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Branch Newsletter & Local Meetings



July Newsletter


First of all I would like to apologise for the late bi-monthly newsletter, unlike many wiser, more punctual secretaries before me, I have yet to master the art of juggling many activities simultaneously, I may have to take some pointers from my better half&..

I can report that our first site visit of the year went off seamlessly, and even though we could not visit all the areas of the farm our hosts sure made the experience valuable and engaging. Arriving to a farm on a Thursday night during winter at 7pm in pitch darkness, off Tram road, about 10 minutes from the highway turn off, seemed to be a very strange place for a group of predominantly retired electrical tradesman and electronic technicians to meet. Puzzled nor confused were looks not found on members faces who eagerly waited for our host to kick off our tour, instead a quiet hum of excitement and curiosity hung in the air, just like the crisp winters night that greeted us before the frost set in.

Dave Barton our host lead us through to the main office, which to everyones humble relief was heated. The office was a simple yet effective set up, in one corner sat a typical receptionist desk, while immediately in front was a smaller computer set up for someone who appeared to spend more time running around getting stuck in rather than sitting down for 8 hours a day typing furiously away on a new novel. Dave took us though a very enjoyable history of how he started off in the horticulture industry, filling in all the details of his journey right through to his current situation, reviewing his retirement and potentially handing the reins over to new pioneers. As Dave explains in detail how the operation of growing cucumbers is undertaken, you could have easily mistaken yourself as being on a live set of country calendar, you find yourself being more intrigued every time he explains the process of growing cucumbers. It was about 10 minutes into our tour when Deirdre, Daves wife and Business partner accompanies us, chipping in with snippets of information, providing a different view point of Daves recollections.

As Dave takes us through the intricacies of his greenhouse control system I cant help but wondering how this simple outdated computer which appears to be running a windows XP operating system is the backbone of this whole operation, I guess the old saying is true, if ant broke dont fix it. The control system utilises information from multiple temperature and humidity sensors located inside the glasshouses and enthalpy and lighting sensors outside the glasshouses. The sensors reading are feed through a custom software program which utilises algorithms and logic which in turn control the actuated windows, water boilers, generators, water valves and many other facets of the growing operation.

After reviewing the control system, we take a tour through the first plant room; due to the farm being separated by Madeleys Road, two separate plant rooms are required to power the whole operation. As part of good contingency planning, there are spare generators and parts ready to put into service for any breakdowns. The first plant room is powered by a diesel boiler and sizable generator.

The second plant room is much newer, in one shed is the boiler and generator and in the other is the fertiliser, spray and pump room. The boiler roars into life while we are there, bringing the water up to temperature in about 10 minutes, it appears humble in size but when dealing with raising over 10,000L of water over 10°C the MW rating of the boiler is surely required.


Second Plant Room Genset 15kVA (approx.)



Second Plant Room Diesel Boiler

To finish off the night, Deirdre and Dave invited us for tea and coffee at their house and shared more of the greenhouse adventures.


Below is Stars recount of our visit:

8 people attended the meeting on Thursday 10th May 2018 held at Island Horticulture, 38 Madeleys Road, Kaiapoi.

David and Deirdre Barton our hosts, gave us a talk about the challenges of growing cucumbers, which they have been doing for the last 35 + years. Prices paid to growers are the same now as they were 20 years ago. Consequently this has squeezed out the small sized growers and Island Horticulture is now the only commercial cucumber grower in the South Island. Not only does Island Horticulture have a large area under "glass" (2 hectares), they are also using technology (computer controlled systems) to help remain in business. Island Horticulture provide cucumbers all the year around to Foodstuff South Island. Although producing cucumbers during the Winter is likely to furnish a financial loss for that period, it is required by the contract with Foodstuffs. However, of course this contract does enable a profit to occur when the whole year is considered.

Of interest, Island Horticulture must be considered to be a low carbon emission establishment as it qualifies for carbon credits.

Cucumbers, like all plants/vegetables will produce poisons if they feel threatened by any competition. These poisons can have an effect on taste etc. To prevent this, it is important to provide a stress-free environment. David told us that no matter what method is used to grow a vegetable (eg. organic etc.) it will have no effect on the taste providing the plant has not been stressed.

Island Horticulture receive cucumber seeds from the Netherlands. Each one of these are put in a bed of coca peat which is in its own small box with an open top. They are then placed in the propagating room which is sprayed for white fly. Each plant grown from seed is a female and can have offspring which are also female. These offspring can also have offspring (also female), however, after this, no more generations of offspring are produced.

One of the parameters that the computer software controls, is temperature in the glass houses by operating shades and controlling hot water when heating is required. Not only does this ensure that the plants do not get too hot or cold, it is also cycled between two values during a 24 hour period. By altering the temperature difference, plants will perform differently. In order to get them to produce offspring the temperature difference is increased. This will encourage the plant to have offspring as it thinks that it will soon die. If the temperature difference is small it will continue to put its effort into growing.

To provide a 30% increase in plants per area, cucumbers are grown hydroponically, so water quality is important. During summer each one of the 40,000 cucumber requires 3.2 litres per day. The way some other business are treating their environment has had an effect on their water quality. For example, leaf mould from the spread of effluent of a dairy farm, and an increase in PH level due to too much fertilizer being spread on another farm. This has meant that a water sterilizer is installed which also does their drinking water.

Island Horticulture employ 20 people and have two large "glass houses" (one for prorogation and the other for growing). Both houses have oil fired boilers and back up alternators. Their peak demand is 24MW. The growing house has 12,000 litres of water in its heating system, of which the boiler takes 5,000 litres. The heat from the boiler is transferred to the plants by using pipes that are installed throughout the house.

Island Horticulture have both plastic (double layered with a gap between) and glass cladded houses. Plastic cladding lasts 6 years and performance wise glass seem to be better.

At the conclusion of the meeting our host kindly gave us a cuppa and bickies and Levi then thanked our hosts


I hope to have another meeting organised for October, keep your eyes out for Septembers newsletter

Many Thanks

Levi Martin

Secretary/Treasurer Christchurch Branch, Phone: 027 562 7846 E-mail: levi@ecandc.co.nz


Canterbury Electrical Society has invited us to their next site visit at Canterbury University;


Solar Water Heating

Date & Time:

Tuesday 14th August 2018 starting at 2pm


21 Gatherer Street




Nick Williamson




2 full days to SHOWCASE, EDUCATE and SELL 

directly to hundreds of industry professionals and decision makers.

  Celebrate Kiwi innovation in the heartland of manufacturing at SouthMACH.

South Island's leading trade show for the engineering, manufacturing and technology industries.  

Don't miss out! 2019 is gearing up to be the best show on record.

Showcase your innovative products and service solutions.
Educate your customers on the latest technologies and industry best practice.
Sell to a qualified and targeted audience. 






*SouthMACH 2017 Visitor Research



Check out SouthMACH 2017 to see what it's all about:


With over 25 seminars & workshops planned for 2019, this is a great way to upskill the industry

The latest in manufacturing and technology on display plus marvel at what new start-ups are thinking up at "The Lab"

Help combat the skill shortage in the industry and meet potential employees through "SpeedMeets"




New Zealand Electronics Institute Christchurch Branch


2017 Annual General Meeting

The annual general meeting of the the Christchurch branch of the New Zealand Electronics Institute (Inc) was held on 16th November 2017.


Chairman's Report

2016 Minutes

  Bookmark this page in your web browserwww.nzelectronics.org.nz - Christchurch News