Features Structures & Equipment Water and irrigation
Inside View: Augut 2007

Water, water everywhere…but for how long?  "If you’re planning expansions or renovations, consider re-circulation systems."

ccording to the U.K. Meteorological Office, April was the warmest since records began there in 1659 (yes, that date is right! U.K. Met Office data). The mean temperature was 11.1ºC, 3.2ºC above the average for April. I’m pretty sure it’s not the same person doing the measuring now as then, but it’s very reliable data.

And while many growers still enjoy the luxury of abstracting water locally from rivers or aquifers, if the warmer weather continues then no doubt at some point the regulatory agencies will limit this privilege.

What’s going on? Without going all ‘Al Gor-ian’ so to speak, clearly something is a little different and things will likely continue to change. Whether facing times of severe drought or times of unbelievable water excess, securing and managing a reliable supply of high quality water is becoming an increasingly important challenge for most growers.

WHAT CAN YOU DO?
• Investigate all your sources of water – aquifer (well), river/stream, mains/city, on-site collection from covered ground or greenhouse roof.
• Check its suitability for growing your crops, i.e., quality (get it tested at your local lab).
• Check quantity available throughout the year – peak availability, average flow rate.
• Consider ‘blending’ different supplies to:
• reduce reliance on any one specific source
• improve quality of the major supply
• reduce costs of using city water
• Do what you can to reduce water use.

REDUCING WATER USAGE
• During summer months, consider some of your options for reducing water use. These might include:
Use efficient application methods:
• Trickle irrigation
• Drip tape/hose, rather than overhead sprinklers
• Sub-irrigation – troughs, gutters, flooded floors.

If you have the capacity, schedule your irrigation applications to reduce water losses from evaporation, or to match those times when your crop species makes best use of the water it receives. This information is available for many horticultural crops from irrigation specialists.

Use pot covers or mulches to reduce evaporation from soil.

For field grown crops, build up a healthy soil – incorporate plenty of organic matter, avoid compaction and reduce tillage.

If you’re planning future expansion or renovation of your facilities, consider incorporating re-circulation systems. These can obviously be included in new greenhouses, but container nursery producers in the U.K. have proven that they can equally benefit from this in terms of reduced water and fertilizer wastage.

If you have the option, plan on growing species that are more drought-tolerant. Include a specific area of the garden centre with clear signage for drought-tolerant species. Or perhaps you can develop a niche for drought-tolerant plants to be used in your wholesale landscape contracts.

INFORMATION, MONEY AVAILABLE
• Do your best to follow Best Management Practices for water management and irrigation. If you need to know more, grab yourself copies of the Best Management booklets from Agriculture Canada or the Ontario Ministry of Agriculture, Food and Rural Affairs. These might be 10 years old now, but they’re great working manuals, and even better – they are free!

Also, when investigating some of these items, check with your local Environmental Farm Planner (EFP), since some items might attract funding to help you implement them.

If some of this seems to be a little too drastic, consider that models developed at the University of British Columbia predict that by the year 2050, the Okanagan region will likely be too warm and dry to support the wonderful top fruit industry that it currently enjoys, and yet the Prince George area will by then be able to support the production of pretty much all crops but bananas!

Still don’t think water is an issue?