Can you Garden at Subzero Temperatures in the Snow?

Unless you have a greenhouse, extreme winter gardening in Ontario involves harvesting slow-growing vegetables.  Nothing new is planted here after September except garlic which will be ready sometime in the heat of the following summer. 

All our winter gardening discoveries have evolved from procrastination, laziness and wanting to feed our chickens fresh free organic greens in the dead of winter.  And planting leeks and Brussels’ sprouts in July will not get you a yield before the first frost. 

It is possible to plant a second crop of potatoes in July that can be harvested around the time of the killing frost, sometime in October.  Last year was a warm autumn and we harvested potatoes in early November.  The potatoes are quite susceptible to frost, and once the ground freezes around them, they are never the same again, so aim to let them grow as long as possible before the hard frost.

Choose the Right Vegetables

Vegetables still edible after being excavated from under 2 feet of snow include; curly kale, Brussels’ sprouts, leeks and celeriac.  Nearly all are vegetables that have interminable “days to harvest” on the packet and are a great size by then.  The vegetables do continue to grow in the fall when temperatures rise above freezing during the day.

Cabbages can be successfully grown into the winter, but much past December, the tight headed cabbages go soft inside under the snow.  It seems the open-leaved brassicas like kale do the best when insulated by snow.  Leeks and celeriac are still good to harvest after the snow is gone, though the brassicas are done by then. There are other perennial vegetable and fruits worth growing that are ready in early spring.

I have read that root vegetables such as carrots, beets, parsnips and turnips can be harvested into the winter after the first frosts.  Maybe in milder climes, but with the soil freezing solid here in Zone 5, harvest is physically impossible in the winter.  By spring, those veggies are soft and bendy and not very appealing.

Most of the vegetables grown over the winter are great for making soups and other dishes where texture is not such an issue, but it’s nice to know they are still in good condition.

Any vegetables that disintegrate when  frosted are obviously not suitable.  Check out the seed companies for the best varieties and more vegetable ideas to try.

Winter Vegetable Gardening - Harvesting Brussel Sprouts on Christmas Day

Winter Vegetable Gardening - Harvesting Brussel Sprouts on Christmas Day
Credit: Skeffling Lavender Farm

Herbs that can be Winter Harvested

Rosemary and basil are gone with the first frost, so bring them in to before then.  Parsley, sage, oregano, and chives are fine as long as they are not too dried out in the wind.  We prefer to dry those herbs in the summer, but the odd winter culinary emergency has called for them in the past and they were great. 

Tips for Winter Vegetable Gardening

  • Allow the snow to surround your vegetables completely.  The temperature around your vegetables won’t drop much below 0oC or 32oF. 
  • Place markers or posts where you’re vegetables are-ideally one in each corner of the bed.  It may sound basic, but I have been there, looking for cabbages in 3 feet of snow, knowing ‘they must be round here somewhere’
  • Go dressed for harvesting. Insulated gloves and insulated coveralls and boots will stop you getting chilled. Digging for vegetables in the snow really involves digging by hand.  Using a shovel may damage more vegetables that you want to harvest. 
  • Making a hot, tasty, home-made soup with your buried treasure makes it all worthwhile.  Even if the neighbours think you are crazy!

Growing slow-growing vegetables can take up valuable space in the height of summer. Often they can be planted after early cropping lettuces, spinach, radishes, and peas are done. 

It is worth giving winter gardening a try if you love harvesting your veggie garden and need a hunting and gathering fix in the short days of winter.

Leeks Overwintered, Harvested all Winter and Some Left in the Spring.

Leeks Overwintered and not yet harvested in the Spring.
Credit: Skeffling Lavender Farm