MEAFORD -- Fruit growers around Southern Georgian Bay fear the worst is yet to come as Mother Nature tosses a curveball this spring.

So far, Tom Ferri says he doesn't see any obvious signs of damage from the cold weather when he peels open a bud from one of his apple trees at TK Orchards.

But he knows the wintry weather isn't over just yet.

"It's when you get the clear, calm nights the temperature will really go down, especially when you are in a polar vortex like this when your daytime highs are only three or four degrees if you are lucky," says Ferri.

The apple farmer plans to watch the thermometers closely and operate large fans to prevent cold air from settling.

Farmers typically use low-flying helicopters to mix up the air, but this season the pandemic has grounded them.

"We are at a stage that isn't real critical, but if we were in bloom across Georgian Bay, this would be a really nasty night," Ferri says.

Some early varieties of apples are more advanced in development and will become more vulnerable to freezing temperatures, along with tender fruits like cherries and peaches.

It will be a few days yet before fruit growers across the region know the full extent of damage from the cold weather.