Nunavut’s Arctic summer sun barely sets, which is exactly why the answer here is narrow. At Rankin Inlet, the territory’s reference point at 62.82 degrees north, the longest day of the year delivers 19 hours and 41 minutes of daylight. That single number rules out almost every onion variety sold in North America and leaves exactly one documented match: Redwing, a long-day type rated for 43 to 65 degrees north.
The short answer for Nunavut
Onions don’t bulb because the weather warms up. They bulb because of day length, full stop. A short-day onion switches from growing leaves to building a bulb once daylight reaches roughly 12 hours; an intermediate-day type waits for something closer to 12 to 14 hours; a long-day type holds off until 14 to 16 hours. Rankin Inlet blows past all three thresholds by early summer, and by the solstice it’s sitting at 19 hours and 41 minutes, a level that no catalog variety is even rated to require.
That puts Nunavut squarely in long-day territory, but not just any long-day onion. Most long-day varieties are bred for the northern United States and southern Canada, places that top out around 50 to 55 degrees north on the longest summer days. Nunavut needs something bred to handle a photoperiod that stretches well past that, without bulbing so early in the season that the plant hasn’t built enough leaf mass to feed a decent-sized bulb.
Among the 31 varieties documented for this site, only one carries a published range that reaches 62.82 degrees north: Redwing, rated from 43 to 65 degrees north. That upper limit matters. It means Redwing has been selected specifically to keep growing leaves through the long Arctic daylight window before it responds to the day-length cue and starts building a bulb, rather than triggering prematurely the way a variety bred for Ohio or Michigan would.
This isn’t a case of picking a favorite from a long list. For a gardener working the short, intense growing season around Rankin Inlet or a comparable Kivalliq community, Redwing is the variety the data actually supports. Everything else on the documented list carries a published range that stops well south of where Nunavut sits.
What will not work here
The mechanism matters more than the label. Under close to 20 hours of daylight, a short-day or intermediate-day onion doesn’t fail to bulb, it bulbs almost immediately, often within weeks of germination and while the plant is still small. The result is a marble-sized onion instead of a full one, because whatever leaf growth the plant managed before the day-length trigger fired is all the bulb ever gets to draw on. That’s a variety mismatch, not a feeding or watering mistake.
Short-day and intermediate-day varieties
- Candy (intermediate-day, 33-40N), hits its bulbing trigger almost instantly under Arctic daylight, leaving a tiny bulb
- Cabernet (intermediate-day, 35-45N), same premature-bulbing problem, plant never fills out first
- Calibra (intermediate-day, 35-45N), bulbs too early for the leaf mass to support size
- Elsye (intermediate-day, 32-45N), rated for a photoperiod far shorter than Rankin Inlet’s
- Expression (intermediate-day, 32-45N), same issue, small bulb guaranteed
- Monastrell (intermediate-day, 35-46N), day-length trigger fires long before the plant matures
- Red Long of Florence (intermediate-day, 38-50N), bred for a much lower daylight ceiling
- Red Long of Tropea (intermediate-day, 35-48N), same mismatch as the other Tropea-type onions
- Scout (intermediate-day, 32-46N), trigger point reached almost immediately here
- Sierra Blanca (intermediate-day, 32-45N), same premature-bulb outcome
- Gabriella (short-day, 20-35N, no page of its own on this site), bulbs within days of the day-length threshold
- Madalyn (short-day, 20-35N, no page of its own on this site), far too aggressive a trigger for this latitude
- Red Rock (short-day, 30-36N, no page of its own on this site), same short-day problem
- Red Sensation (short-day, 25-35N), bulbs immediately, stays small
- Texas Grano 1015Y (short-day, 25-35N), bred for a daylight ceiling half of Rankin Inlet’s
- Vidora (short-day, 25-35N), same mismatch
- White Castle (short-day, 30-38N, no page of its own on this site), bulbs too soon for any real size
Long-day varieties not rated this far north
These are true long-day onions, but their published ranges stop south of 62.82 degrees. That gap usually reflects a growing season that isn’t built for the compressed, intense Arctic summer rather than the day-length math alone.
- Ailsa Craig (long-day, 38-60N), range ends two degrees short of Rankin Inlet
- Walla Walla Sweet (long-day, 35-55N), not documented past 55N
- Rossa di Milano (long-day, 38-50N), rated for a much shorter Arctic-style day than Nunavut delivers
- Patterson (long-day, 38-55N), stops well south of Rankin Inlet
- Barolo (long-day, 38-55N), same southern ceiling
- Blush (long-day, 38-55N), not rated for this photoperiod
- Bridger (long-day, 35-50N), range far short of 62.82N
- Frontier (long-day, 40-50N), not bred for this latitude
- New York Early (long-day, 38-50N), southern long-day, unsuited here
- Safrane (long-day, 42-50N), falls short by more than 12 degrees
- Talon (long-day, 42-50N), same gap
- Powell (long-day, 43-47N), closest of this group but still well south
- Red Carpet (long-day, 40-45N), not documented anywhere near this latitude
What changes across Nunavut
Rankin Inlet, the figures above are drawn from that station, sits in the Kivalliq region on the western shore of Hudson Bay. It’s a reasonable middle point for southern Nunavut, but the territory itself runs much farther in both directions, and the advice above bends the farther you go from that reference point.
South of Rankin Inlet, communities closer to the Manitoba border see slightly shorter summer days, which still comfortably clears every bulbing threshold and keeps Redwing the right call. North of it, the picture shifts fast. Past the Arctic Circle, at 66 degrees 33 minutes north, the sun doesn’t set at all for stretches of the summer, meaning communities in the High Arctic experience continuous daylight rather than a defined “longest day” figure.
| Region | Summer daylight pattern | What it changes |
|---|---|---|
| Rankin Inlet (62.82N) | 19h41 on the longest day | Redwing’s 43-65N range covers this latitude comfortably |
| North of the Arctic Circle (66°33’N and beyond) | Continuous daylight for weeks in midsummer | Exceeds even Redwing’s documented 65N ceiling; no variety on this list is confirmed that far north |
That table isn’t a footnote. A gardener in a High Arctic hamlet like Grise Fiord or Resolute is gardening past the edge of what any catalog variety has been tested against, which means results there are far less predictable than in Rankin Inlet or the southern Kivalliq communities.
Checking this against your own garden
A single station reading and a single variety recommendation can’t stand in for every yard in a territory this size. Before ordering seed, run through a short list of checks specific to where you actually garden.
- Look up your own latitude if you’re not near Rankin Inlet, especially if you’re south toward the Manitoba border or north past the Arctic Circle
- Confirm your local frost-free window, since Nunavut’s growing season is short even by Canadian standards and varies by community
- Contact your local agricultural extension service or community greenhouse program for planting dates suited to your specific hamlet
- Ask whether anyone locally has grown Redwing or another long-day onion successfully, since real-world results at this latitude are still thin
- Check whether a cold frame, hoop house, or community greenhouse is available, since starting onions indoors under supplemental light is standard practice this far north