Climate-based onion planting guide for Burnaby, British Columbia

When to Plant Onions in Burnaby

Onions are usually easy to fit into the local season in Burnaby. Gardeners typically have enough room to think about harvest goals, not just about whether the crop will finish.

Typical Planting Window

Excellent fit in this climate

Use the planting dates below for onions in Burnaby.

Start indoors January 1
Typical planting window February 26 – March 12
Method Transplant
Typical days to maturity 95–110

Onions are usually started indoors around January 1 and planted outdoors during the normal local window of February 26 to March 12. Most varieties need about 95–110 days to reach maturity once they are in the garden.

Onions are usually easy to grow in Burnaby, and the extra room is most useful for getting a more even finish, steadier sizing, and better keeping quality.

The local margin usually makes this crop comfortable to finish, but uniformity, finish quality, and harvest judgment still separate average results from strong ones.

Best local strategy: Treat maturity as dependable and put your attention on crop quality, consistency, and harvesting in the condition you want.

Can Onions Mature in Burnaby?

Growing degree days measure how much useful warmth typically accumulates during the season. For onions, this helps estimate whether local heat accumulation is usually enough for the crop to reach maturity on time.

Available GDD (base 45) 3053
Typical crop GDD target 1300
Heat margin +1753

From the usual planting window, Burnaby typically provides about 3053 growing degree days for onions. With a typical crop target of 1300, that leaves a heat margin of +1753. That large heat margin means season length is usually not the limiting issue here. The more useful question is how gardeners use that room to improve sizing, finish quality, and harvest timing.

When Is It Too Late to Plant?

If planting later than usual, this table shows how much growing degree day heat is still available from each point in the season. For onions, it is most useful for judging how much freedom you still have to plant for quality, finish, and harvest goals as the season moves along.

Checkpoint Remaining GDD Heat margin Fit vs typical target
Apr 15 2958 +1658 Comfortable
May 1 2837 +1537 Comfortable
May 15 2686 +1386 Comfortable
Jun 1 2456 +1156 Comfortable
Jun 15 2236 +936 Comfortable
Jul 1 1948 +648 Comfortable

How Different Onion Varieties Affect Results

The season in Burnaby usually supports most onion varieties comfortably, which means the more useful decision is what kind of crop you want rather than simply how fast it finishes.

Varieties that often fit well here include:

  • Walla Walla — large and popular, but still best when started early enough to build size
  • Copra — a dependable storage onion with good all-around practicality
  • Redwing — a strong red storage type where the season is reasonably supportive
  • Patterson — a solid keeping onion that wants enough runway to size up well
  • Ailsa Craig — more exposed in shorter seasons because it benefits from a longer finishing run

Best Onion Varieties for Burnaby

Mid-season onion varieties are usually the strongest all-around match in Burnaby. The local season can support onions, so the main choice is usually about bulb size, sweetness, color, and keeping quality.

March 19 local season starts November 10 frost pressure returns
Less heat used 3053 GDD available

Hover or tap the dots to see which recommended varieties use that much local heat.

For Burnaby, start with Redwing and Patterson for onions when you want red storage onions or long-keeping onions. Choose Walla Walla when you want large sweet onions. Look at Ailsa Craig and Copra when you specifically want large exhibition onions or dependable storage onions.

Compare each variety’s heat need and maturity timing against the local frost-free window before choosing what to grow.

Fastest / most cushion

Walla Walla Very early
1100 GDD needed 3053 available before frost
March 19 November 10
Comfortable fit
Why this fit?

Local season fit: Walla Walla leaves about 1953 GDD cushion against the normal Burnaby crop heat estimate.

Best for: large sweet onions.

A large, popular onion that can be rewarding, but still needs an early enough start to build size.

Tradeoff: Needs an early enough start to build size.

Also realistic

Ailsa Craig Late
1400 GDD needed 3053 available before frost
March 19 November 10
Comfortable fit
Why this fit?

Local season fit: Ailsa Craig leaves about 1653 GDD cushion against the normal Burnaby crop heat estimate.

Best for: large exhibition onions.

A large onion that is more exposed in shorter seasons because it benefits from a longer finishing run.

Tradeoff: More exposed in shorter seasons.

Copra Early
1200 GDD needed 3053 available before frost
March 19 November 10
Comfortable fit
Why this fit?

Local season fit: Copra leaves about 1853 GDD cushion against the normal Burnaby crop heat estimate.

Best for: dependable storage onions.

A practical storage onion with good all-around usefulness when started early.

Tradeoff: Still needs enough season to size up.

GDD comparisons are a planning shortcut, not a guarantee. Soil, watering, sowing depth, pests, transplant quality, and harvest goals still affect the final result.

Variety class Typical days to maturity Typical GDD need Local fit
Very early 90–95 1100 Good fit
Early 95–105 1200 Good fit
Mid-season 105–115 1300 Good fit
Late 115–120 1400 Good fit

Main risk: When this crop disappoints here, the problem is usually practical rather than climatic. Timing, steady growth, and harvest stage matter more than season length.

How Frost Affects Planting Dates for Onions in Burnaby

Burnaby usually has about 236 frost-free days, with a typical last spring frost around March 19 and a typical first fall frost around November 10.

Typical last spring frost March 19
Typical first fall frost November 10
Typical frost-free days 236
Minimum safe temperature 28°F / -2 °C

Onions are generally lightly frost tolerant and temperatures below about 28°F ( -2 °C) can slow growth or damage plants.

Onions are usually tolerant enough of cool conditions that frost dates act more like planning markers than hard limits. In practice, timing and steady early growth matter more than avoiding every light frost.

When this crop disappoints in Burnaby, the issue is usually management rather than climate fit. Timing, consistency, and harvest decisions matter more than season length.

In Burnaby, the local season usually gives onions plenty of breathing room when planting happens around February 26. For a better local margin, gardeners usually do best in south-facing walls, sheltered gardens, raised beds, and sunnier urban lots. Cooler spots like low spots, exposed sites, and shadier yards often make timing tighter. For onions, the best local sites often help the crop get moving earlier and make timing a little more forgiving.

Set up onions for sizing, watering, and storage

The biggest gains usually come from better planting setup, steady moisture, good sizing, and clean harvest handling rather than season extension.

Soil and planting setup

For storage crops, the best gains usually come from strong early growth and a clean finish.

Moisture control

Consistent watering helps sizing and reduces stress during key growth stages.

Harvest and storage

Once the crop fits the season, harvest handling and curing become part of the result.

Recommendations are based on the local growing margin for this crop. As an Amazon Associate, we may earn from qualifying purchases.

For a broader local overview, see the Burnaby planting guide. You can also use the Growing Degree Day Planner to test planting dates and crop timing.