Autoflowering cannabis seeds.

Filters we used, and why

• Autoflower: it flowers by age, not by daylight, so you never change the light schedule. Most stay compact. Autoflower or photoperiod.

What makes a seed autoflowering

Most cannabis plants flower when the nights get longer: that's a photoperiod plant. An autoflowering plant carries genetics from ruderalis, a hardy cannabis from the north, and starts flowering by age instead. A few weeks after sprouting it flowers, whatever the light does.

That one difference changes how you grow:

• Indoors you keep the light on one schedule from seed to harvest, often 18 or 20 hours a day.
• Outdoors you can plant in late spring and harvest in summer, long before the autumn rain.
• The plant stays compact, which suits a tent, a balcony or a spot that needs to stay out of sight.

Autoflower compared with photoperiod

	Autoflower	Photoperiod
Starts flowering	By age, after 3 to 5 weeks	When nights get longer (or at 12 hours of light)
Seed to harvest	About 8 to 12 weeks	About 3 to 6 months
Plant size	Mostly small to average	Average to tall, you control it indoors
Harvest per plant	Smaller	Larger
Room for mistakes	Less time to recover	More time to recover
Outdoor runs per summer	Often two or more	One

Who autoflowers suit

• A first grow: no light schedule to change, and a harvest within a few months. Start with easy seeds for a small tent.
• A short summer: in the UK, the Netherlands, Germany or Canada an autoflower is done before the weather turns. Look at fast autoflowers.
• Little space: a compact plant fits where a photoperiod would outgrow the room.
• Several harvests a year: start a new plant every few weeks for a steady supply.

What to know before you choose

An autoflower runs on a fixed clock. If it gets stressed early, by overwatering, a big transplant or too much feeding, it has little time to recover before flowering starts. Many growers plant autoflowers straight into their final pot for that reason.

Autoflowers also give a smaller harvest per plant than a photoperiod grown for months. Modern autoflowers have closed much of that gap: compare high-yield autoflowers and high-THC autoflowers.

Reading the specs on an autoflower

Breeders count an autoflower's flowering time from seed to harvest, not from the start of flowering, so we do too. On buxbeans, a short autoflower is under 70 days from seed to harvest, and a long one is 84 days or more. Compare that with a photoperiod's flowering time and the autoflower can look slower than it is. How to read it on a seed sheet.

Make it yours

• Feminized autoflowers only: every plant flowers.
• Fast autoflowers: a short seed-to-harvest time.
• High-yield autoflowers or high-THC autoflowers.

Good to know

For autoflowers, breeders count flowering time from seed to harvest, so we do too. How to read it on a seed sheet.

The list is sorted by price per seed, cheapest first, from shops that ship to you and have it in stock. Nobody can pay us for a better spot. How the list is sorted.