6 July 1992 Scientists Study Day & Night Likes of Cut Flower Species

Lincoln research into the most appropriate day length for the cultivation of various cut flower species has received a boost with funding for a greenhouse blackout facility for horticulturists at the University.

"It's an area not well defined, especially for new crops," says Dennis Farr, who lectures in floriculture at Lincoln. "If you are growing cut flowers all year round in glasshouse conditions you want to know the most suitable day lengths – or periods of light – for the various types you are growing.

"For flower bud initiation and subsequent development some species are very sensitive to day length. The chrysanthemum, for example, responds to short days. On the other hand, lisianthus does not appear to have a marked photoperiod sensitivity, but we will be looking further into that one.

"Working with the blackout facility in the glasshouses at the Lincoln University nursery we will be able to determine the photoperiod response for a whole range of flowers.

"Shortening the length of day through blacking out greenhouses, or extending the day through the use of artificial lighting, are well established techniques overseas but is not, as yet, widely employed in New Zealand.

"Of course with flowers grown outdoors the natural photoperiods change throughout the year – some species need long periods of light, others need short periods, and in the end across a range of species it all balances out. But it is a different situation growing flowers under artificial conditions."

Dr Michael Thomas, who received the research equipment grant along with Mr Farr, will make use of it in relation to pot plants, one of his specialist areas.

Mr Farr points out that the cut flower industry in New Zealand is not well developed or very cohesive, however all the signals are there for a potentially bright future.

"All predictions from the industry worldwide are for continued dramatic expansion over the next few years. An export growth figure of half a billion dollars has been mentioned in relation to New Zealand, but the infrastructure for such expansion in this country is not yet in place.

"At Lincoln we believe we are providing a lead with our research and teaching. We have been teaching floriculture as an undergraduate diploma subject for a number of years and now we are setting up a special floriculture topic at the level of the Postgraduate Diploma in Horticultural Science.

"As a university we are doing our part to have research information available and trained personnel in place to capitalise on the predicted expansion of the cut flower industry."

Ian Collins, Journalist, Lincoln University, Canterbury, New Zealand