Autoflower Cannabis Seeds

Our most popular autoflowering strains compared

Sorted by time from germination to harvest. All figures come from our breeding programme and the strain data sheets; indoor yield under a 720 W LED on 1.5 m². Under LED, autos usually finish about a week sooner.

All the other autos — including Auto Anubis, Auto Wembley, Auto Kryptonite, Auto Lennon, Auto Galaxy, Auto Olympia, Auto Blue Pyramid and Auto Fresh Candy — are in the product list. Want to try several strains? The Power Mix Auto brings four autoflower genetics together in one pack.

Which autoflower strain suits you?

What are autoflowering seeds?

Autoflowering seeds grow into plants that start to flower on their own after a fixed period of growth — usually 3–4 weeks after germination, however long the days and nights are. The trait comes from Cannabis ruderalis, a hardy wild form from northern regions with short summers. Modern autoflower genetics combine self-flowering with the potency and aroma of classic strains: our autos now reach 18–26% THC.

All Pyramid Seeds autoflower seeds are feminized (feminised) — practically every plant is a flowering female.

Why grow autoflower seeds?

• No light schedule: indoors usually 18/6 or 20/4 from seedling to harvest — fewer things to get wrong
• Fast: 43–80 days from seed to harvest, depending on the strain
• Compact & discreet: mostly 50–160 cm tall — good for a balcony, a tent or a small room
• Several harvests: two runs per outdoor season, and indoors you can sow again all year round
• Hardy: the ruderalis heritage makes autos tolerant of changeable weather

What is the highest-yielding autoflower strain?

In our catalogue it is Auto Tutankhamon and Auto Super Hash, with up to 850–900 g per 1.5 m² under LED, followed by Auto Gorila and Auto Do-Si-Dos with up to 800 g. Outdoors, Auto Gorila gives up to 400–500 g per plant. For more heavy croppers across all seed types, see our high-yield seeds.

Autoflowering vs feminized (photoperiod) seeds

Want the biggest yield per plant? Take a look at our feminized cannabis seeds — or the fast-flowering feminized versions with a shorter bloom as a middle ground.

How to grow autoflower seeds: six rules

Autos forgive a lot, but they have no time to recover from mistakes — the whole cycle is only 6–11 weeks. These six rules make the difference:

• Light: 18/6 or 20/4 from day one to harvest. No switch to 12/12 — the plant flowers by itself.
• Final pot from the start: sow straight into the final container (11–15 l). Transplanting costs autos growing days they cannot make up.
• Airy substrate: a light soil mix with perlite or coco keeps the roots oxygenated and prevents overwatering.
• Feed lightly: autos need less fertiliser than photoperiod plants — start at a reduced dose and increase only if the plant asks for it.
• Train gently: low-stress training (bending and tying down) works well; avoid heavy topping or pruning once the plant is in flower.
• Climate: 20–26 °C, around 60% humidity in growth and 40–50% in flower — this also helps prevent mould in dense buds.

From seed to sprout: how to germinate cannabis seeds, step by step.

Autoflower seeds for outdoor growing

Outdoors, autos are the safest choice wherever summers are short or wet: they are ripe before the autumn rain and cold nights, because they do not wait for the days to shorten. How to plan the season (northern hemisphere):

• Short summers — the UK, northern and central Europe, Canada, the northern USA: first sowing once there is no more risk of frost, from mid-May — harvest from mid to late July; a second sowing by early July still ripens in September, before the autumn rain
• Long summers — the Mediterranean, the southern USA: sow from April to early August — two runs per season with time to spare, and a fast strain can fit in a third
• Fast strains such as Auto Alpujarreña or Auto Gorila make the second run especially safe
• Pot instead of transplanting: sow autos straight into their final container (at least 11–15 l) — repotting costs them valuable growing days

Looking for purple buds in the garden? See our blog: the best purple strains for outdoor growing in 2026. Autoflowers together with the feminized and fast-flowering strains that finish outdoors by the end of September are collected in our outdoor cannabis seeds category.

From the breeder, not a reseller

Pyramid Seeds is a seed producer based in Barcelona, founded in 2002. We don’t buy in other companies’ seeds to repackage them — every autoflower strain in this catalogue comes from our own breeding programme. With autos this matters twice over: only stable lines flower reliably on their own and stay uniform from plant to plant.

• Our own genetics since 2002 — selection and stabilisation in our own programme
• Autoflower versions of our classics — Tutankhamon, Black Cherry Punch, Gelato and White Widow as autos
• Fresh seeds from the current harvest — straight from the producer, no middlemen
• Germination guarantee and bonus seeds in every order
• Discreet shipping to the UK, across Europe, to the USA, Canada and worldwide — neutral packaging, dispatched within 24 hours of payment. Rates and free-shipping thresholds for your country: delivery information

More about us: Pyramid Seeds — cannabis seed bank from Barcelona since 2002.

Updated: October 2026 · Strain data from the Pyramid Seeds breeding programme

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