Agrizest: Here is The Evidence


The developer and manufacturers of Agrizest are happy to answer questions about the product.

They have heard it all:

  • It is not Western science” – the inventor was awarded his MSc with Honours at Massey University and has a further 36 years in NZ carrying out R&D. Zest Biotech’s technologies are based on science that has been published at the highest levels internationally including for the United Nations; there is a large body of scientific papers from highly qualified scientists available 

  • Agrizest has not been peer reviewed” –the science was reviewed for the inventors’ selection for the World Technology Awards and similarly by colleagues in the biotechnology sector in NZ. The technology has also been presented at multiple international conferences as well as conferences here in New Zealand. Zest Biotech is always open to further peer reviews if necessary.

  • “It’s nothing but another seaweed product (even “snake oil”)– Agrizest contains seaweed, but at a level of less than 10%. The proprietary formulae for Zest Biotech products, including Agrizest, are based on biological combinations of natural plant-based ingredients that provide crop (horticulture and pasture) stimulation for better plant health. For the science minded, elicitation of phenylpropanoid cascades are the likely mechanism of action and molecular pattern recognition receptor signalling is the mode of action of Agrizest

  • “What about Zespri or KVH spray calendars” Agrizest and Primazest can be used on kiwifruit orchards as they are listed by Zespri as Allowed Other Compounds (AOC). Agrizest and Primazest are authorised by MPI (under the ACVM Act 1997) as exempt from registration and can be use on all crops pre and post flowering no withholding period.
    Both products can legitimately be recorded on kiwifruit growers’ spray diaries. All of Zest Biotech’s products are certified by BioGro for use in organic production.

  • “If it is so good, why isn’t it on the promoted spray calendars?” The answer probably lies in both profit margins and the way R&D works in NZ

  • Oh I am waiting for the yeast based biological stuff the (Zespri funded) scientists are developing” – anything with yeast in it is poles apart from Agrizest. The yeast approach is to kill things. Agrizest doesn’t kill anything- it makes plants healthier by stimulating the plant’s own immune system.

Agrizest has undergone extensive trials over several years.  

There is large body of data that shows while Agrizest is not designed to kill Psa (or kill anything for that matter) it does stimulate the kiwifruit vine immune system and improve plant health.

Healthy plant = healthy fruit = high orchard gate returns.

For interested growers, here is a data set from 2016 and 2017 pertaining to G3:

Comparison of fruit quality from Agrizest® treated orchards (in which copper is applied judiciously) with the district’s average.

Three reported G3 orchards were not treated with copper, streptomycin or Acibenzolar S-Methyl between bud burst and harvest yet they outperformed orchards that follow the industry standard of multiple applications of copper to protect against Psa (Table 9).

Table 9. Fruit quality comparison of 3 Agrizest® treated Actinidia chinensis cv. Gold3 orchards with Industry average for the district (as Katikati Nth).

The three orchards are managed using copper judiciously at the conventional rate, timed to protect leaf scar and pruning damaged tissues from infection by Psa and by focusing on orchard hygiene and plant health. All three orchards have produced high quality fruit and have production figures that place them in the upper quartile of performance in this district.

For more information call one of our Orchard specialists today on 09 238 3893.

You can also browse the rest of our website to view some of our trial summaries and data or email us for more information.