Short-Season Variety Finder
A seed packet gives you “days to maturity”. The real question is whether that number fits your season. Pick your city and this tool works out your frost-free days, then gives you the maximum days-to-maturity to shop for, crop by crop.
It depends on your frost-free season length — the days between your last spring frost and first fall frost, which runs from roughly 95 days in Prince Albert to over 200 days on the British Columbia coast (Environment and Climate Change Canada climate normals). Pick your city and this tool subtracts a safety margin from your season and gives you, for each crop, the maximum days-to-maturity to look for on the seed packet, and which crops must be started indoors to have any chance.
Pick your city to see your thresholds.
How the maths works
1. Your frost-free season = the days between your average last spring frost and first fall frost (ECCC climate normals).
2. Subtract a 10-day margin for a cold spring, slow soil, or a frost that arrives earlier than average.
3. What's left is the maximum “days to maturity” you can afford on a packet.
4. Transplanted crops count their days from transplant — the indoor head start is what makes them possible at all, it doesn't add to your season.
When to Order — the Canadian Seed Calendar
The threshold above tells you what to shop for. This tells you by when. Canadian seed houses run on a tight winter schedule, and the varieties that sell out first are exactly the short-season ones this tool sends you looking for.
Mid-December — catalogues land
Print and online catalogues go out from about mid-December. Nothing is urgent yet, and this is the good moment to work out your thresholds and write a list rather than shop.
January — the ordering peak
The busiest ordering month, and the one where short-season and heirloom varieties start going out of stock. If a specific early tomato or a named cultivar matters to you, this is when to place that order — not when you are ready to sow it.
February — the seed has to be in hand
The longest indoor head starts begin now: leeks and celery go under lights about ten weeks before your last frost, peppers, onions and eggplant about eight. In the mildest coastal cities that means late December or early January, not February.
March onward — what is left
Direct-sown crops are still easy to buy: beans, carrots, beets, radishes, lettuce and squash are stocked deep and restocked. What you will struggle to find late is the named short-season cultivar, which is the thing a short season actually depends on.
This is the general seasonal pattern reported by Canadian seed houses and gardening press, not something this site has measured. Your own sowing dates — which are measured, from ECCC frost normals — are the ones in the tool above.
Reading a Seed Catalogue — Four Traps
The days-to-maturity number is the one the threshold above is measured against, and it is less straightforward than it looks.
Two different clocks
This is the big one. For a transplanted crop — tomatoes, peppers, brassicas — catalogue days-to-maturity is counted from the day the plant goes in the ground, not from sowing. For a direct-sown crop — carrots, beans, radishes — it is counted from sowing. So a tomato at 60 days and a carrot at 70 days are not 10 days apart; the tomato has six weeks of indoor growing behind it that the number never mentions. Comparing the two figures directly is meaningless. The threshold above already handles this, which is why tender transplants and direct-sown roots can share one table.
The same variety, different numbers
Days-to-maturity is not a fixed property of a cultivar. An audit of this site's own pages found "Early Girl" published as 52, 54, 55, 57 and 62 days and "Sub-Arctic Plenty" as 45, 55 and 62 — because suppliers trial in different places and genuinely get different results. Use the figure printed on the packet you are actually holding, and treat a difference of a few days between catalogues as normal rather than as an error.
It assumes a good year
The number is what the crop did under the supplier's trial conditions. A cool cloudy summer adds days to it, sometimes a week or more on heat-loving crops. That is the reason the threshold above subtracts a margin from your frost-free season instead of spending all of it — a variety that fits exactly on paper does not fit in a cold year.
Hybrid or open-pollinated
A catalogue marks hybrids F1. Hybrids are often earlier and more uniform, which matters in a short season, but their saved seed will not come true next year. Open-pollinated and heirloom varieties can be saved and re-sown. Neither is better; it is only worth deciding in January, because it changes what you buy rather than what you do in August.
Common questions
What counts as a “short season” in Canada?
In practice, any frost-free season under about 120 days. That covers much of the Prairies, northern Ontario and Quebec, the northern BC interior, and the territories. Prince Albert runs around 95 days; Winnipeg and Calgary around 115–120; Toronto approaches 195, and the BC coast is well over 200. That spread is exactly why American gardening advice — or even southern Ontario advice — fails on the Prairies: the crop is the same, but the variety has to be different.
Are “days to maturity” counted from sowing or from transplant?
It depends on the crop, and this trips a lot of people up. For direct-sown crops — carrots, beans, radishes, lettuce — the count starts at sowing. For transplanted crops like tomatoes, peppers and eggplant, the packet almost always counts from transplant into the garden, not from the indoor sowing date. That's why a 65-day tomato is not ready 65 days after you sowed it in March: you add the indoor head-start weeks on top. This tool uses the same convention and compares the packet figure against your outdoor window.
Why subtract a 10-day margin?
Because packet days assume good conditions. A cold spring, slow-warming soil, a grey week, or a checked transplant easily adds a week or two to the real timetable — and the frost dates themselves are averages, so in half of all years your frost arrives earlier than normal. A 10-day margin is cautious without being pessimistic. If you garden on an exposed site or at elevation, allow more.
Why doesn't the tool list days for each variety?
Because that figure is not reliable enough to publish as data. A variety's days-to-maturity genuinely varies between seed suppliers and with growing conditions, and an audit of our own guides found the same variety quoted with different figures in different places. Rather than pick one number arbitrarily and present it as authoritative, the tool gives you the threshold to stay under and lets you read the real figure off the packet in your hand. That's also more useful — the threshold works against any catalogue.
How do I stretch a short season?
Three levers, easiest first. Start seed indoors — that is what makes tomatoes and peppers possible on the Prairies at all. Protect both ends of the season: frost blankets, low tunnels, cloches and cold frames comfortably buy two to four weeks at each end. And warm the soil in spring with black plastic or clear sheeting before planting heat-loving crops. Combined, those often add a usable month — enough to bring a variety inside your window that otherwise wouldn't fit.
Can I trust the average frost date?
It's an average, not a guarantee — in roughly half of years frost arrives earlier. Use it to plan what seed to buy, then watch the actual forecast as the season closes. Our Frost Tonight tool reads the coming night's low for your city, which is the right question once harvest is close.
Related tools
Frost dates: Environment and Climate Change Canada climate normals. Per-crop days-to-maturity are typical direct-sow figures, kept consistent with our other tools; per-variety figures vary between seed suppliers — always read the packet.