Lettuce greenhouse production a constant balancing act, audience hears
By Luke Edwards
Leafy greens grown indoors offer an opportunity for greenhouse operators and a chance to increase Canada’s food sovereignty, but it also has challenges that need to be overcome.
Those challenges can come in the form pests that devour or destroy the leaves before they can be shipped off for human consumption, or with disease affecting the root system meant to feed the plant, or also with a workforce not properly attuned to the needs of the plants.
Fortunately, presenters at the lettuce session of last month’s Canadian Greenhouse Conference had solutions for all those potential issues.
For New Leaf Consulting’s Lucas Chapdelaine, there’s a thing that comes before the thing that comes first, as he was reminded of something he was told in his early days in the greenhouse industry. While the plants come first for any grower, it’s people who grow the plants, so if you don’t take care of your people, they won’t take care of the plants.
“That stuck with me,” he said.
Chapdelaine said the growing team of a greenhouse lettuce operation must have a solid understanding of water and nutrient needs, climate and pest control.
Beyond that, proper tools and systems help the growing team succeed.
“Water treatment is the best money you will spend, if you spend it at build out,” he said.
Chapdelaine offered some other tips, such as the use of polyphosphate iron, which helps ensure the iron survives ozone in the air “so the iron actually reaches your plant.”
And while AI can be a helpful tool, he returned to his theme of people, suggesting it’ll be a human who gets up at 1 a.m. to respond to an issue.
“On the hardest days it’s still people saving the crop,” he said.
Like in any sector, Chapdelaine said there are so-called “miracle” cures out there that promise to fix every issue that may arise. While growers should be open to new products or technologies he encouraged growers to dip their toes in the water before diving in.
“Verify the claims in your own crop,” he said.
Other presenters reminded growers to be vigilant on what’s happening both in plain sight and in whatever growing medium the operation uses.
“What you see above in volume, you should see below,” said Tim van Hissenhoven, who owns a greenhousing consulting company.
Beneficial Insectary’s Greg Bryant, meanwhile, went over some of the challenges of disease, and options to overcome them.
He said dense canopies can make scouting difficult, and encouraged growers to sample known hotspots first. Utilizing flying bugs such as green lacewings in an integrated pest management program can help growers tackle those hard-to-reach spots.
“Let the flying bug do it for you,” he said.
Bryant offered up several options for IPM, with different biologicals providing different benefits. But in the end, he said it comes down to being prepared, having populations on hand before an outbreak gets out of hand, and constant monitoring.
Comments