Nov 2022

Dutch Phytophthora outbreak quickly tackled by Huwa-San

Dutch Phytophthora outbreak quickly tackled by Huwa-San
Accurate dosing and monitoring key for NZ growers

With summer approaching, water quality and reducing the risk of Phytophthora and Pythium (classified as Oomycetes) is what I think is HIGH RISK and HIGHLY LIKELY to affect growers if they do not take precautions. Mitigating the risk of these two problems is achievable using Huwa-San TR 50. Growers, I consult to, are observing excellent results using this product, but as with any product the delivery is crucial for achieving the optimised outcome.

Dosing and monitoring is highly recommended to achieve the best outcomes. A short-term solution is to manually add the product to your main water supply. However, trying to maintain the correct parts per million (PPM), on a system that is continuously refilling with fresh water and fertiliser, may be problematic. Adding a new automatic dosing system is an investment that will give you the highest chance of long-term successful management.

Of course, a grower would want to trial the product before investing in an additional dosing system. However, measuring the success of any trial without automatic dosing will come down to ensuring manual dosing requirements are maintained, to be fair who has time for that. I highly recommend investing into the correct measuring and delivery to achieve the best outcomes.

Prevention is better than cure, this is what Huwa-San does, prevents the issue occurring in the first place. Even for brand new developments I highly recommend a disinfection system is installed from the beginning.

Planting Cucumbers from now – take precautions:

This season I have already observed a new crop that was quickly and severely affected by pythium. Hygiene plays a significant role in reducing this. The weather on the day of planting is luck of the draw. If it is a nice cloudy day that does not get too warm – perfect but are you willing to rely on luck. A grower may have made the correct decisions like irrigating frequently the day and the following few days after planting (keep the water as cool as possible going onto your plants – do not let it get too hot in the PE lines). Even if you do this if you have not cleaned properly between crops or do not have the disinfection in place then you still will have a CONSIDERABLE risk of losing plants. Avoiding chemical interventions is my goal – I see them as a backstop when all other preventative measures have failed. These are a great tool to have in the kit – so please use if required to prevent large crop losses – and do not hesitate. We know you need to make decisions fast for cucumber crops otherwise, they fall over very quickly.


Dutch Phytophthora outbreak quickly tackled by Huwa-San

Vincent Van Riet, a leading Dutch grower of Scindapsus (Epipremnum ‘Aureum’) ornamental plants, experienced a significant issue at the beginning of the year due to a plant pathogen called Phytophthora which resulted in a 50% crop loss.

Phytophthora root rot is a soil based disease that can kill a wide range of plants and is known to have a devastating effect if not dealt with quickly and efficiently. Van Riet turned to Royal Brinkman for a solution and after their assessment of the issue, Brinkman’s technical specialists decided that Huwa-San was the perfect answer help solve this problem.

Roam Technology’s horticultural technical team and Herman Maassen from Royal Brinkman worked together to find the best possible way to drive this infection rate down as soon as possible. The approach, which included flooding the irrigation system with a higher Huwa-San dosage, combined with the installation of a proportional dosing system, was accepted by Van Riet and the project commenced. Onsite support, technical knowledge, regular checks and measurements were all crucial elements in our plan of action.

We were really pleased with the results of using Huwa-San, and with the technical support of both the Roam Technology and Royal Brinkman support teams.

Vincent Van Riet, owner at Dutch ornamental grower Vincent Van Riet

After only 8 weeks, Van Riet could see phenomenal progress in root development, overall growth and element uptake. The plants that were seriously infected by Phytophthora showed systematic recovery thanks to the use of Huwa-San. To date, crop losses have been reduced to almost zero, and the ornamental crops have showed an overall improvement in general plant health. With a harvest consisting of 100.000 plants, this means that Van Riet was able to avoid a loss of approximately 50.000 plants in a single harvest, thanks to the market leading Huwa-San Silver Stabilised Hydrogen Peroxide.

Dutch Phytophthora outbreak quickly tackled by Huwa-San


To learn more about this product contact your NZ Huwa-San distributor

Paul Marlow|  Compliance Certifier/Aquasan International, National Sales Rep
Mob: +64 20 4151 9342
E: paul@educhem.co.nz
Unit 1/36 Bollard Road
Tuakau, 2121



Article written and compiled by Stefan Vogrincic
Extracts and Images – Roam Technology
All Article’s checked and edited by Marie Vogrincic
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