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February 23, 2009  By Gary Jones

My local community newspaper does a weekly “Readers’ Poll.” A recent question was “What’s the biggest topic of conversation at your dinner table these days?1.Results were (with my rounding errors):

My local community newspaper does a weekly “Readers’ Poll.” A recent question was “What’s the biggest topic of conversation at your dinner table these days?1.Results were (with my rounding errors):

1.  The weather                 28 per cent.
2.  Politics                         18 per cent.
3.  Religion                        4 per cent.
4.  Financial crisis              24 per cent.
5.  War                             4 per cent.
6.  What’s for dessert?       22 per cent.


At first, I was struck by the notion that the paper thinks families still manage to sit around the dinner table and share a meal together. Oh, if that were true, indeed it would be great for society generally, but that’s a topic for another day. No, what caught my interest were the options.

It’s great that four per cent of respondents (no sample size given) still find time to talk about religion. Great idea. Shame that 28 per cent found the weather more important. (More immediate, I guess.) I realize the poll is only a harmless bit of fun, and maybe I’m a little more interested in food production than many others, but the only mention of food was “what’s for dessert?” There is an unwritten expectation that there is a dessert. How blessed we are.

Two days later, at the AGM of the B.C. Institute of Agrologists, the regional director spoke about the role of the Canadian Food Inspection Agency (CFIA). Hosts of new pests and diseases seem to be eating away at the food we grow, meat we raise, or timber we produce. But apart from a few high-profile cases, the public hear little or nothing of what goes on to help ensure we enjoy regular supplies of safe food – our “just desserts.”

A fire and closure of a major arterial road bridge causes traffic chaos in the Greater Vancouver area for several weeks. What if that closure goes longer – for perhaps a few months? What if that bridge were a major transportation corridor for food products grown some distance away (California, for example)? Having access to very local food is suddenly looking to be a real area of vulnerability in the long term. To many, a local greenhouse industry may suddenly seem attractive; if they think about it, that is.

But there are challenges. Heavy snowfall on greenhouses resulted in a number of facility losses in B.C. this winter. While few were producing food crops, and most were running with little heat, nonetheless, roofs and structures buckled and collapsed under the weight of deep snow. (Incidentally, it’s a great idea to remove, or at least cut, poly covers if you know its going to snow heavily and you have no crop in or heat available – better to re-skin the house than have to start with a new structure.) Even “high-tech” and relatively new greenhouses were not immune to Mother Nature’s pressures, and builders will be tackling some unexpected renovations and repair work this spring.

The greenhouse structures that many of us spend much of our time in are designed to rigorous specifications. But, of course, they’re not designed to withstand every weather condition; just most of them, and with a necessary element of compromise to avoid building such “bomb-proof” structures that costs would be unrealistic or light transmission so low that crop yields would be compromised. Even if over-designed, the durability and performance of the structure still depends on many factors such as how well it is actually put together, quality of materials, age and maintenance.

Once built, the structure has to perform to its design standards. That means having suitable control systems and someone with the knowledge and experience to manage that system to its optimum. Computer environmental control systems may now seem essential, they are really just tools for the grower to increase knowledge, develop skills and maximize crop productivity. Like Vancouver’s bridges and the CFIA system, good greenhouse structures and control systems ultimately help provide the consumer with some food security. Even if to many, like a familiar bridge, it’s simply taken for granted … until it’s not there.

1Thanks to the Langley Advance for this!

Gary Jones is Chair of Production Horticulture at Kwantlen University, Langley, B.C. He serves on several industry committees and would welcome comments at

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