{
  "url": "https://openlegislation.uk/fertilisers-regulations-1990/schedule-1/crossheading-compound-fertilisers",
  "json_url": "https://openlegislation.uk/fertilisers-regulations-1990/schedule-1/crossheading-compound-fertilisers.json",
  "legislation": "uksi/1990/887",
  "legislation_title": "The Fertilisers Regulations 1990",
  "legislation_url": "https://openlegislation.uk/fertilisers-regulations-1990",
  "path": "schedule/1/crossheading/compound-fertilisers",
  "kind": "crossheading",
  "number": "SECTION B.",
  "heading": "COMPOUND FERTILISERS",
  "text": "Group\nName of Material\nMeaning\nDeclarations\nLimits of variation (absolute value in percentage by weight, except where otherwise specified)\n(1)\n(2)\n(3)\n(4)\n(5)\n(6)\n*As determined by the Petermann method.\n1\nNPK Fertilisers\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N).\n2 Not less than 5% phosphorus pentoxide (P2O5);\n3 Not less than 5% potassium oxide (K2O).\nThe sum of the three nutrients must be not less than 20% by weight. The product must not contain basic slag, Thomas phosphate, Thomas slag, calcined phosphate, aluminium-calcium phosphate, soft ground rock phosphate, or partially solubilised rock phosphate.\nThe P2O5 content soluble only in mineral acids must not exceed 2%.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nWhere phosphorus pentoxide soluble in water is less than 2% amount of:—\n1 Phosphorus pentoxide soluble in neutral ammonium citrate.\nWhere phosphorus pentoxide soluble in water is equal to or greater than 2% amount of:—\n1 Phosphorus pentoxide soluble in neutral ammonium citrate and in water.\nP2O5 1.1\nP2O5 0.5\n2 Phosphorus pentoxide soluble in water.\nAs set out in paragraph 7(a) of this Schedule\nPotassium oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n+P2O5\n} 1.9\n+K2\n}\nK2O 0.5\nOptical declaration\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\nN 1.1\nN 0.5\nNPK fertiliser containing aluminium-calcium phosphate\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N).\n2 Not less than 57percnt; phosphorus pentoxide (P2O5) of which at least 2% must be soluble in water, and at least 5% soluble in mineral acids; and\n3 Not less than 5% potassium oxide (K2O).\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\nAs set out in paragraph 7 of this Schedule\nThe sum of the three nutrients must be not less than 20% by weight. At least 75% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in alkaline ammonium citrate (Joulie). The product must not contain basic slag, Thomas Phosphate, Thomas slag, calcined phosphate, soft ground rock phosphate or partially solubilised rock phosphate, and not less than 90% of the aluminium-calcium phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 cyanamide nitrogen\n4 ureic nitrogen\nP2O5 1.1\nP2O5 0.5\nPhosphorus Pentoxide (P2P5)\nAmount of phosphorus pentoxide soluble in mineral acids.\nAmount of phosphorus pentroxide soluble in water.\nAmount of phosphorus pentoxide soluble in mineral acids (after deduction of the amount of phosphorus pentoxide soluble in water).\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate.\nAs set out in paragraph 7(a)of this Schedule\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n+P2O5\n} 1.9\n+K2O\n}\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nCl 0.2\nNPK fertiliser containing soft ground rock phosphate\nNPK fertiliser containing partially solubilised rock phosphate\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N).\n2 Not less than 5% phosphorus pentoxide (P2O5) of which at least 2% should be soluble only in mineral acids, at least 5% soluble in neutral ammonium citrate and in water and at least 2.5% soluble in water;\n3 Not less than 5% potassium oxide (K2O).\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nThe sum of the three nutrients must be not less than 20% by weight. Neither product must contain basic slag, Thomas phosphate, Thomas slag, calcined phosphate or aluminium-calcium phosphate. Not less than 90% of the soft ground rock phosphate should be able to pass through a sieve with a mesh of 0.063mm, and not less than 90% of the partially solubilised rock phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nPhosphorus Pentoxide P2O5\nAmount of phosphorus pentoxide soluble in mineral acids.\nAmount of phosphorus pentoxide soluble in water.\nAmount of phosphorus pentoxide soluble in neutral ammonium citrate and in water.\nAmount of phosphorus pentoxide soluble only in mineral acids.\nP2O5 1.1\nAs set out in paragraph 7(a) of this Schedule\nP2P5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n+P2O5\n} 1.9\n+K2O\n}\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nCl 0.2\nNPK fertiliser (Phosphate ingredient, aluminium-calcium phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N);\n2 Not less than 5% phosphorus pentoxide (P2O5);\n3 Not less than 5% potassium oxide (K2O).\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nThe sum of the three nutrients must be not less than 20% by weight. At least 75% of the declared phosphorus pentoxide soluble in alkaline ammonium citrate (Joulie). The product must not contain any phosphate material other than aluminium-calcium phosphate and not less than 90% of the aluminium-calcium phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in mineral acids.\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate.\nP2O5 1.1\nAs set out in paragraph 7(a) of this Schedule\nP2O5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n+P2O5\n} 1.9\n+K2O\n}\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nCl 0.2\nNPK fertiliser (Phosphate ingredient; calcined phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N).\n2 Not less than 5% phosphorus pentoxide (P2O5);\n3 Not less than 5% potassium oxide (K2O).\nThe sum of the three nutrients must be not less than 20 % by weight. The product must not contain any phosphate material other than calcined phosphate. Not less than 75 % of the calcined phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount, where equal to or greater than 1% by weight of:—\nAmount, where equal to or greater than 1% by weight, of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate*\nP2O5 1.1\nP2O5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n+P2O5\n} 1.9\n+K2O\n}\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nCl 0.2\nNPK fertiliser (Phosphate ingredient; soft ground rock phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N).\n2 Not less than 5% phosphorus pentoxide (P2O5);\n3 Not less than 5% potassium oxide (K2O).\nThe sum of the three nutrients must be not less than 20% by weight. At least 55% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in 2% formic acid. The product must not contain any phosphate material other than soft ground rock phosphate. Not less than 90% of the soft ground rock phosphate should be able to pass through a sieve with a mesh of 0.063 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in mineral acids.\nAmount of phosphorus pentoxide soluble in 2% formic acid.\nP2O5 1.1\nAs set out in paragraph 7(a) of this Schedule\nP2O5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n+P2O5\n} 1.9\n+K2O\n}\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nCl 0.2\nNPK fertiliser (Phosphate ingredient: basic slag only)\nNPK fertiliser (Phosphate ingredient: Thomas phosphate only)\nNPK fertiliser (Phosphate ingredient: Thomas slag only\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 not less than 3% nitrogen (N).\n2 not less than 5% potassium oxide (K2O).\n3 not less than 5% potassium oxide (K2O).\nThe sum of the three nutrients must be not less than 20% by weight. The product must not contain any phosphate material other than basic slag, Thomas phosphate or Thomas slag.\nNot less than 75% of the basic slag, Thomas phosphate or Thomas slag should be able to pass through a sieve with a mesh of 0.160 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in 2% citric acid.\nP2O5 1.1\nP2O5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n+P2O5\n} 1.9\n+K2O\n}\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nCl 0.2\nNP Fertiliser\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N);\n2 Not less than 5% phosphorus pentoxide (P2O5).\nThe sum of the two nutrients must be not less than 18% by weight. The product must not contain basic slag, Thomas phosphate, Thomas slag, calcined phosphate, aluminium-calcium phosphate, soft ground rock phosphate or partially solubilised rock phosphate.\nThe P2O5 content soluble only in mineral acids must not exceed 2%.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nWhere phosphorus pentoxide soluble in water is less than 2% amount of:—\n1 Phosphorus pentoxide soluble in neutral ammonium citrate.\nWhere phosphorus pentoxide soluble in water is equal to or greater than 2%, amount of:—\n1 Phosphorus pentoxide soluble in neutral ammonium citrate and in water.\nP2O5 1.1\nAs set out in paragraph 7(a) of this Schedule\nP2O5 0.5\n2 Phosphorus pentoxide soluble in water.\nN\n}\n+P2O5\n} 1.5\n2\nNP fertiliser containing aluminium-calcium phosphate\nProduct obtained chemically or by blending without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N);\n2 Not less than 5% phosphorus pentoxide (P2O5) of which at least 2% must be soluble in water, and at least 5% soluble in mineral acids.\nThe sum of the two nutrients must be not less than 18% by weight. At least 75% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in alkaline ammonium citrate (Joulie). The product must not contain basic slag, Thomas phosphate, Thomas slag, calcined phosphate, soft ground rock phosphate or partially solubilised rock phosphate, and not less than 90% of the aluminium-calcium phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in mineral acids.\nAmount of phosphorus pentoxide soluble in water.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in mineral acids (after deduction of the amount of phosphorus pentoxide soluble in water).\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate.\nAs set out in paragraph 7(a) of this schedule\nN\n}\n+P2O5\n} 1.5\nNP fertiliser containing soft ground rock phosphate\nNP fertiliser containing partially solubilised rock phosphate\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:\n1 not less than 3% nitrogen (N);\n2 not less than 5% phosphorus pentoxide (P2O5) of which at least 2% should be soluble only in mineral acids, at least 5% soluble in neutral ammonium citrate and in water and at least 2.5% soluble in water.\nThe sum of the two nutrients must be not less than 18% by weight. Neither product must contain basic slag, Thomas phosphate, Thomas slag, calcined phosphate or aluminium-calcium phosphate. Not less than 90% of the soft ground rock phosphate should be able to pass through a sieve with a mesh of 0.063 mm, and not less than 90% of the partially solubilised rock phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in mineral acids.\nAmount of phosphorus pentoxide soluble in water.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in neutral ammonium citrate and in water.\nAmount of phosphorus pentoxide soluble only in mineral acids.\nAs set out in paragraph 7(a) of this Schedule\nN\n}\n+P2O5\n} 1.5\nNP fertiliser (Phosphate ingredient: aluminium-calcium phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N);\n2 Not less than 5% phosphorus pentoxide (P2O5).\nThe sum of the two nutrients must be not less than 18% by weight. At least 75% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in alkaline ammonium citrate (Joulie). The product must not contain any phosphate material other than aluminium-calcium phosphate and not less than 90% of the aluminium-calcium phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in mineral acids.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate.\nAs set out in paragraph 7(a) of this Schedule\nN\n}\n+P2O5\n} 1.5\nNP fertiliser (Phosphate ingredient: calcined phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N);\n2 Not less than 5% phosphorus pentoxide (P2O5).\nThe sum of the two nutrients must be not less than 18% by weight. The product must not contain any phosphate material other than calcined phosphate. Not less than 75% of the calcined phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate*.\nP2O5 1.1\nN\n}\n+P2O5\n} 1.5\nP2O5 0.5\nNP fertiliser (Phosphate ingredient: soft ground rock phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N);\n2 Not less than 5% phosphorus pentoxide (P2O5).\nThe sum of the two nutrients must be not less than 18% by weight. At least 55% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in 2% formic acid. The product must not contain any phosphate material other than soft ground rock phosphate. Not less than 90% of the soft ground rock phosphate should be able to pass through a sieve with a mesh of 0.063 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in mineral acids.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in 2% formic acid.\nAs set out in paragraph 7 of this Schedule\nN\n}\n+P2O5\n} 1.5\nNP fertiliser (Phosphate ingredient: basic slag only)\nNP fertiliser (Phosphate ingredient: Thomas Phosphate only)\nNP fertiliser (Phosphate ingredient: Thomas slag only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N).\n2 Not less than 5% phosphorus pentoxide (P2O5).\nThe sum of the two nutrients must be not less than 18% by weight. The product must not contain any phosphate material other than basic slag, Thomas phosphate or Thomas slag. Not less than 75% of the basic slag, Thomas phosphate or Thomas slag should be able to pass through a sieve with a mesh of 0.160 mm.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPhosphorus Pentoxide (P2O5)\nAmount of phosphorus pentoxide soluble in 2% citric acid.\nP2O5 1.1\nN\n}\n+P2O5\n} 1.5\nP2O5 0.5\n3\nNK fertiliser\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 3% nitrogen (N).\n2 Not less than 5% potassium oxide (K2O).\nThe sum of the two nutrients must be not less than 18% by weight.\nNitrogen (N)\nEEC fertiliser\nOther than EEC fertilisers\nAmount of total nitrogen.\nAmount, where equal to or greater than 1% by weight of:—\nAmount of total nitrogen.\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\n1 nitric nitrogen\n2 ammoniacal nitrogen\n3 ureic nitrogen\n4 cyanamide nitrogen\nN 1.1\nAs set out in paragraph 7 of this Schedule\nN 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nN\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations.\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\n4\nPK fertiliser\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 5% phosphorus pentoxide (P2O5);\n2 Not less than 5% potassium oxide (K2O).\nThe sum of the two nutrients must be not less than 18% by weight. The product must not contain basic slag, Thomas phosphate, Thomas slag, calcined phosphate, aluminium-calcium phosphate, soft ground rock phosphate, or partially solubilised rock phosphate.\nThe P2O5 content soluble only in mineral acids must not exceed 2%.\nPhosphorus Pentoxide (P2O5)\nWhere phosphorus pentoxide soluble in water is less than 2% amount of:—\n1 Phosphorus pentoxide soluble in neutral ammonium citrate.\nWhere phosphorus pentoxide soluble in water is equal to or greater than 2%,amount of:—\n1 Phosphorus pentoxide soluble in neutral ammonium citrate and in water.\n2 Phosphorus pentoxide soluble in water.\nP2Ot 1.1\nAs set out in paragraph 7(a) of this Schedule.\nP2O5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nP2O5\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in Chlorine” may be made.\nC1 0.2\nPK fertiliser containing aluminium-calcium phosphate\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 5% phosphorus pentoxide (P2O5) of which at least 2% must be soluble in water, and at least 5% soluble in mineral acids.\n2 Not less than 5% potassium oxide (K2O).\nThe sum of the two nutrients must be not less than 18% by weight. At least 75% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in alkaline ammonium citrate (Joulie). The product must not contain basic slag, calcined phosphate, soft ground rock phosphate, or partially solubilised rock phosphate, and not less than 90% of the aluminium-calcium phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nPhosphorus Pentoxide (P2O)\nAmount of phosphorus pentoxide soluble in mineral acids.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in water.\nAmount of phosphorus pentoxide soluble in mineral acids (after deduction of the amount of phosphorus pentoxide soluble in water).\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate.\nAs set out in paragraph 7(a) of this Schedule\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nP2O5\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\nPK fertiliser containing soft ground rock phosphate\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 5% phosphorus pentoxide (P2O5) of which at least 2% should be soluble only in mineral acids, at least 5% soluble in neutral ammonium citrate and in water and at least 2.5% soluble in water.\n2 Not less than 5% potassium oxide (K2O).\nPhosphorus Pentoxide (P2O)\nAmount of phosphorus pentoxide soluble in mineral acids.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in water.\nAmount of phosphorus pentoxide soluble in neutral ammonium citrate and water.\nAmount of phosphorus pentoxide soluble only in mineral acids.\nAs set out in paragraph 7(a) of this Schedule\nPK fertiliser containing partially solubilised rock phosphate\nThe sum of the two nutrients must be not less than 18% by weight. Neither product must contain basic slag, Thomas phosphate, Thomas slag, calcined phosphate or aluminium-calcium phosphate. Not less than 90% of the soft ground rock phosphate should be able to pass through a sieve with a mesh of 0.063 mm, and not less than 90% of the partially solubilised rock phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nP2O5\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\nPK fertiliser (Phosphate ingredient: aluminium-calcium phosphate only)\nProduct obtained chemically by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 5% phosphorus pentoxide (P2O5).\n2 Not less than 5% potassium oxide (K2O5).\nThe sum of the two nutrients must be not less than 18% by weight. At least 75% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in alkaline ammonium citrate (Joulie). The product must not contain any phosphate material other than aluminium-calcium phosphate and not less than 90% of the aluminium-calcium phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nPhosphorus Pentoxide (P2O)\nAmount of phosphorus pentoxide soluble in mineral acids.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate.\nAs set out in paragraph 7(a) of this Schedule\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nP2O5\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\nPK fertiliser (Phosphate ingredient: calcined phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 5% phosphorus pentoxide (P2O5);\n2 Not less than 5% potassium oxide (K2O).\nThe sum of the two nutrients must be not less than 18% by weight. The product must not contain any phosphate material other than calcined phosphate. Not less than 75% of the calcined phosphate should be able to pass through a sieve with a mesh of 0.160 mm.\nPhosphorus Pentoxide (P2O)\nAmount of phosphorus pentoxide soluble in alkaline ammonium citrate*.\nP2O5 1.1\nP2O5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nP2O5\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\nPK fertiliser (Phosphate ingredient: soft ground rock phosphate only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 5% phosphorus pentoxide (P2O5);\n2 Not less than 5% potassium oxide (K2O).\nThe sum of the two nutrients must be not less than 18% by weight. At least 55% of the declared phosphorus pentoxide soluble in mineral acids must be soluble in 2% formic acid. The product must not contain any phosphate material other than soft ground rock phosphate. Not less than 90% of the soft ground rock phosphate should be able to pass through a sieve with a mesh of 0.063 mm.\nPhosphorus Pentoxide (P2O)\nAmount of phosphorus pentoxide soluble in mineral acids.\nP2O5 1.1\nP2O5 0.5\nAmount of phosphorus pentoxide soluble in 2% formic acid.\nAs set out in paragraph 7(a) of this Schedule.\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nP2O5\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\nPK fertiliser (Phosphate ingredient: basic slag only)\nPK fertiliser (Phosphate ingredient: Thomas phosphate only)\nPK fertiliser (Phosphate ingredient: Thomas slag only)\nProduct obtained chemically or by blending, without addition of organic nutrients of animal or vegetable origin, containing by weight:—\n1 Not less than 5% phosphorus pentoxide (P2O5);\n2 Not less than 5% potassium oxide (K2O).\nThe sum of the two nutrients must be not less than 18% by weight. The product must not contain any phosphate material other than basic slag. Thomas phosphate or Thomas slag. Not less than 75% of the basic slag, Thomas phosphate or Thomas slag should be able to pass through a sieve with a mesh of 0.160 mm.\nPhosphorus Pentoxide (P2O)\nAmount of phosphorus pentoxide soluble in 2% citric acid.\nP2O5 1.1\nP2O5 0.5\nPotassium Oxide (K2O)\nAmount of potassium oxide soluble in water.\nK2O 1.1\nP2O5\n}\n++K2O\n} 1.5\nK2O 0.5\nOptional declarations\nAmount of chlorine.\nWhere the chlorine content is not greater than 2% the statement “low in chlorine” may be made.\nC1 0.2\n5\nCompound fertiliser\nProducts not otherwise specified in Groups 1 to 4 of Section B of this table, obtained by mixing materials which together will provide two or more of the main nutrients nitrogen (N), phosphorus pentoxide (P2O5) and potassium oxide (K2O), but excluding materials used for improving soil structure or as growing media and which contain less than 1% each of these nutrients. At least one of the nutrients must be derived from a material mentioned in the second column of Section A of the table.\nNitrogen (N)\nAmount of total nitrogen.\nN\n0.5 (for declarations below 3.5% N)\n1.1 (for declarations 3.5% and above)\nAmount of ureic nitrogen save that a declaration of 10% or less need not be made.\nAs set out in paragraph 7(b) of this Schedule.\nPhosphorus Pentoxide (P2O5)\nAmount of total phosphorus pentoxide.\n(for declarations below 5.5% P2O5) and above)\nAmount of phosphorus pentoxide soluble in water.\nAmount of phosphorus pentoxide insoluble in water.\n(for declarations below 5.5% P2P5)\nAs set out in paragraph 7(a) of this Schedule\nK2O\n0.5 (for declarations below 5.5% K2O)\n1.1 (for declarations 5.5% K2O and above)\nPotassium Oxide K2O)\nAmount of total potassium oxide.\nN+P2O5\n1.5\nN+K2O\n1.5\nP2O5+K2O\n1.5\nN }\n+P2O5 }\n1.9\n+K2O",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1990/887/schedule/1/crossheading/compound-fertilisers",
    "retrieved_at": "2026-10-29T15:21:24.289770+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}