Orchardists Look For Frost Protection
June 12, 2006
Cold Start To June Sees Orchardists Look For Frost Protection
A frosty start to June has seen many orchardists looking for new ways to protect their valuable orchards from freezing temperatures.
NIWA climatologist Stuart Burgess says although there have been a number of frosts in the past week, the outlook is for June to balance out to be an 'average' month. Burgess says in an average June, 12-13 frosts can be expected.
However, kiwifruit growers are still watching the weather forecast closely and employing various methods to keep their orchards safe from frost.
Whakatane orchardist Marco Crivelli says he worries less about frost these days after discovering the organic product 'ThermoMax'.
"My best defense against frost used to be to bite my fingernails. Not surprisingly it didn't work, and it hurt," Crivelli says.
"After losing half my crop one year I decided I had to find a solution. I discovered ThermoMax and these days I don't have to worry so much."
Made from garden herbs valerian, dandelion and chamomile, ThermoMax is sprayed directly onto the kiwifruit vines. It works by stimulating the plant's metabolism, effectively warming it up from the inside.
Manufactured by Te Puke company BD Max, ThermoMax is a completely organic and homeopathic treatment.
BD Max director Glen Atkinson says more orchardists are using ThermoMax, both as a stand-alone treatment and as part of a combined frost protection defence.
"Over the years numerous new ways have been developed to reduce the risk of frost injury. Wind machines and helicopters can be used to raise air temperatures by mixing freezing air with warmer air where a temperature inversion exists. Overhead sprinklers are also used. However these technologies are expensive and not always successful.
"ThermoMax activates the phosphorus metabolism within the plant, which allows it more internal warmth. This provides an internal two degree warmth cushion, which can be used by itself, or provide a great starting place for all other frost protection methods," Atkinson says.
"An increase of two degrees in the spring also gives the plants a growth head start as well."
HortResearch climate room trials showed ThermoMax could provide a 50% increase in crop yield at a –2C frost*. Similar results have been achieved on avocados, grapes and tamarillos.
Crivelli says he has been recommending the product to his orchardist neighbours and friends.
"It's very clear how well the ThermoMax works. When you go out in the morning after a frost you can clearly see where you've sprayed the product – all around the sprayed area is white with the frost, but the plant you have sprayed is not icy."
*For full HortResearch trial results visit www.bdmax.co.nz