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Carboxy Plus®

Specialty Fertilizer Additive


Product Overview

Carboxy Plus® is a carboxylic acid fertilizer additive developed to improve the availability of phosphate, calcium, iron, magnesium and zinc nutrients to growing plants. This product is a supplement to improve nutrient availability and uptake and improve tolerance to sodium. Adding Carboxy Plus to the seed furrow with starter or pop up fertilizers makes plant nutrients more available and increases tolerance to sodium in saline soils. It is a proprietary composition of 50% nature-based carboxylic acid solution that mimics what is naturally produced by plant root and soil microbes.

*For manufacturing use only

Carboxy Plus logo


  • Helps to convert nutrients to more plant available forms
  • Proprietary composition of 50% carboxylic acid solution
  • Mimics what is naturally produced by plant roots and soil microbes


  • Enhances early seedling vigor in cool soils by increasing phosphate availability
  • Reduces physiological stress from deficiencies in calcium, iron, magnesium and zinc
  • Increases tolerance to physiological stress induced by excess sodium.
  • Aids in micronutrient availability
  • Improves salt tolerance and helps plants overcome salt toxicity

How Does It Work?

Carboxy Plus is a product developed from years of research on plant roots, rhizosphere microorganisms, and mycorrhizal fungi. Soil microorganisms and plant roots secrete compounds that solubilize minerals and make nutrients available to plants. Root secretions from a young seedling starting out in cool soil is not sufficient to support microbial activity in its rhizosphere. Therefore, the seedlings get off to a slow start and often experience early nutritional stress, especially phosphorus deficiency. This product helps to improve the availability of phosphate, calcium, iron, magnesium, and zinc to growing plants by sequestering calcium, magnesium, iron, zinc, and manganese in the presence of phosphate. This helps by releasing potassium and sodium from the clay lattice.

Carboxy Plus works in different ways depending on the soil conditions:

  • In low phosphate soils, Carboxy Plus improves the availability of added phosphate nutrients.
  • In high phosphate soils when the availability of many nutrients is limited, Carboxy Plus added to the seed furrow increases the availability of soil phosphorus and of phosphate-bound calcium, iron, zinc and magnesium.
  • In alkaline and calcareous soils when pH limits nutrient availability, Carboxy Plus improves the availability of calcium, iron, magnesium, zinc and phosphorus.
  • In tropical soils, Carboxy Plus aids the plant in overcoming nutrient deficiency induced by aluminum toxicity.
  • In saline soil, Carboxy Plus reduces plant stress from excess sodium by helping to leach it out of the rootzone.


  • Group 3

    Key crops include, but are not limited to: oranges, edible beans, corn, table grapes, tomatoes  and wheat

  • Farm Plane

    Carboxy Plus can be used during:

    • Planting – in the seed furrow with popup or starter fertilizer
    • Fertigation – in the fertilizer solution
    • Soil injection – in preplant or side dress liquid fertilizer
    • Drip irrigation – in the fertilizer solution
    • Center pivot – in the fertilizer solution
  • Crop Rotation

    Review label for specific application rates and recommendations

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