Greenhouse crops have been a focus at the Centre since the 1940s, with the first research greenhouses constructed in 1948, according to retired researcher Dr. Gordon Ward. He wrote the Greenhouse Vegetables report published during the Centre’s 75th anniversary. Prior to 1947, the Centre – then called the Dominion Experimental Station – had several greenhouses, but they were used to grow tobacco transplants. “The greenhouse vegetable industry has changed a lot over the past 20 years, much higher yields are realized, production is on a more scientific basis, and many major problems have been faced and resolved,” said Dr. Ward. “Greenhouse vegetable research at the Harrow Research Centre has played a major role in this change.”

Several features in our August 2009 edition took a closer look at the history of research at Harrow. It’s a fascinating recap, offering a brief sampling of some of the work.

Mass production of Encarsia formosa was started by Dr. Bob McClanahan at the Centre in 1970-72, with considerable support and encouragement by local growers. “In 1974, Better Yield Insects Co. was formed in Ontario and started the first commercial production of E. formosa and Phytoseiulus persimilis, a predatory mite for two-spotted spider mites,” noted Dr. Les Shipp (AAFC) and Gillian Ferguson (OMAFRA) in the August issue. “These major accomplishments were the start of the commercial greenhouse biological control industry in Canada.”

The Centre has had decades of experience in assisting with powdery mildew controls, most recently focusing on new reduced-risk materials.

In 1987, Centre researchers began studying cover materials and demonstrated that tomato and cucumber yields are about the same under double poly as under glass, with the added benefit of a 30 per cent energy savings with the former. As a result of these findings, many of the greenhouses constructed in Leamington are double poly. It’s estimated the move has meant construction savings of close to a billion dollars and energy savings of 30 per cent, as compared to glass.

Grow-pipe research at Harrow, among other projects, has significantly improved microclimate management, leading to improved fruit quality and less disease.

Harrow has long been a major contributor to the success of the Canadian greenhouse vegetable sector. And it’s had great partners, with companies and growers helping sponsor research and supply project ideas. Growers in every region of Canada have benefited from work done there.

It's time to celebrate!