Sweet potatoes

After a recent visit to farm country in the Simcoe area, I have a new found appreciation for the sweet potato.

I knew that the tuber was one of the most nutritious vegetables we could eat; it's chock-full of anti-oxidants, fibre, vitamins and minerals, carotenoids, and it's fat- and cholesterol-free and great for diabetics. What I hadn't considered was that the sweet potato is essentially a tropical vegetable – and yet it grows abundantly south of Waterloo Region in Norfolk County. Add the fact that sweet potato farmers have had to show considerable agrarian acumen and entrepreneurial spirit to grow the vegetable, and sweet potatoes indeed become a superfood. 

Take the case of the Van Berlo family who have a farm near Simcoe.  In the 1970s, farmers had attempted to grow sweet potatoes but failed. The Van Berlos did some some research and took up the cause anew in 1999. Today, the Van Berlos are Canada's largest sweet potato producer, farming about 200 hectares with thousands of kilograms of sweet potatoes harvested each year.

Challenges of growing sweet potatoes

What particular difficulties do sweet potato farmers face? Well, the plants (usually starter "slips" rather than seeds imported from North Carolina) need 150 days of frost-free warmth, so they can't be planted until early June. They also have to be harvested by late September before it gets too cold.

Sweet potatoes are labour intensive to harvest too. So, Peter Van Berlo and his son Nick build the machinery to do the job more easily and efficiently and without damaging the tender crop that grows about 18-inches beneath the soil. 

After coming in from the fields, sweet potatoes must be sorted and cured for a week at a controlled temperature of 30 C. (Andrew Coppolino/CBC)

A positive factor working for the farmers is that sweet potatoes like sandy soil – precisely the soil that once grew tobacco in Norfolk County. That's the entrepreneurial gumption of the farmers that I find so interesting. When the tobacco crops couldn't profit them any longer, they adapted to sweet potatoes.

The other interesting thing about sweet potatoes is – like tobacco– they must be cured before they can be eaten.

After coming in from the fields in 1360 kilogram bins, the potatoes must be cured within a few hours. They cure for a week or so at a controlled temperature of 30 C with 95 per cent humidity. This process converts starches to sugars, enhances their taste, heals cuts, thickens their skins, deepens their colour and extends their shelf life. Uncured sweet potatoes aren't very tasty and won't last more than a week or so, so it's a pretty important process.

How to cook sweet potatoes

When you are buying sweet potatoes look for smooth, even-coloured skins and firm texture. They should have no cracks or bruises. Store them in a cool, dark and ventilated place. 

They can be cooked in many ways: baked, roasted, sliced and grilled, pureed with maple syrup and toasted pecans, or made into a soup.