Canada's Premium Cannabis Seed Bank | Discreet Shipping
Canada's Premium Cannabis Seed Bank | Discreet Shipping
Four plants. That is what Canadian law gives you — four cannabis plants per household, grown from legally purchased seeds. In California, four plants is a warm-up. In Canada, four plants is your entire season, and the country’s climate makes every one of them count.
The outdoor cannabis growing season in Canada is not like anywhere else. Most of this country gets its last spring frost sometime in May and its first fall frost by mid-September or early October. Everything you grow has to happen inside that window. Pick a strain that needs 12 weeks of flowering and you will spend October watching unfinished buds get hammered by cold rain and mould. Pick one that finishes in 7 weeks and you are pulling jars off the drying rack while your neighbours’ gardens are still going.
This guide is built around that reality: short seasons, damp falls, and the annual race against frost. Lighthouse Genetics is based in Canada, where short seasons are the norm for most growers.
Under the Cannabis Act, every Canadian household can grow up to four plants, and that includes your yard. The seeds have to come from a legal source.
Provinces add their own rules on top, and for an outdoor grower they matter. Quebec bans home growing entirely. Manitoba (since May 2025) allows home growing indoors only, and Newfoundland and Labrador only inside a dwelling or an enclosed structure on the property, not in the open yard. New Brunswick and Prince Edward Island require outdoor plants to sit behind a locked enclosure at least 1.52 metres (5 feet) high, and British Columbia, PEI and Newfoundland and Labrador require plants to be out of view from public places like streets and parks.
Most provinces set the age at 19 (18 in Alberta). Some provinces also set rules on where seeds and seedlings must come from, so check your provincial government’s cannabis page before you plant.
If you rent, check your lease. Landlords and condo boards can restrict cultivation regardless of what federal law allows.
With only four spots available, choosing the wrong strain is expensive. Not in dollars — in time. A failed outdoor plant means you wasted one quarter of your legal growing capacity on something that never finished. That makes strain selection one of the biggest decisions when you are growing cannabis outdoors in Canada.
Frost is the hard edge of the season. Young seedlings die in a frost, and while big, mature plants can shrug off a light one near 0°C (32°F), a moderate freeze of about -2 to -4°C (25 to 28°F) can damage the foliage (University of Vermont Extension). When you are growing cannabis outdoors in Canada, your usable season is the gap between your last spring frost and your first fall frost:
| Region | Last Spring Frost | First Fall Frost | Usable Season |
|---|---|---|---|
| Coastal BC (Vancouver, Victoria) | Mid-March – early April | Early – mid November | 7-8 months |
| Interior BC (Kamloops, Kelowna) | Late April – mid-May | Late September – mid-October | 4.5-5.5 months |
| Southern Alberta (Calgary) | Late May | Mid September | ~4 months |
| Prairies (Edmonton, Saskatoon, Winnipeg) | Mid–Late May | Mid–Late September | About 3.5-4 months |
| Southern Ontario (Toronto, Hamilton, Niagara) | Late April – mid-May | Early–Mid October | 5-5.5 months |
| Northern Ontario (Sudbury, North Bay, Sault Ste. Marie) | Mid–Late May | Late September – early October | About 4-4.5 months |
| Atlantic Canada (Halifax, Fredericton, St. John’s) | Mid–Late May | Late September – October | 4-5.5 months |
| Northern Canada (Whitehorse, Yellowknife) | Late May – early June | Late August – mid-September | About 2.5-4 months |
These are average frost dates from Environment and Climate Change Canada’s 1981–2010 Canadian Climate Normals, mostly at airport stations; city centres and lakeshores run a little milder. They are averages, so frost comes earlier than the listed date in roughly half of years. In a bad year, a late frost in early June or an early freeze in mid-September cuts weeks off your window. The growers who consistently succeed plan for the short end of the range.
The country breaks into three tiers. Tier 1 is coastal BC — the longest season, the mildest climate, almost anything works. Tier 2 is southern Ontario, interior BC, and Atlantic Canada — roughly four to five and a half months, enough for fast-flowering photoperiod strains and autoflowers. Tier 3 is the prairies, northern Ontario, and the territories — about four and a half months or less, where autoflowers are the safe choice.
Coastal BC — Vancouver, Victoria, the Island — has Canada’s mildest growing climate. You can put plants outside in April, and long-flowering sativas that would never finish anywhere else in the country can finish before the first frost, which on average doesn’t arrive until early to mid-November. The main risk is not cold but rain. Fall rain soaks buds and invites mould, so even with a long season, cover your plants or choose strains with airier buds that finish before October’s rains.
Interior BC is a different grow. The Okanagan and Kamloops corridor gets hot, dry summers — excellent for cannabis — but fall arrives weeks earlier than on the coast. Late-summer wildfire smoke is another wildcard: thick smoke cuts the sunlight reaching your plants, though research in BC found light haze can actually help photosynthesis by scattering light. Stick to the fastest-flowering strains and check each against your local first-frost date, or run autoflowers to sidestep the timing risk entirely.
Alberta is short-season territory. Calgary averages about 117 frost-free days, with the last frost around May 21 and the first around September 16. Planting out in early June, after the average last frost, leaves you about three and a half months. Chinook winds in spring can push temperatures to 15°C (59°F) in March, tempting you to plant early. Do not fall for it. A late-May frost can kill young transplants.
The upside: Alberta is dry. Calgary’s afternoon humidity in August and September averages about 45%, against nearly 60% in Toronto, and fall rain is light, so bud rot is less of a threat than in Ontario or the Maritimes. Your main enemy is time, not moisture. Southern Alberta sits in Canada’s hail belt — a summer hailstorm can shred a plant in minutes. If you can rig a cover, do it. Autoflowers are the practical choice for most Alberta outdoor growers.
Saskatchewan is flat, windy, and short-season. Prairie wind can snap branches on tall, unprotected plants, so stake or cage them. The good news is that Saskatchewan summers are hot and sunny with low humidity, which cannabis loves and mould does not. Your limiting factor is the calendar: plant in late May, harvest by mid-September, and run autoflowers to make the math work.
Manitoba has allowed home growing since May 1, 2025, but the Manitoba government requires plants to be grown indoors. Outdoor growing is still not allowed there, so the outdoor advice in this guide doesn’t apply in Manitoba. For reference, Winnipeg’s frost-free season is similar to Saskatchewan’s: about four months, from late May to late September.
Southern Ontario — everything south of Barrie — is some of the best territory for growing cannabis outdoors in Canada. The frost-free season runs from late April or mid-May through early to mid-October, five months or better. That is enough for photoperiod strains listed at about eight weeks of flowering; longer ones run into mid-October and the first frosts.
The catch is September. Nights get cool and mornings are damp (Toronto’s average early-morning humidity in September is close to 90%), right when your plants are deep into flower, and that is when botrytis moves in. If you are growing photoperiod strains in Ontario, favour airier bud structure and faster finishers — or finish before September turns ugly by running autoflowers alongside your photoperiod plants.
Northern Ontario — Sudbury, North Bay, Sault Ste. Marie, Thunder Bay — is a different climate entirely. Sudbury and North Bay average about 135 frost-free days (four and a half months), from mid-May to the end of September. Treat it like the prairies: autoflowers as the primary option, and the fastest-finishing feminized strains if you want to push it.
Home growing is illegal in Quebec. The province bans possessing or growing cannabis plants for personal use, with fines of $250 to $750, and the Supreme Court of Canada upheld that ban in 2023. The outdoor advice in this guide doesn’t apply in Quebec unless that law changes.
New Brunswick allows outdoor plants only behind a locked enclosure at least 1.52 metres (5 feet) high. The season is a decent length — roughly late May through late September — but the Bay of Fundy and the Atlantic coast bring fog: Saint John averages over 90 fog days a year. Moisture is the main threat, so choose strains with airier bud structures over very dense ones. Autoflowers sown in late May usually finish in August, ahead of the worst of the fall damp.
Nova Scotia is cool, humid, and windy — especially along the coast. Halifax averages well over 100 fog days a year. The season length is reasonable (roughly five months around Halifax) but the moisture is relentless. Pick strains that finish early and have airier buds; dense, late-finishing buds sitting in wet fall air are the ones most at risk. Coastal growers should also stake plants against the wind and consider a sheltered spot — a south-facing wall or fence line that blocks the prevailing ocean breeze.
PEI requires outdoor plants to sit behind a locked enclosure at least 1.52 metres (5 feet) high and out of view from public places. The island is small, flat, and surrounded by water. Wind and salt spray are constant near the coast. The season is moderate, a little longer than New Brunswick’s, but the maritime air keeps summers cool (Charlottetown’s July afternoons average about 23°C (73°F), against about 27°C (81°F) in Toronto). Fast autoflowers that finish by late summer get done before the fall damp. Grow in a sheltered spot and expect to fight moisture, not heat.
Newfoundland and Labrador’s cannabis regulations allow home growing only inside a dwelling or an enclosed structure on the property, not in the open yard, so open-air outdoor growing isn’t allowed here. The climate would be hard on it anyway: St. John’s averages about 120 fog days a year, one of the highest counts of any Canadian city, and Happy Valley-Goose Bay in Labrador gets about three and a half months without frost.
If you are growing above the 60th parallel, your frost-free season is extremely short: Whitehorse averages only about 80 frost-free days. Midsummer days run 19 to 20 hours in Whitehorse and Yellowknife, and the sun never sets at all further north. Autoflowers don’t mind, because they flower on age, not day length. Photoperiod plants are the problem: the days don’t shorten enough to trigger them until about early September, after Whitehorse’s average first frost.
Check your territory’s rules before you plant outdoors. Autoflowers are the only practical choice this far north, and even they are tight. Choose the fastest you can find, such as AK-59 Autoflower (about 8 to 10 weeks from seed to harvest), and leave margin: autoflowering hemp in a University of Wisconsin field trial was cut about 12 weeks after sowing (seven weeks into flower, as the trial set it).
If you are growing cannabis outdoors in Canada, start your photoperiod seeds indoors. Dropping a seed directly into the ground on the Victoria Day long weekend and hoping for a finished harvest by early October is a gamble you do not need to take.
Start seeds inside about four to six weeks before you plan to transplant: around mid-April for a mid-to-late-May move outdoors in southern Ontario. A south-facing window works. A basic LED grow light works better. Grow your seedlings in small pots for four to six weeks, then transplant outside once the danger of frost has passed and the soil has warmed to about 10°C (50°F). That head start gives your plants a month of growth before they touch outdoor soil — and in a country where every week matters, that month is the difference between finishing and not finishing.
If you have not germinated seeds before, we have a step-by-step walkthrough: A Simple Guide to Germinating Cannabis Seeds.
Autoflowers are the exception. They dislike transplant stress, so sow them straight into their final spot in late May, after the last frost.
If you are in Tier 3 — the prairies, northern Ontario, the territories — autoflowers are the safe choice. Photoperiod plants need shortened autumn days to trigger flowering, and in these regions that comes so late that even fast ones finish close to or after the average first frost.
If you are in Tier 2, you have a real choice. Feminized photoperiod strains work outdoors in southern Ontario as long as you choose varieties that flower quickly. The plants veg naturally under the long summer days and usually start flowering in early to mid-August, once the days shorten past their strain’s trigger point (plants in a University of Wisconsin field trial at the same latitude were flowering by early August). A strain listed at 7 to 8 weeks of flowering then finishes around late September to early October; a 9-week strain runs into mid-October, so check it against your first fall frost date.
One option is to run both. Two autoflowers and two feminized plants. The autos come down in August, giving you something to smoke while the photoperiod plants finish through September. Smart use of that four-plant limit.
We wrote a full breakdown of the two seed types: Autoflower vs Feminized Seeds: Which Should You Grow?
If you are growing cannabis outdoors in Canada, strain choice is where your season is won or lost. The strains below are picked for one reason: they finish in time. They are organized by how fast they get the job done, with autoflowers and feminized mixed together — because outdoors in Canada, finishing speed matters more than seed type. The times below are the breeders’ listed flowering times unless marked “from seed” (an autoflower’s seed-to-harvest figure includes its first three or four weeks of growth); outdoors, plan on longer.
AK-59 Autoflower runs about 8 to 10 weeks from seed to harvest, temperate climate rated, easy difficulty. If you are growing north of Sudbury or anywhere in Tier 3, this is where you start. Super Skunk Feminized flowers in 6 to 7 weeks, as quick as any feminized option we carry. If you want to gamble on a photoperiod plant on the prairies, this is the one to pick, but even it usually finishes after the average first frost there, so be ready to cover it on cold nights or chop early.
California Hash Plant Feminized finishes flowering in about 7 weeks, and that fast finish is the real advantage for a short season; its buds are tight and compact, though, so watch it closely in a damp fall.
Green Crack Autoflower is listed at about 9 to 10 weeks from seed and is a hybrid that leans slightly sativa (55/45). Kush XL Autoflower is another fast auto, but indica-dominant. Both are temperate-rated and rated easy — good picks if you are on your first grow.
Afghani Feminized flowers in 7 to 8 weeks. Its buds are dense and can be prone to mould, so it suits the drier prairies or interior BC better than a damp Ontario or Atlantic fall. Sugar Black Rose Feminized runs a similar window, about 7 to 8 weeks, and is listed for a mid-September outdoor harvest; in humid maritime or Great Lakes climates, keep air moving through the canopy late in flower.
White Widow Autoflower is listed at about 8 to 9 weeks from seed, stays compact (70 to 80 cm, about 28 to 31 inches), and is rated for temperate climates. Fat Bastard Autoflower (listed at 8 to 10 weeks from seed to harvest) is another strong option — also rated for temperate climates and easy difficulty.
Grape Skunk Feminized needs 8 to 10 weeks of flowering. It is a Lighthouse Genetics original, bred by Macs_Budz here in Canada. Continental climate rated, easy difficulty, and outdoors in temperate climates it finishes by early to mid-October, which suits southern Ontario or coastal BC.
Northern Lights Skunk Feminized flowers in 8 to 9 weeks, is listed for a Mediterranean or temperate season and rated easy, and gives up to about 450 g (16 oz) per plant outdoors, with an October harvest. Alaskan Thunder Fuck Feminized runs 8 to 9 weeks. It has a northern reputation, but no published trial has tested its cold tolerance, so judge it on timing like any other strain.
Avoid anything that needs more than 10 weeks of flowering unless you are in coastal BC. A Colombian Gold, with its 10 to 14 week flowering time, tropical climate rating and late-November outdoor finish, has no business being planted outdoors in Saskatoon.
The picks above are hand-chosen, so we also ran every photoperiod and autoflower we stock with a clear listed time (61 and 28) against the season table. Photoperiods start flowering on August 8, the middle of the early-to-mid-August start described above, and run their listed flowering weeks. Autoflowers are sown on May 31 (June 10 in the territories) and run their listed seed-to-harvest weeks. Each region gets the early end of its first-frost range, because that is the end to plan for. Where two numbers appear, the first counts strains by the slow end of their listed range and the second by the fast end.
| Tier and Region | Plan for First Frost By | Photoperiods That Finish (of 61) | Autoflowers That Finish (of 28) |
|---|---|---|---|
| Tier 1: Coastal BC | November 1 | 60–61 | 28 |
| Tier 2: Southern Ontario | October 1 | 2–9 | 28 |
| Tier 2: Interior BC, Atlantic Canada | September 21 | 0–2 | 28 |
| Tier 3: Northern Ontario | September 21 | 0–2 | 28 |
| Tier 3: Alberta, Saskatchewan | September 15 | 0 | 28 |
| Tier 3: Territories | August 21 | 0 | 15–26 |
By their listed flowering times, most of the photoperiods we carry are Tier 1 plants. 56 of the 61 list 9 weeks or more at the slow end, and a 9-week strain started on August 8 finishes October 10. In southern Ontario only California Hash Plant and Super Skunk, at 6 to 7 weeks, fit at the slow end; seven more, such as Skunk Feminized and Sugar Black Rose, fit only at the fast end. The margin is thin, though: an 8-week strain finishes October 3, two days past that early frost date, so the 8-to-10-week picks above, such as Grape Skunk, are a bet on a frost that holds off until mid-October.
All 28 autoflowers fit from southern Ontario to the prairies, even at the 12 weeks the Wisconsin field trial took. In the territories, the 15 listed at 10 weeks or less from seed fit, including AK-59 and Gelato Autoflower, but only just: sown June 10, a 10-week auto finishes August 19, two days before the frost date, and at the trial’s 12 weeks none would make it.
Read the photoperiod counts as a best case. Our product pages give flowering time as weeks indoors, under a switch to 12 hours of light; outdoors the plant waits on the shortening days and can run longer. Super Skunk, for one, lists 6 to 7 weeks indoors but a mid-October outdoor harvest in the Northern Hemisphere. In Tier 3 the days also shorten later, so flowering there starts after August 8 and those counts are a ceiling. If a strain only fits at the fast end of its range, plan to cover it on cold nights or harvest a little early.
Browse all autoflower seeds | Browse all feminized seeds
If your grow survives until September, congratulations — now the hard part of growing cannabis outdoors in Canada starts.
Nights get cold. Dew settles on the plants every morning. This is when botrytis (grey mould, or bud rot) moves in. It thrives in cool, damp weather, and rain while buds are ripening is what triggers big outbreaks in hemp fields, according to the Pacific Northwest Plant Disease Management Handbook. Once a bud is infected it can’t be saved, so prevention is everything.
What actually works:
If you want to skip the September stress entirely, grow autoflowers. Our fast autos are listed at about 8 to 10 weeks from seed; in a field trial, autoflowering hemp was cut about 12 weeks after sowing. Sown in late May, that still points to a harvest in August, so you dry and cure while September’s damp does its worst to everyone else’s plants.
This calendar is based on southern Ontario. Coastal BC growers can start a month earlier. Prairie and northern growers, push everything two to three weeks later and lean on autoflowers.
| Month | What Is Happening |
|---|---|
| April | Germinate seeds indoors. Grow seedlings under a window or basic light. Build root systems in small pots. |
| May | Harden off seedlings — outside for a few hours daily, increasing over a week. Transplant after last frost (mid to late May). Direct-sow autoflowers after the long weekend. |
| June | Vegetative growth takes off. 15+ hours of daylight drives rapid development. Top and train photoperiod plants. Autoflowers planted in late May start flowering in late June or early July. |
| July | Peak veg for photoperiod plants — they drink heavily. First autoflower buds are fattening. Watch for pests (caterpillars, aphids, spider mites). Some growers start a second, smaller round of autos by early July for a late-September harvest; it’s untested, so check the strain’s listed seed-to-harvest time against your first frost date. |
| August | Photoperiod plants start flowering in early to mid-August. First autoflower harvest. Keep feeding nitrogen through early flower; ease off only in the last few weeks. |
| September | Mould watch. Defoliate, knock dew off gently, cover if possible. Second autoflower harvest. Late-month: 8-week strains are approaching harvest — check trichomes with a loupe. |
| October | Harvest photoperiod plants before mid-month. Watch the forecast daily — chop before hard frost. Dry at 15-20°C (59-68°F) and about 50-55% humidity; outdoor buds take two weeks or more. Patience during the cure makes better flower than anything you did during the grow. |
For a deeper walkthrough from seed to harvest, see our full growing guide. And if you want to squeeze more out of your four plants, maximizing yield in cannabis covers the training and feeding techniques that make the biggest difference outdoors.
Growing cannabis outdoors in Canada is a shorter, harder game than growing in warmer climates. But it is a game you can win. The growers who do well up here are the ones who match their strains to their frost dates, start seeds indoors, and respect what September can do to unfinished buds.
Know your season. Pick strains that finish inside it. Give them a head start indoors. And if you are anywhere north of Barrie, make peace with autoflowers — they were built for this.
Shop All Seeds | Autoflower vs Feminized Guide | Best Autoflowers for Beginners | Full Growing Guide
After the last frost — mid to late May for southern Ontario. The Victoria Day weekend is a handy marker. But start your seeds indoors 4 to 6 weeks before that. For photoperiod plants, a seedling with a month of indoor growth behind it gets a real head start on a short Canadian season. Autoflowers are the exception: sow them straight into their final spot.
Photoperiod plants in southern Ontario usually start flowering in early to mid-August, once the nights get long enough for their strain. In a University of Wisconsin field trial at about the same latitude, the earliest seed-grown hemp varieties were half in flower by August 3 and the rest by the end of August. Autoflowers ignore day length: in the same trial they started flowering about five to six weeks after sowing.
Only if you choose the fastest-flowering options and accept the risk. Super Skunk at 6-7 weeks flowering is about the limit. Autoflowers are the safer prairie choice because a three-and-a-half to four-month outdoor window does not leave room for error with photoperiod timing.
It depends where you are growing cannabis outdoors in Canada. Bud rot needs cool, damp weather and rain while buds ripen, so in the humid east (Ontario and Atlantic Canada) mould is often the bigger threat. On the drier prairies, the season simply runs out and frost ends it. Either way, the fix is the same: grow strains that finish before your weather turns.
Outdoor yields swing too widely with strain, sun, soil and season to promise a number. In a University of Wisconsin hemp trial, photoperiod plants started indoors in May finished the season about eight times heavier (whole dried plants, stems included) than autoflowers sown outdoors in late June. It wasn’t a like-for-like test, since the photoperiods had a six-week head start and more room, but it shows how much bigger a full-season plant can get. With only four spots, that matters. Among the heaviest yielders in our catalog, the breeder lists Big Bud Feminized at 800 to 1,200 g (about 28 to 42 oz) per plant outdoors; treat that as a best case, not a promise.
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