How Long Does It Take to Grow Autoflowers?
There aren't enough hours in the day. You meant to clean the kitchen, reply to that message, check the weather, do some yoga, and grow spiritually. Instead, you watered a houseplant twice by accident and forgot your coffee in the microwave. Now you're Googling how fast cannabis grows after seeing a post on the anti-social networks calling autoflowers ‘rocket fuel with leaves.’
Time's weird like that. Elastic. Non-linear. One minute, you're scrolling; the next, it's autumn.
But autoflowers? They get it. They don't wait for your schedule to free up. They don't need you to flip the light cycle or chart the lunar calendar. They grow like time doesn't exist. Straight from seed to smoke in a flash. Sort of.
How long do autoflowers take to grow?
The Quick Maths (But the kind we like)
Most autoflowers go from seed to harvest in 8–10 weeks. Some sprint to the finish in 7. Others take their time and stretch it out to 12. It depends on genetics, conditions, and whether or not you've accidentally stunted them with love (aka overwatering, touching them too much, or just checking on them again and again.)
You're not aiming for botanical perfection. You're aiming for a plant that gets the job done before the seasons change or before you grow too impatient for harvest.
Autoflower Life Cycle
Autoflowers don't follow your calendar. They do their thing and flower after 21 days. But if you want a rough idea of how their life unfolds, here's the loose timeline.
Week 1–2: The Seedling Era
Tiny, fragile, and mostly leaves. Not much happens, but you'll still stare at it for hours. The roots are finding their footing, the stem is figuring out gravity, and you're figuring out how not to kill it with kindness.
Don't overwater. Don't start adding nutrients. Just chill. You've got a sprout, not a speedboat.
Week 3–5: The Veg Vibes (Short but Sweet)
This is the awkward teen phase. Fast growth, lots of foliage, but still no sign of flowers. You might think, "Should I top it? Train it? Talk to it?"
Short answer: Maybe. But don't overthink it; autos are on a countdown and are not waiting for permission. Get your lighting, temps, and nutrients on point now, as this is the setup for the finale.
Week 5–10: Flower Power
Boom. Pistils pop, the smell kicks in, and suddenly, it's wearing perfume and demanding attention. This is when the buds stack up, and the THC starts doing its thing. Depending on the strain, the plant might be done in 8 weeks flat or take a couple more to finish her dramatic third act.
And yes, trichomes will mess with your sense of time. One day, it looks clear; the next, it's cloudy, but get a microscope and look properly.
Sunlight > Time?
Here's the thing: autoflowers don't care when the lights are on. But they do care how much light they get. They're like that friend who says, "I don't need a birthday party," but will sulk if you forget.
Unlike photoperiod strains that rely on 12/12 light schedules to trigger flowering, autos just... go. Independent queens. But the more light they soak up, the bigger and better they grow.
Think of it like this:
- 18–20 hours of light a day? You're giving them a protein shake and a hype playlist.
- 12 hours or less? You're basically whispering "good luck" and hoping for the best.
Outdoors, that means timing is everything. You'll want to sow seeds when the sun's sticking around late spring to midsummer, which is your sweet spot. Indoors, you've got more control, but don't skimp on the lumens. Light equals energy, and energy equals buds. It's science. Sort of.
The takeaway? Autoflowers aren't tied to the clock but are powered by the sun. So, if you're wondering why your plant looks more like "basil bush" than "banger nug," check the lighting before you blame the strain.
From Pot to Pot Again
One of the best things about autoflowers? You don't have to wait until next season to go again. These little speed demons are the fast food of home growing. Only these plants are way better for your health and slightly more suspicious to your neighbours.
If you plan it right, you can get two or even three full harvests in one outdoor season. That's right: while other growers are still begging their photoperiods to flip, you could be trimming your second round and wondering if there's room for one more.
It's called "succession planting", but around here, we just call it "being a bit cheeky with the calendar." As soon as one finishes, another can start.
You'll need:
Decent weather (or a good indoor setup)
A fast-flowering strain (think 8–9 weeks)
And the patience to not smoke your entire stash before the next batch finishes
The result? A steady flower supply without the wait, like having your own rolling weed subscription minus the monthly fees. Want to grow all summer and still have time to lose track of it? Autoflowers are your friend.
But Seriously, It Depends
We'd love to tell you that every autoflower takes exactly 70 days, smells like mango gelato, and yields jars of perfectly cured flowers without ever stressing you out. But this isn't a fairytale. It's growing cannabis at home. And autoflowers, while fast, are still plants, not robots.
So yeah, how long it takes? It depends. On what, you ask?
Genetics: Some autos are bred for speed. Others want to show off. A "fast" label doesn't always mean fast if it's been crossed with something... artistic.
Environment: Cold nights? Heatwaves? Damp basements? Your plant has opinions, and it will let you know.
Pot size: Bigger pot, bigger plant, and potentially longer grow time. Small pots = fast and furious. Big pots = slow and heavy.
Feeding habits: Too much nitrogen in flower? Welcome to Delay City. Not enough nutrients? She'll rush to harvest like she's quitting the job early.
You (yes, you): If you keep poking, overwatering, overthinking, and generally treating your grow like a Tamagotchi, things might slow down. Sometimes, the best thing you can do is step back and let nature cook.
So when someone says, "autoflower cannabis seeds take 10 weeks," just remember, that's a rough estimate. Not a concrete timetable. Patience helps, and so does a bit of trial and error.
Autoflowering Cannabis Seeds Online at The Amsterdam Seed Center
Autoflowers grow on their own terms. They're fast, flexible, and refreshingly low-maintenance. They don't wait for your lunar rituals or your light schedule spreadsheets. They just go. And if you give them a decent shot. With enough sun, a little care, and not too much interference, they'll reward you with a harvest that sneaks up on you faster than your to-do list.
So, how long does it take to grow autoflowers? Find out by using our Seed Finder and find the fastest autos on all the land.