Why Beginners Should Grow Auto-Flowering Strains


by Nebula Haze

What’s So Special About Auto-Flowering Strains?

Have you ever heard of “auto-flowering” strains of cannabis? How are these strains different from traditional (photoperiod) strains, and what makes them easier to grow for beginners?

This gorgeous Hubbabubbasmelloscope auto-flowering plant by Awolace produced 4.65 ounces by itself!

Example of a gorgeous topped auto-flowering cannabis plant

Why Auto-Flowering Plants Are Great for Beginners

  • Automatically start making buds just a few weeks after they sprout – This is why they’re called “auto-flowering” strains. Traditional strains grown indoors need to be manually forced to start making buds by altering light periods (why they’re called “photoperiod” strains).
  • Plants stay a manageable size – Most auto-flowering strains stay under hip height and will not grow into huge monsters that unexpectedly take over a closet or become taller than your fence. Although some auto-flowering strains can get pretty big, any extra-large strains are typically labeled as such by the breeder.
  • Ready to harvest in 3 months or less – While traditional grows take 3-5 months from seed to harvest on average, auto-flowering plants are typically ready to harvest in 3 months or less from when they first sprout. A lot of growers prefer a quicker harvest that can still produce a lot of bud.
  • Can be grown outdoors in most climates – Traditional outdoor cannabis plants must be planted in the Spring, and need at least 4-5 months of warm-but-not-too-wet weather before Fall. This set of requirements makes it difficult to grow outdoors in a lot of climates. But as long as your climate gets warm, sunny weather for at least three months at a time, you should be able to grow an auto-flowering plant outside. This is great for growers who would like to grow during a short but sunny summer, during warm winter months, or to get an early outdoor harvest.
  • Not sensitive to light leaks or light periods – If light accidentally leaks into the grow space during a traditional plant’s dark period (for example if you open the closet door to look at your plants, or even from a blinking indicator light on a piece of equipment you didn’t notice), it can cause big problems. The amount of time the grow lights are on each day also has a huge effect on how photoperiod plants grow. Outdoors, photoperiods plants are sensitive to the time of year, and their internal cycles can be disrupted by security spotlights, street lights or even the light from a nearby window. Light stress can interrupt bud development or even cause traditional plants to make “male” flowers, which growers don’t want because you can’t really smoke or use them. Auto-flowering plants are basically unaffected by light periods or light leaks. It’s just one less thing to worry about for a new grower.
  • Feminized auto-flowering seeds always make buds – Speaking of male vs female flowers, when it comes to auto-flowering strains you typically don’t need to worry about sex. In fact, you would specifically need to seek out seeds that will produce male flowers because just about all auto-flowering seeds available online are feminized. If you buy feminized auto-flowering seeds, you are basically guaranteed to get a “female” plant, which means that every plant will produce buds and you don’t have to worry about male plants, seeds or pollination.

Did you know? Half of all traditional non-feminized seeds (the kind of seeds you typically find in your bud) grow into male plants that must be removed from the grow room as soon as you spot them. Growing with feminized seeds prevents that potential headache!

Auto-Flowering Frisian Dew by Dutch Passion may produce incredibly vibrant purple buds under the right conditions, and tends to grow well outdoors

Purple auto-flowering Frisian Dew marijuana plant

Auto-Flowering Strains Have Better Genetics Than Ever

All modern auto-flowering plants are the decedents of a type of wild hemp that grows in Siberia known as Cannabis ruderalis, which is a cousin of the THC-producing cannabis plant we know and love. Wild ruderalis plants grow very small buds that don’t contain much THC, but due to the extremely short summers they have the odd quirk of flowering immediately after sprouting regardless of day length.

Some forward-thinking marijuana breeder saw the potential of this and started cross-breeding Ruderalis plants with cannabis strains that contain THC. The results from the initial hybrids were disappointing, but breeders didn’t give up and kept selecting for plants with higher yields and more potent buds while carefully maintaining the auto-flowering capability from generation to generation. Cannabis lore says the first experimental crosses between “Marijuana” and Ruderalis strains were done in the 1960s, with some strains starting to be sold in seed banks by the 1980s.

Ruderalis – This Tiny Wild Hemp Plant is the Ancestor of All Auto-Flowering Strains

A ruderalis cannabis plant in the wild - pic taken in Russia

The first time I heard about auto-flowering seeds was around 2010, when we first started making GrowWeedEasy.com. At the time, auto-flowering strains were often referred to as “Lowryder” plants, or some variation such as “Short Ryder” or “Diesel Ryder”. The “Ryder” strain options were extremely limited at first, but they were starting to catch on.

An original “Lowryder” plant

Lowryder Original Auto-flowering cannabis plant by hypermx

Home growers started demanding more and better options, and some breeders began specializing specifically in making auto-flowering strains (which mostly lost the “Ryder” name). The genetics have been improving exponentially ever since.

Now there are hundreds of auto-flowering strains to choose from, and many traditional strains offer an auto-flowering version. You have competitive breeders that consistently sell auto-flowering seeds that are extremely fast-growing, give you great yields, and produce buds that feel as potent as their photoperiod counterparts.

Auto-Flowering Plants Today Come in a Variety of Strains

Example of auto-flowering (Ruderalis) cannabis plants just before harvest!These auto-flowering plants produced about 2 ounces each (here’s the grow journal)

Auto-flowering plants in 2014

Outdoor auto-flowering plants don’t care about light schedules or the time of year. Your climate is likely suitable to grow an auto-flowering plant if you have at least 3 months of sun and warm weather (above 60°F / 16°C during the day, and no freezing nights). These auto-flowering plants were grown in a homemade greenhouse in a cold climate. They were planted in Spring and ready to harvest before freezing temperatures came, despite a very short summer.

Example of growing auto-flowering marijuana plants in a homemade greenhouse

Complete Auto-Flowering Cannabis Strains Guide

How to Train an Auto-Flowering Plant for Bigger Yields

Can You “Top” an Auto-Flowering Strain?

Nebula’s Recommended Auto-Flowering Cannabis Breeders:

  • Dinafem <– My personal favorite for auto-flowering seeds. I have been impressed every time I’ve grown with Dinafem genetics, including both auto-flowering and photoperiod strains. In fact, I’m currently growing eight auto-flowering plants in my grow tent right now, and although there’s several weeks left to go, the Dinafem plants in the grow tent currently have the biggest buds of all.

  • Sweet Seeds – A seed bank from Spain which has been breeding and improving auto-flowering strains for years. They offer a variety of strains with unique colors and smells like their colorful and sweet-smelling Dark Devil Auto.

  • Nirvana – This breeder consistently provides seeds that are easy to grow, high-yielding and potent. Their auto-flowering strains are no exception.

There are many other great breeders that offer auto-flowering seeds, but we’ve personally had good results with these breeders and feel confident recommending them. Let us know if there’s an auto-flowering cannabis breeder you think should be added to this list!

Blue Cheese Auto by Dinafem

The main cola of an auto-flowering Blue Cheese plant by Dinafem

Dark Devil Auto by Sweet Seeds

Example of the purple bud growing on an auto-flowering Dark Devil cannabis strain

Auto Lemon OG Haze by Nirvana

Auto-flowering Lemon OG Haze cannabis coloa

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