EM Maize Trial

Excellent Yield Increases in 2015 Maize Trial

This trial was designed to determine the effectiveness of 6 EM treatment variations, against a control on Maize, at Ashcroft Farm at Carew. The yield as evaluated by picking all the cobs over a set distance (10 metres).

Method and Materials

  • History of paddock: ex kale             
  • Plot size and layout: See table 1
  • Maize variety: Pioneer…                   
  • Sowing date:  25/10/14
  • Date of product applications; All products, 2/12/14 and repeated on 3/2/15 (flowering)
  • Trial Design: Treatments= 7,   Replicates= 4   see Table 1
  • Plot Size : 10 metres long by 0.5 metres wide (1 row) equalling, 5 m2,
  • Harvest Date:  20/4/15
  • Harvest Method: 5 metre row lengths were harvested per plot (just cobs).  The plots were harvested as numbered plots, with no reference to treatments (blind approach).
  • Data Analysis: Independent data analysis was carried out by Dr Tim Jenkins


The aim of this trial was to test EM on Maize yield, and in particular compare a number of variations of EM, including some combinations with Nitrogen.

  • EM gave a significant and economic yield response when applied to a Maize Crop
  • EM-RTU, our standard recommended product for this application, was the best performing treatment.
  • The variation of EM, (EMN-RTU) which included some N in the manufacturing process, did not perform better than our standard product EM-RTU.
  • EMN-RTU with a half rate of Nitrogen, performed better than a full rate of Nitrogen not containing EM. 


Yields are expressed as fresh weight.

Ashcroft Farm Maize Trial 2015: Total cob wt per plot.  Effect of EM treatments with and without molasses plus the effect of EM with a half rate of N compared to a full rate.

EM-RTU and EM-RTU plus molasses were similar and both significantly better for yield than the control ( 5%). The inclusion of molasses gave a slight lift when it was added to EM-RTU and EMN-RTU (not significant). Combining EM with a half rate of Nitrogen appeared to be very successful and in fact was better than a full rate of Nitrogen. 

Weakly Significant at 5%, P=0.0508 

Ashcroft Farm Maize Trial 2015: Total cob wt.  Effect of combined EM treatments (not N treatments)   compared to untreated control

When we combine the EM treatments (excluding the Nitrogen treatments) and compare these to the control we find we get a significant increase in yield over control. Overall a very positive result, demonstrating that EM can significantly increase the yield of Maize.

Significant at 5% level, P=0.033

Ashcroft Farm Maize Trial 2015: Total cob wt.  Effect of Nitrogen with, or without EM compared to untreated control (tonnes/ha)

By looking at the Nitrogen treatments in isolation we can see some trends more clearly. Nitrogen did give a slight increase in yield over the untreated control. EM combined with Nitrogen at half rate (23kgN/ha cp 46 kgN/ha) was as good as or slightly better than the high rate of N (46).  We can’t draw conclusions in this particular comparison as; we did not compare all combinations of the N with EM. This comparison needs to be repeated in more detail.


The cost of 2 applications of EM was about $100. The extra yield of Cobs amounted to 1.8 tonnes/ha (cob portion only). The value of maize is 20 cents/kg.  EM increased Cob yield by an extra 1800kg/ha. The value of this extra yield is $360/ha, less cost of input ($100), leaving a profit of $260 per ha. We can assume this yield increase is actually greater than this, as this yield, does not take into account the non-cob parts of the plant, which were not measured in this trial. Therefore the use of EM-RTU on Maize has shown to be a very positive input, with a high margin of economic return. 

For more detailed information download the full trial sheet.