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The Best Tips for Growing Onions

Updated: Jan 6

Onions are a vegetable used nearly daily in many of our kitchens. Onions are a cold hardy crop that grow well in the zone 3 gardening climate of Canada and other parts of the northern hemisphere. Onions belong to the allium family and can be beneficial in your garden as a companion to many plants as a pest deterrent. (See below.)

When planting long day onions in your garden in zone 3 Calgary, Alberta Canada plant onions in late April or early May.

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For many years I struggled to grow onions. Each spring I would plant onion sets around the end of May and by September most would be only slightly larger than my garlic. Thankfully some research, along with learning from mistakes I had made, pointed me to where I was going wrong and last year was my first ever, very successful onion harvest! Let me share with you a few tips for growing onions that I have found out over the past year.

3 Mistakes I Made When Planting Onions

  1. Not making sure I was growing intermediate day, or preferably, long day onions.

  2. Planting too late in the spring. (End of May vs. end of April).

  3. Planting the bulb too deep.

Let's take a look at the varieties of onions we should be growing in Canada.

Long Day vs. Short Day Onions

Onions are photothermic. That means they need enough hours of daylight to grow to their full potential.

One of the most exciting tips I have learned for growing onions is that there are long day, intermediate day and short day onions. Up here in Canada in the northern hemisphere (or in latitudes 37–