This disclosure relates to water-absorbing and slow/controlled release fertilizer, in particular to a water-absorbing and water-retaining multi-nutrient biodegradable polymeric slow/controlled release fertilizer having a semi-interpenetrating network structure, and preparation methods thereof. The method can comprises the steps of: reacting formaldehyde with urea to obtain a hydroxymethyl urea solution; adding acrylic acid and acrylamide monomers into another reactor, and adding a KOH solution to adjust the neutralization degree of acrylic acid, then adding one of inorganic clay, pretreated crop straw or cellulose, then adding initiator, monopotassium phosphate and the prepared hydroxymethyl urea solution sequentially; allowing to react at temperature after being mixed uniformly to obtain a viscous product; and granulating the viscous product and oven drying the same to obtain the fertilizer. The fertilizer prepared according to the present invention has strong water-absorbing and water-retaining capacity, and an excellent slow release performance for nitrogen, phosphorus and potassium contained as nutrients.

Novel granular fertilizers and methods of making those fertilizers are provided. The method utilized involves recycling streams, including one that provides water having dissolved solids therein, with that water being used during the mixing and granulation process. This method results in a low-moisture, hard, substantially spherical granule, which can include any number of macronutrients and/or micronutrients. Advantageously, the granular fertilizer can be applied to the soil around plants to supply those plants with the necessary nutrients.

Novel granular fertilizers and methods of making those fertilizers are provided. The method utilized involves recycling streams, including one that provides water having dissolved solids therein, with that water being used during the mixing and granulation process. This method results in a low-moisture, hard, substantially spherical granule, which can include any number of macronutrients and/or micronutrients. Advantageously, the granular fertilizer can be applied to the soil around plants to supply those plants with the necessary nutrients.

Plant fertilizer compositions, products, systems, kits, and methods. Products and methods for increasing the amount of soluble phosphorus in soil, solubilizing or increasing the level of soluble phosphorus and/or bioavailability of phosphorus in soil. Bioactivated fertilizer compositions and related methods for increasing phosphorus solubility and/or bioavailability in soil.

Plant fertilizer compositions, products, systems, kits, and methods. Products and methods for increasing the amount of soluble phosphorus in soil, solubilizing or increasing the level of soluble phosphorus and/or bioavailability of phosphorus in soil. Bioactivated fertilizer compositions and related methods for increasing phosphorus solubility and/or bioavailability in soil.

A potassium humate, rock phosphorous, sulfur granule: a fully soluble potassium humate component comprising about 3% of the composite granule; a sulfur component comprising about 15% of the composite granule; and a rock phosphate powder component comprising about 82% of the composite granule. The composite granule is semi-soluble and has a pH of 2.5 to about 12.

A potassium humate, rock phosphorous, sulfur granule: a fully soluble potassium humate component comprising about 3% of the composite granule; a sulfur component comprising about 15% of the composite granule; and a rock phosphate powder component comprising about 82% of the composite granule. The composite granule is semi-soluble and has a pH of 2.5 to about 12.

A method of processing a powder, comprising (a) contacting the powder with (i) a 2-40% by weight solution of a sulphur- or phosphorous-containing mineral acid or a mixture thereof, or (ii) one or more alkaline earth metal oxides, carbonates or hydroxides, or a mixture thereof; (b) combining the product of (a)(i) with one or more alkaline earth metal oxides, carbonates or hydroxides, or a mixture thereof; or combining the product of (a)(ii) with a 2-40% by weight solution of a sulphur- or phosphorous-containing mineral acid or a mixture thereof and optionally with further of the alkaline earth metal oxides, carbonates or hydroxides, or a mixture thereof; and (c) granulating the combination of (b) to form granules.

Phosphate- and potassium-containing fertilisers are made using the granules.

A method of processing a powder, comprising (a) contacting the powder with (i) a 2-40% by weight solution of a sulphur- or phosphorous-containing mineral acid or a mixture thereof, or (ii) one or more alkaline earth metal oxides, carbonates or hydroxides, or a mixture thereof; (b) combining the product of (a)(i) with one or more alkaline earth metal oxides, carbonates or hydroxides, or a mixture thereof; or combining the product of (a)(ii) with a 2-40% by weight solution of a sulphur- or phosphorous-containing mineral acid or a mixture thereof and optionally with further of the alkaline earth metal oxides, carbonates or hydroxides, or a mixture thereof; and (c) granulating the combination of (b) to form granules.

Phosphate- and potassium-containing fertilisers are made using the granules.

The invention relates to the field of controlled release fertilizer technology, and in particular to a special film-coated controlled release fertilizer for peanut in a high yield field, which comprises an outer layer, an intermediate layer and an inner layer, integrates the ingredients for disease and pest control, chemical control, growth promotion and premature senescence prevention, controls the release period, improves the fertilization efficiency without the need of top application throughout the growth period, saves labor cost, and has positive effects on improving peanut yield and quality.