Onions in SW Ontario

Nestled in the heart of southwestern Ontario, Chatham-Kent stands as a testament to the bounty of nature. Particularly noteworthy is its classification as a Zone 6b region by the Canadian Plant Hardiness Scale. This distinction makes it an optimal location for growing a variety of plants, for this article’s focus, we will discuss long day storage onions, which thrive in this specific climate.

Long Day Onions?

In Canadian gardening zones, the choice of onion type to plant—long day, short day, or intermediate (day-neutral)—depends significantly on the specific zone and its associated daylight length. Again, Chatham-Kent is in zone 6b.

Without over thinking it too much, you might remember that the days get longer in the summer, which is directly related to our latitude. The lengths of days tend to average out overall, but as a simple example, the days in Chatham, Ontario are actually longer in the summer than the days in Orlando, FL. As an extreme, northern areas like Alaska experience periods of 24 hours of “day” in the summer. In areas with fertile soil, are indeed grown.

the onions

1. Long Day Onions: These onions are best suited for areas with more extended daylight periods during the summer, typically requiring 14-16 hours of daylight to form bulbs. They are ideal for higher latitudes and are well-adapted to most of Canada, including Zone 6 areas like Chatham, Ontario. Long day onions thrive in regions like Zone 3-6, making them a common choice across most of Canada and the northern United States.
2. Short Day Onions: These varieties require shorter daylight periods to start forming bulbs, usually around 10-12 hours of light. They are more suited to lower latitude areas with milder winters, typically zones 7 and warmer. Therefore, they are less common in the majority of Canadian gardening zones. These are typically planted in the southern United States,
3. Intermediate (Day-Neutral) Onions: These onions are less sensitive to daylight length and can form bulbs with 12-14 hours of daylight, making them versatile for a range of zones. They can be a good choice for areas that don’t strictly fit into the long day or short day categories. If you were from Windsor, Ontario (Zone 7a), you just might want to pick an intermediate day onion.

The Climate

Chatham, Ontario, experiences the unique climatic conditions of Zone 6b, which include moderately cold winters and long, warm summers. This specific environment is particularly well-suited for long day onion varieties. These onions require more sunlight – typically 14-16 hours of daylight – which is abundant in Chatham during the growing season.

Benefits for Long Day Storage Onions:

1. Extended Daylight Hours: The geographical location of Chatham provides the necessary extended daylight hours during the summer months, essential for long day onions to develop fully.
2. Optimal Temperature Range: Zone 6b offers an ideal temperature range for onion growth. The warm summers promote robust growth, while the cooler temperatures as the season progresses are perfect for curing onions for storage.
3. Soil Conditions: The region’s soil is generally well-draining and fertile, conditions that are conducive to growing healthy onion bulbs with strong root systems.

Growing and Harvesting Tips:

• Planting: For best results, long day onions should be planted in early spring, as soon as the ground is workable.
• Care: Regular watering and weeding are essential, but overwatering should be avoided as it can lead to bulb rot.
• Harvesting: Onions are typically ready for harvest in late summer. The sign of a mature onion is when the tops begin to yellow and fall over.
• Curing: After harvesting, onions should be cured on dry, warm days to prepare them for storage. This process involves drying the outer layers to seal in the flavor and extend shelf life.

Why Storage Onions?

Growing storage onions offers several practical benefits for gardeners and cooks alike. One of the primary advantages is their longevity; these onions, when properly cured and stored, can last for several months, making them an excellent choice for long-term storage. This durability ensures a steady supply of onions throughout the year, reducing the need for frequent grocery store visits.

The process of curing storage onions is crucial for their preservation. It involves drying the outer layers to form a protective wrapping around the bulb, typically done in a shaded, dry, and cool place. This curing can take several weeks, during which the onions develop a papery skin that is key to their preservation.

Once cured, the onions should be stored in a cool, dark, and dry location, ideally at temperatures around 35-40°F. Proper storage conditions are essential to maintain their quality and prevent spoilage. It’s advisable to store them loosely in baskets or mesh bags to ensure good air circulation and to inspect them regularly for signs of spoilage.

In addition to providing convenience and a continuous supply, growing and storing your own onions can be both cost-effective and environmentally friendly. This practice reduces the need for packaging and transportation associated with store-bought onions. Plus, it allows you control over the growing process, potentially reducing the use of harmful chemicals.

Tee’s Plants offers Long Day onions, but by Pre-Order only, since optimal planting dates are around April. (A good while before the sale).

If you want to grow your own, I fully encourage you to. I have had success with a few varieties:

1. Cabernet
2. Walla Walla [Available 2024]
3. Calibra
4. Patterson [Available 2024]
5. Redwing [Available 2024]

Optimally, you should have your seeds sown by the middle of February, and transplant them as soon as the ground can be worked. Frost is okay for onions and they will grow through it.

If you like onion flavor but don’t want to invest the space or effort associated with them, you can try scallions, or chives, instead. Scallions can produce small bulbs comparable in taste to a regular onion, and chives produce the green grass-like onion tasting perennial herb.

Good luck!