2
Jul 2018

Using Screens in New Zealand Conditions

Using Screens in New Zealand Conditions

Using Screens in New Zealand Conditions

Its time to start thinking of new options.

 

Last week at the Australian HFF conference in Melbourne a presentation was given by Ton Habraken, Greenhouse Climate Consultant for Ludvig Svensson, about his company’s greenhouse screens and their climate control possibilities.   It was an excellent presentation which has relevance for New Zealand greenhouse growers moving forward.

The use of screens in New Zealand, especially Auckland and North of Auckland, has not always been considered as a ‘must have’, due to our moderate climate.  However, with the introduction of new types of screens, and not just energy screens, the viability of faster returns on investment is now possible.

Some grower’s current structures mean retrofitting is probably not on the cards, but for some existing greenhouses, especially new builds, it is advised to at least do the numbers. 

Years ago, the perception I had was screens would only assist with shade and a small saving in energy.   I was taught many years ago, whilst growing tomatoes, that shading your crop in New Zealand conditions is counterproductive. If you did shade you would create soft plants, less roots etc etc.    In 2018 however, screens have evolved and there are many more options that suit our conditions, which will contribute to energy saving and better light transmission. Newly developed diffused screens act both as an energy screen and light scattering.  Diffused screens are already in many properties in the greater Auckland area, they are especially popular with cucumber, eggplant and capsicums growers.  Imagine, during the hard frosts we had in the mornings last week, if you had a screen which kept the warmth in and allowed light to penetrate into the crop without having to close the screens totally until late in the morning.

The screens available are versatile.  For capsicum growers who need screens in the summer, the Harmony screen, which is used for diffusion, shading and cooling, is an option to be considered.  Tomato growers should consider the Luxous range, which lets more daylight reach the crop while saving energy.  In the warmer months, if you want to protect your crop, you will not be able to use your screens but you can always use diffused coatings on your glasshouse roof to protect your crop.

With what appears to be the imminent arrival of medicinal cannabis growing in New Zealand, Svensson has the Obscura range of black out screens.  These are installed for cannabis growers as they need a set period of darkness each day.  These properties will also be equipped with supplementary lighting. 

For countries in the Middle East, where there is plenty of usable light at the start and end of the day, screening can help reduce greenhouse temperatures by up to 10 degrees in the middle of the day.  Screens are fitted on top of the greenhouse to achieve this!

Harmony = high grade light diffusion

Luxous = energy saving with maximum light transmission.

 

I appreciate your comments.  Please feel free to comment below or on the grower2grower Facebook page:

https://www.facebook.com/StefanGrower2grower/

Article Written by Stefan Vogrincic, Consultant, Grower2Grower

 

CLASSIFIED

Subscribe to our E-Zine

Sign up here to subscribe to the Grower2grower Ezine. Every two weeks you will receive new articles, specific to the protected cropping industry, informing you of industry news and events straight to your inbox.

More

From This Category

Australian horticulture’s $1 billion annual productivity opportunity
July 29, 2025
Australian horticulture’s $1 billion annual productivity opportunity
Over the past 30 years, the annual productivity growth of the horticulture industry has been 0.5% to 1.5%
Powdery Mildew: EPA approves Rhapsody, a fungicide containing 218 g/L ipflufenoquin, a chemical new to New Zealand
July 29, 2025
Powdery Mildew: EPA approves Rhapsody, a fungicide containing 218 g/L ipflufenoquin, a chemical new to New Zealand
The Environmental Protection Authority (EPA) has approved a fungicide with a new active ingredient that controls blackspot and powdery mildew on apples and pears, and Botrytis on grapes.
Calling on suppliers to do the right thing (Hygiene)
July 14, 2025
Calling on suppliers to do the right thing (Hygiene)
"Every part of the sector has a role to play in Biosecurity" (Dinah Cohen, GM TomatoesNZ) 공급업체들에게 올바른 행동을 촉구합니다
Cravo Cricket Houses: New Zealand’s Game-Changing Training Facilities
New tomato varieties from Bayer offer protection against resistance-breaking Tomato Brown Rugose Fruit Virus (ToBRFV)
June 17, 2025
New tomato varieties from Bayer offer protection against resistance-breaking Tomato Brown Rugose Fruit Virus (ToBRFV)
Bayer is using multi-stacked virus-resistant genes to bring more durable protection against ToBRFV mutations / Developed through advanced conventional breeding techniques, new hybrids will be available this year in every major glasshouse tomato segment
Tomato Prices on the rise as winter begins to bite
June 17, 2025
Tomato Prices on the rise as winter begins to bite
Farmgate values solid in New Zealand and Australia. In New Zealand, farmgate values (FGV) for the standard large loose round tomato are pushing into the $7–$8/kg range this week — a significant jump. Meanwhile, retail prices have soared, with some stores charging as much as $14.99/kg for loose rounds as of Monday.
CLASSIFIED