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Calcium is a primary constituent of all cell walls and membranes. Restrictions in the availability of calcium will adversely affect cell division, impair the structural stability and the permeability of cell walls. Increasing fruit calcium promotes longer storage life and resists a range of physiological break down conditions including water core, bitterpit and internal browning.


Omex CalMax is a fully water soluble fluid emulsion 10-0-3 product containing 11.0% calcium and a balanced range of micro elements. Omex CalMax is specifically formulated for use as a foliar fertilizer and can be applied to all fruit and vegetable crops to improve fruit firmness, storability, colour and skin finish.

pH (10% solution): 5.5-6.5, Specific Gravity: 1.50 @ 18ºC

Tank Mixing Compatibility

Omex CalMax is compatible with most, but not all, pesticides, growth regulators and micro-nutrients with regard to physical tank mixing and biological effects on the crop. However, Omex cannot accept liability for any loss or damage as not all pesticides have been tested and because the efficacy of any mix will depend on, among other factors, the pesticide concerned, crop conditions, growth stage, weather and volumes of water used.

CalMax Treated

Application Guidelines

  • Apply CalMax Complete 3 times per season, beginning at tuber initiation.
  • Subsequent applications should be on 10-14 day intervals.
  • Application rate: 1.0 L CalMax and 0.6 L uPtaKe/ac.
  • Order of addition to sprayer is (1)water, (2)CalMax Complete and (3)pesticide.

Directions for Use

  • The spray tank should be filled with half of the required amount of water (recommended water rate is 500-1500 litres per hectare).
  • After shaking the container, measure the required amount of Omex CalMax.
  • Always shake container before opening and add to the tank whilst maintaining constant agitation. Add remaining water to correct dilution.
  • Spray.


Calcium Grow Out Trial…

  • All tubers from the 1999 CalMax trials (treated and check) were planted in 2000.
  • Objective was to determine if calcium could improve plant vigor and yield / quality on the following crop.
  • Tubers from 20 different trials were planted out (40 plots). 20’ rows, spaced 12” on center.
  • Each plot was hand harvested, weighed and graded.


  • Significant effect on the Russet Burbank (7/8 trials): size shift and yield
  • No net effect on the Shepody
  • Effect on fresh market (red) potatoes: (236 vs. 264 cwt/ac)
  • Significant yield differences between seed stocks



Check - Russets
Check - Russets


Potatoes - Check
Potatoes - Treated
Potatoes - Check
Potatoes - Treated


Check - Russets
CalMax G2 - Russets
Potatoes - Check
Potatoes - CalMax G2

Potato yield harvested in untreated vs. treated with CalMax G2 fields
Potato yield by weight category harvested in untreated vs. treated with CalMax G2 fields
Numbers of potato tubers harvested in untreated vs. treated with CalMax G2 fields
Number of potato tubers by weight category harvested in untreated vs. treated with CalMax G2 fields