Is this the end of lettuce? Why Canada’s food supply is headed for uncharted territory

Picture the Titanic, except filled with lettuce instead of passengers. Now picture five Titanics filled with lettuce, plus another half-filled ship. Picture this armada of ships, laden with romaine, spring mix, red leaf, green leaf and iceberg, all setting sail for Canada.

This is how much lettuce our country imports every year: 265,000 metric tons in 2022 alone.

Almost all of it comes from the U.S., and the majority from one state: California.

For years, this fleet of imported lettuce arrived without incident, supplying a steady stream of leafy greens to our frostbitten country. But in the past six months, leaks appeared.

Last fall, heat, drought and disease coalesced to blight lettuce crops in California so severely that for a few weeks, lettuce abruptly vanished from Canadian grocery store shelves. What little was available cost, in some cases, 500 per cent more than usual.

Supply stabilized somewhat as production shifted to Arizona over the winter. But this spring, when lettuce imports would normally switch back to California, flooding from a relentless torrent of atmospheric rivers and unusually cold temperatures delayed the crop, pinching supply again.

California is being hammered by climate change, compounding long-standing water woes and natural weather extremes. The impact on Canada may be most obvious in our lettuce supply, but evidence of their climate and water stress can be found all across the produce aisle, if you know where to look.

Approximately three quarters of all fresh fruits and vegetables consumed in Canada is imported, and California supplies a major chunk of that. Our dependence on the state means that California's environmental woes are ours, too - and the impacts can be felt in our fridges, grocery bills and even on our health.

I don't want to be, you know, doomsaying, but I mean, we are currently depending for almost all of our fruits and vegetables on one small geographic region, which is currently in a drought. And that drought is expected by all estimations to probably be worse over the next 10 years," says Evan Fraser, director of the Arrell Food Institute and professor of geography at the University of Guelph.

If California can't produce and export with the same level of stability and predictability and costs that it's had over the last 20 years, the implication of that is going to be higher prices and periods of disruption."

Our food system is already shifting in response, with Canadian farmers moving some crops indoors to create a stable, homegrown supply of vegetables at least partially protected from the vagaries of mother nature. Experts say these solutions hold promise, but barriers remain to rapidly scaling up.

In the meantime, Canadians are feeling the heat. More than three-quarters of us don't eat enough fruits and vegetables already, with cost being a major barrier. While it's hard to disentangle the various causes of food inflation, environmental crises are definitely playing a role in the stubbornly high price of groceries.

All these things add continual upward pressure on our food prices at a moment of very, very high food price inflation, where an eye-watering number of Canadians cannot afford to eat a healthy diet," Fraser says.

You don't need an advanced degree in agricultural economics to understand why Canada has looked south for a stable, year-round supply of fresh vegetables. If you've ever moped around in February wondering how anyone could survive on such little sunlight, imagine being a carrot.

This country's trade deficit in field vegetables - how much more we import than export - reached $1.5 billion last year, according to Agriculture and Agri-Food Canada. The U.S. is our biggest supplier, and the largest proportion of most U.S. field vegetables are from California. Arizona, which has its own water problems, is also an important provider, especially of lettuce.

This imbalance is a long-term structural problem," says Rod MacRae, professor emeritus at York University's Faculty of Environmental and Urban Change.

We used to be way more self-reliant in fresh fruits and vegetables - we produced a lot more of what we consumed domestically. And since World War Two, all that has seriously deteriorated, largely because there's very limited policy supports for it compared to, say, the grain or the animal sectors."

For some veggie staples - the kinds your doctor probably wants you to eat more of - the imbalance is hefty. Canada produced 65,500 metric tons of broccoli and cauliflower last year, and imported more than double that amount, according to data supplied by Agriculture and Agri-Food Canada. We grew 103,000 metric tons of lettuce, and imported more than two and a half times as much. We grew 6,700 metric tons of spinach, and imported five times as much.

Canada also doesn't eat everything it grows - we export a lot of fresh vegetables, too. Last year, Canada participated in a massive cross-border carrot swap, exporting 98,579 metric tons and importing 98,626 metric tons, nearly the exact same amount.

That happens for a few reasons, a spokesperson for Agriculture Canada says. North-south trade between the U.S. and Canada can mean shorter distances, and therefore lower costs and carbon emissions, than east-west within this enormous country. It's also because vegetables are perishable: when we produce a glut that can't be eaten before it spoils, we export the excess. On the flip side, even with domestic greenhouse production, Canada must import fresh tomatoes in February and March from outside Canada to satisfy consumers who wish to consume tomatoes fresh at that time of the year," the spokesperson says.

For the four field vegetables mentioned above - broccoli and cauliflower, lettuce and spinach - approximately two-thirds of imports came from California. The state supplied half of our cabbage and kale imports, and 80 per cent of our celery imports. In the middle of winter, California, Arizona and other hot U.S. states would provide an even higher total for many fruits and vegetables.

For years, this arrangement worked pretty well. But now, California is running out of water.

The state's primary agriculture powerhouse is living on borrowed time," says Christopher Schwalm, director of the climate risk program at the U.S.-based Woodwell Climate Research Center.

California's Central Valley extends like a pointed index finger through the middle of the state. Aside from producing billions of dollars worth of agriculture exports - Canada is the biggest buyer, ahead of the European Union and China - the region also supplies a quarter of all the food eaten in America, according to U.S. government figures. Jutting off the Central Valley like a thumb is the Salinas Valley, dubbed the Salad Bowl of the World" because of its vast production of leafy greens.

Crops love this region for the same reason people do: it's always sunny.

Every summer here, from basically the middle of April until October or November, there is essentially zero precipitation," says Jay Lund, a professor of civil and environmental engineering at the University of California Davis.

The lack of rain is, ironically, ideal for producing high yields, Lund says: farmers tightly control the water for crops through irrigation, using what they need rather than relying on boom and bust cycles from the sky.

We don't have those thunderstorms that are coming in and flooding your field in the middle of high growth," Lund says.

But to supplement water collected in reservoirs, farmers have been pumping groundwater from underground aquifers. Starting in the 1990s, Schwalm says, the region began pumping more water from below ground than could be recharged by rain every year.

So much groundwater has been pumped out that parts of the Central Valley are suffering from a phenomenon known as subsidence": the ground is sinking as aquifers below it are depleted, in some places by as much as nine metres. Aquifers closer to the coast have seen seawater intrude as groundwater levels drop, risking the water becoming unusably salty. Some Californians have discovered their drinking water wells draw nothing but sand.

This winter's back-to-back atmospheric rivers, heavy storms that have also been supercharged by climate change, have replenished some aquifers, but not all.

We're still fundamentally short on water," Schwalm says.

Climate change is exacerbating the situation in multiple ways. It increases the risk of drought, which means less rain to recharge the aquifers. It also increases evaporative demand": hotter, drier air means more moisture is absorbed before ever making it underground. And crops, especially ones such as lettuce that require moderate temperatures, need more water to stay cool and healthy.

In-house analyses by the Woodwell Center show that a big chunk of the Central Valley ranks among the worst regions in the world for water scarcity, Schwalm says.

They really have the worst end of the stick that is possible," says Schwalm, who is based in Arizona. (Arizona has its own water issues, relying on the heavily overdrawn Colorado River; agriculture will likely also take a hit there to keep the river from dropping dangerously low.)

In 2014, California's governor signed a law called the Sustainable Groundwater Management Act, which requires local agencies to come up with plans and set limits on how much water is pumped from underground. Last year marked the deadline for when regions had to submit plans to use groundwater sustainably and start implementing them.

Lund says it is unavoidable" that cropland will be fallowed to compensate for the reduction in water supply, since agriculture uses about 80 per cent of the water in the state.

He estimates anywhere from 15 to 20 per cent of irrigated land in the state will be retired from agriculture; other estimates vary, but are at least half a million acres.

Lund predicts that farmers, who have had to fallow their fields during bad droughts in the past, will cut back on less profitable crops like alfalfa and corn first; the high-value vegetable commodities are likely to be preserved.

That doesn't reassure the University of Guelph's Evan Fraser.

It's not only will they continue to produce, but will they continue to export to Canada? And will they continue to export to Canada at prices people can afford?" he asks.

Climate change isn't going to destroy agriculture, but it is going to make food harder and more expensive to produce."

Experts the Star spoke to differed in their predictions of how these changes will ultimately alter Canada's food supply. Some say our diets will have to change, others disagreed. Some say technology will save the day, others were skeptical. Supply is one part of the equation, demand another: will anyone buy cauliflower if it costs $12 a head?

It's incredibly hard to predict," Schwalm says.

Maybe the most mind-blowing thing about the many, many Titanics-worth of produce that arrives at Canada's borders yearly is that it's still not enough to nourish everyone. The percentage of Canadians who report eating at least five servings of fresh fruits and vegetables daily - the amount the World Health Organization recommends for optimal health - has been dropping steadily year over year.

Just 22 per cent of Canadian youth and adults consumed at least five servings daily in 2021, a decline of almost 10 per cent in less than a decade, according to Statistics Canada. The biggest reason for not eating more fruits and vegetables is cost, a survey by the Agri-Food Analytics Lab at Dalhousie University found.

We have seen just eye-watering rates of food insecurity in this country in the last year in response to food price inflation," says Fraser, pointing to recently-released results from the Canadian Income Survey. More than one in five Canadians lived in households experiencing food insecurity in 2021, a jump of 1.1 million people in a single year.

Simply boosting vegetable supply is not enough to combat this problem, Fraser says - It's hard to imagine a scenario where anybody can afford salads if you're spending $4,000 bucks a month on a studio apartment," to pick one socioeconomic stressor.

But without action, the problem is only going to get worse.

I'm worried that if what we see is rapid food price inflation, specifically on fresh fruits and vegetables, we will exacerbate an already terrible food insecurity problem in our country," he says.

In Canada, some crops are already moving inside. Significantly more peppers and cucumbers are grown in Canadian greenhouses than in the field, according to Agriculture Canada data - for cucumbers, it's more than five times as much. A modest amount of lettuce was grown indoors last year, around 20,000 metric tons, less than one-tenth of what we import. But while peppers, cucumbers and tomatoes saw incremental gains in greenhouse production over the past five years, indoor lettuce production almost tripled.

When asked about the country's reliance on fresh vegetable imports, a spokesperson for Agriculture Canada wrote that the indoor agriculture sector is the largest and fastest growing segment of Canadian horticulture" - a sector that includes both traditional greenhouses and futuristic-seeming vertical farms.

Going forward, the department anticipates that (greenhouse) vegetable production and acreage will continue their multi-decade trend of growth," the spokesperson says..

Vertical farming is a nascent but increasingly high-profile form of indoor agriculture where even more of the environment is controlled. A big advantage of vertical farms is efficiency: lots of lettuce can be stacked on not a lot of land, and they are designed to use very little water. Salad mixes grown in vertical farms are already available in Ontario grocery stores, and researchers are experimenting with other crops.

Both greenhouse and vertical farming can produce greater densities than field. Every day is a good weather day," says Thomas Graham, a professor and research chair in controlled environment systems at the University of Guelph.

But the biggest elephant in the room," he says, is energy use: providing enough light and heat to sustain these crops can drive up prices and complicate the sustainable" label, depending on the power grid that supplies these ventures.

Fraser says vertical farms are a helpful tool, but not a panacea - and points out that to replace the 265,000 metric tons of lettuce imported annually, Canada would have to build something like 265 vertical farms.

It's good to have a local source of salad," he says, but it's not a food system."

Kate Allen is a Toronto-based reporter covering climate change for the Star. Follow her on Twitter: @katecallen