Canada's Premium Cannabis Seed Bank | Discreet Shipping
Canada's Premium Cannabis Seed Bank | Discreet Shipping
Not every grower has the luxury of a long, lazy season. Maybe your outdoor summer is short and the frost comes early. Maybe you’re indoors and you’d rather harvest in two months than four. Maybe you just don’t have the patience to babysit a plant until Halloween. Whatever the reason, fast flowering cannabis exists for exactly this — strains bred to race from seed to jar in weeks instead of dragging on for months.
This is a rundown of the quickest-finishing seeds we carry, split into the two ways a plant can finish fast: autoflowers that sprint through their whole life on a fixed internal clock, and short-flowering photoperiod strains that wrap up their bloom faster than the average. Every flowering time below is pulled straight from our own catalog data, not rounded down to sound impressive. If you want the broadest selection of fast flowering cannabis in one place, the autoflowers are where you’ll find it.
There are two different things people mean by fast flowering cannabis, and the difference matters when you’re choosing seeds.
The first is autoflowers. These carry Cannabis ruderalis genetics, which let them flower based on age rather than the light schedule. A photoperiod plant only starts blooming when nights get long (or you flip the lights to 12/12); an autoflower just starts on its own after a few weeks no matter what the light does. That fixed clock is why autoflowers finish so fast — there’s no long vegetative wait, so the whole grow is often done in around two months from sprout.
The second is a short-flowering photoperiod — a regular feminized strain whose bloom phase is simply shorter than average. Most photoperiod strains in our catalog flower in 8–10 weeks; the fast ones sit at the bottom of that range, while long-season sativas and hazes can run well past it. Indica-leaning plants tend to finish soonest. For a short outdoor season, picking a fast flowering cannabis photoperiod can be the difference between a ripe harvest and a frost-killed one.
Here’s how the two approaches to fast flowering cannabis stack up at a glance:
| Factor | Autoflowers | Short-Flowering Photoperiods |
|---|---|---|
| Total time from seed | ~2 months | 3–4 months |
| Flowers based on | Age (fixed clock) | Light schedule |
| Plant size | Compact | Full size |
| Yield per plant | Smaller | Larger |
| Multiple harvests/year outdoors | Yes | No |
| Best for | Speed, short seasons, beginners | Yield, training, cloning |
Neither approach is “better” — it’s a trade. Autoflowers give you raw speed and a small, simple plant; fast photoperiods give you a bigger, trainable harvest that still finishes ahead of the slow strains. The right kind of fast flowering cannabis depends on whether you’re racing the calendar or just trimming a few weeks off a full-size grow.
If pure speed is the goal, autoflowers win. They’re the heart of any fast flowering cannabis lineup because the entire plant — not just its bloom — is built to finish quickly — and as a bonus, most are beginner-friendly and stay compact. Here are the quickest we stock.
Mandarin Cookies Autoflower is the fastest finisher in our catalog at a listed 7–9 weeks, a citrusy hybrid rated High (18–25%) THC and graded Easy to grow. If you want the shortest possible wait without giving up potency or flavor, this is the one to start with.
White Widow Autoflower finishes in 8–9 weeks and is about as forgiving as fast flowering cannabis gets — an Easy-rated hybrid built on one of the most famous strains ever bred. A great first auto if Mandarin Cookies is sold out or you want a proven name.
Speed usually costs a little potency, but Gorilla Glue Autoflower doesn’t read the memo: it finishes in 8–10 weeks and is rated Very High (25–30% and above) THC. It’s graded Moderate rather than Easy, so it’s the pick for a grower who wants quick and heavy-hitting.
For an energetic, daytime-leaning finish, Green Crack Autoflower wraps up in 8–10 weeks. If you’d rather a heavier, relaxing harvest on the same quick clock, Mazar Autoflower is a hardy 8–10 week classic that takes a beginner’s stumbles in stride. Both are proof that fast flowering cannabis doesn’t lock you into one kind of high.
Want a wider shortlist with an eye on ease rather than pure speed? Our guide to the best autoflower strains for beginners goes deeper, and you can browse the whole autoflower seed collection to compare flowering times yourself.
Autoflowers aren’t the only fast flowering cannabis option. If you prefer photoperiod plants — for bigger yields, cloning, or training — you can still get a fast flowering cannabis harvest by choosing strains that bloom on the short end. The rule of thumb: lean indica, avoid long-running hazes, and check the flowering time before you buy.
Bubble OG is one of the quickest photoperiods in the catalog at 8–9 weeks of flower — a relaxing hybrid rated High (18–25%) THC. For a feminized plant that still finishes ahead of the pack, it’s a strong first choice.
Classic indicas are the photoperiod world’s fast finishers. Northern Lights Skunk and Afghani both flower in 8–10 weeks, both are graded Easy, and both are hardy enough for a beginner or a tricky climate. These are the strains that finish before an early frost catches them.
If you want a familiar name that still finishes early, Bubba Kush (a true indica), AK-47, and Blue Dream all land at 8–10 weeks of flower. They’re not as fast as the autoflowers, but for a full-size photoperiod plant they’re at the quick end — and all three are widely loved for good reason.
Outdoors is where finishing speed really earns its keep, and where fast flowering cannabis is worth the most. If your season is short or your autumn turns wet and cold, a slow strain can get caught by frost or rot before it ripens. Fast flowering cannabis sidesteps both problems by being done sooner.
Autoflowers are the ultimate short-season outdoor play: because they don’t wait for the nights to get long, you can start them late, finish them early, and even squeeze in more than one round in a single summer. For photoperiod growers up north, sticking to the quick indicas above and getting plants out early gives them the best shot at ripening. Either way, finishing before the damp sets in is your best defense against bud rot, and our region guides — growing cannabis outdoors in Canada and the Eastern US — cover the timing in detail.
The seed sets the pace with fast flowering cannabis, but a few habits keep a quick strain on schedule. Start autoflowers in their final pot to avoid transplant shock stealing days they can’t spare. Don’t stress an auto with heavy training — its short life leaves no time to recover. Give plants strong light and stable conditions so they never stall.
And know what ripeness actually looks like so you harvest your fast flowering cannabis at the right moment rather than guessing — our guide on how long cannabis takes from seed to harvest lays out the full timeline. Choosing genetics is step one; matching them to your setup is the rest of the job, and our how to choose cannabis seeds guide helps with that.
By our catalog data, Mandarin Cookies Autoflower is the quickest at a listed 7–9 weeks. Among photoperiods, Bubble OG at 8–9 weeks of flower is one of the shortest.
For total time from seed, almost always yes. An autoflower runs its whole life on a fixed clock and skips the long vegetative wait, so the entire grow is often done in around two months. A photoperiod plant spends weeks in veg before it even starts to flower, so even a fast-blooming one takes longer overall.
Not necessarily — fast flowering cannabis trades plant size for time, not strength. Autoflowers yield less per plant than a big trained photoperiod simply because they’re smaller, but potency doesn’t have to suffer — Gorilla Glue Autoflower is rated Very High (25–30% and above) THC despite its quick 8–10 week finish. With fast flowering cannabis you trade plant size for speed, not necessarily strength.
That’s exactly what they’re for. Autoflowers are ideal because they ignore the light cycle and finish on their own schedule, letting you start late and harvest before frost. Among photoperiods, stick to the quick indicas and get them outside early.
With autoflowers, often yes. Because they finish in roughly two months regardless of season, many outdoor growers run two or even three back-to-back rounds across a summer, which photoperiod plants can’t do outdoors.
If finishing fast is the priority, start your search for fast flowering cannabis with autoflowers — they’re the core of the category, and Mandarin Cookies Autoflower at 7–9 weeks is the quickest we carry. If you’d rather grow photoperiods, lean toward short-flowering indicas like Bubble OG, Northern Lights Skunk, and Afghani, and check the flowering time before you buy. Speed doesn’t have to cost you potency or flavor; it mostly costs you plant size, which is a fair trade when the calendar (or your patience) is the real constraint.
Ready to pick one? Browse the full autoflower seeds and feminized seeds ranges, or work through our cannabis growing guides to plan the grow around your season.
Shop Cannabis Seeds | Best Autoflower Strains for Beginners | Autoflower vs Feminized | All Cannabis Growing Guides
Want to keep learning? Browse our full library of guides to growing cannabis — everything from germination to harvest, in one place.
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