed for bacterial content at arrival date (t = 0, about 7 days after coating), 31 days after arrival and 59 days after arrival.

[0068] The results are summarized in Table 2. Table 2

[0069] Example 2

[0070] A liquid composition comprising 1 weight% of fumed silica and 10 weight% of a microbial mixture comprising Bacillus pumilus, Bacillus amyloliquefaciens, and two Bacillus subtilis strains, in propylene glycol was prepared. The liquid composition comprises 7.5 x 107CFU / g. A comparative example comprising 1 weight% of fumed silica and 99 weight% of propylene glycol was also prepared. NPK fertilizer (16-16-16) particles were coated with different compositions: the same pure, dry microbial mixture comprising Bacillus pumilus, Bacillus amyloliquefaciens, and two Bacillus subtilis strains used above, the composition comprising fumed silica in propylene glycol, the composition comprising fumed silica and bacteria in propylene glycol. Some particles were left uncoated, the samples are summarized in table 3.

[0071] Table 3

[0072] The particles were sent to a laboratory for analysis and the particles were analyzed for bacterial content at arrival date (t = 0, about 7 days after coating), 30 days after arrival and 60 days after arrival.

[0073] The results are summarized in Table 4. Table 4

[0074] From the results, it can be seen that the bacteria are still viable after at least 60 days in the coating composition.

Claims

Claims1. A fertilizer particle comprising a solid core comprising one, two, or three elements selected from the group consisting of nitrogen, phosphorus, and potassium, and a single layer of between 0.05 and 0.50 weight% of a continuous coating, wherein: the continuous coating is at least partially covering the solid core, and the single layer of continuous coating comprises:• from 80 to 90 weight% of a carrier selected from the group consisting of polyhydric alcohols chosen out of ethylene glycol, propylene glycol, 1,3-propanediol, 1,2- butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4- pentanediol, 1,5-pentanediol, triols, and derivatives thereof comprising compounds o where one of the hydroxy group has been turned into an ether, an ester, or a carbonate, o in the form of polymers of said polyhydric alcohols chosen out of diethylene glycol, triethylene glycol and any polyethylene glycol, and o derivatives of said polymers chosen out of mono ethers, and diethers of polyethylene glycol chosen out of monomethyl diethylene glycol, monoethyl diethylene glycol, monopropyl diethylene glycol, monobutyl diethylene glycol, dimethyl diethylene glycol, diethyl diethylene glycol, dipropyl diethylene glycol, dibutyl diethylene glycol, and 2-(2-ethoxyethoxy)ethanol, based on the total weight of the continuous coating, and• from 102to 1015colony-forming units (CFU) / g of at least one bacteria, based on the total weight of the continuous coating.

2. The fertilizer particle according to claim 1, wherein the fertilizer particle comprises from 0.05 to 0.35 weight%, more in particular between 0.05 and 0.31 weight%, of the continuous coating, based on the total weight of the fertilizer particle.

3. The fertilizer particle according to claim 1 or 2, wherein the continuous coating further comprises one or more components selected from the group consisting of a sugar, a sugar alcohol, a polycarboxylic acid, a colorant, an anti-foam agent, and a dispersing agent.

4. The fertilizer particle according to any one of claims 1 to 3, wherein the continuous coating comprises a thickener, in particular from 0.1 to 2.0 weight% of the thickener, more in particular fumed silica, based on the total weight of the continuous coating.

5. The fertilizer particle according to any one of claims 1 to 4, wherein the bacteria is selected from the group consisting of gram-positive bacteria, and gram-negative bacteria, in particular wherein the at least one bacteria is selected from the group consisting of Bacillus, Pseuodomonas, Streptomyces, Rhizobium, Azobacter, Azospirillum, Paenibacillus, and combinations thereof.

6. The fertilizer particle according to any one of claims 1 to 5, wherein the continuous coating comprises water, in particular wherein the continuous coating comprises from 0.1 to 20 weight% of water based on the total weight of the continuous coating.

7. A method for producing a fertilizer particle according to any one of claims 1 to 6, the method comprising: a) mixing from 102to 1015colony-forming units (CFU) / g of at least one bacteria, based on the total weight of the continuous coating, with from 80 to 90 weight% of a carrier selected from the group consisting of polyhydric alcohols chosen out of ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2- pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, triols, and derivatives thereof comprising compounds where one of the hydroxy group has been turned into an ether, an ester, or a carbonate, in the form of polymers of said polyhydric alcohols chosen out of diethylene glycol, triethylene glycol and any polyethylene glycol, and derivatives of said polymers chosen out of mono ethers, and diethers of polyethylene glycol chosen out of monomethyl diethylene glycol, monoethyl diethylene glycol, monopropyl diethylene glycol, monobutyl diethylene glycol, dimethyl diethylene glycol, diethyl diethylene glycol, dipropyl diethylene glycol, dibutyl diethylene glycol, and 2-(2-ethoxyethoxy)ethanol, based on the total weight of the continuous coating, thereby obtaining a coating composition; andb) applying between 0.05 and 0.50 weight% of the coating composition obtained in step a) as a single layer onto a solid fertilizer particle comprising a solid core comprising one, two, or three elements selected from the group consisting of nitrogen, phosphorus, and potassium, the continuous coating being applied to the solid core covering at least partially the solid core.

8. Method according to claim 7, wherein in step b) between 0.05 to 0.35 weight%, more in particular between 0.05 and 0.31 weight%, of the continuous coating, based on the total weight of the fertilizer particle, is applied onto the solid core.

9. Method according to claim 7 or 8, wherein in step a), one or more components selected from the group consisting of a sugar, a sugar alcohol, a polycarboxylic acid, a colorant, an anti-foam agent, and a dispersing agent are additionally mixed.

10. Method according to any one of claims 7 to 9, wherein in step a), additionally a thickener, in particular from 0.1 to 2.0 weight% of the thickener, more in particular fumed silica, based on the total weight of the continuous coating, is mixed.

11. Method according to any one of claims 7 to 10, wherein the at least one bacteria in step a) is selected from the group consisting of gram-positive bacteria, and gram-negative bacteria, in particular wherein the at least one bacteria is selected from the group consisting of Bacillus, Pseuodomonas, Streptomyces, Rhizobium, Azobacter, Azospirillum, Paenibacillus, and combinations thereof.

12. Method according to any one of claims 7 to 11, wherein in step a), water, in particular from 0.1 to 20.0 weight% of water based on the total weight of the continuous coating, is mixed.

13. Use of a fertilizer particle according to any one of claims 1 to 6 as a fertilizer.

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