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2020: The Decade Of The Autoflower

By Colin Gordon and Ben Owens

Imagine harvesting multiple ounces of your favorite cultivars 10 weeks after planting the seeds. Seems too good to be true, right? Wrong. It’s absolutely possible thanks to advances in auto flower breeding.

For many, the term “auto flower” may be foreign; unlike photo-period plans, auto flowering varietals will transition to flower when they’re ready, regardless of the time of year, light cycle, or other environmental changes.

Historically, growers have looked down on autos as the “easy” option; they don’t require advanced grow knowledge or changes in equipment. Auto flowers, especially in outdoor grows, are among the closest thing to “set and forget” that you’ll find in cannabis genetics. For growers that sought out specific characteristics like aroma, flavor, and yield, these weren’t the genetics that ticked all of the boxes.

Now, breeders like ETHOS are turning that belief on its head, seeking to make it indiscernible whether a plant is an auto flower or not, allowing indoor and outdoor growers to increase their output and shorten their crop cycles, all while decreasing overhead costs.

What are Auto Flowers?
Auto flower plants are plants who are genetically programmed to transition from vegetative to bloom stages automatically, without prompting from their lighting. Unlike photo period plants whose flowering stage is triggered by changes in lighting and environment, autos do not require intervention (indoor) or a specific time of year (outdoor) to prompt the bloom phase. Rather, rhizosphere, root development, and uMole are going to affect the size and flowering time.


Growth Stage Transition: Determined by light

Growth Stages: 2

Growth Time (Seed/Clone to harvest): 12-18 Weeks


Growth Stage Transition: Determined by plant

Growth Stages: 1

Growth Time (Seed/Clone to harvest): 10-12 Weeks

The Difference Auto Flowers Make in Your Garden
Aside from the genetic difference in plant maturation, auto flowers done right can offer a variety of benefits for your grow, whether you’re in a small tent or a multi-thousand square foot commercial facility.

Auto Flower Benefits
Auto flowers shorten the grow cycle but they also reduce costs and knowledge needed to efficiently cultivate and harvest your plants. The automatic flowering nature of these plants means that you won’t need separate sets of grow equipment or grow rooms for your crops. Your crew won’t need to know when or how to change lighting schedules and setups, and the drastic difference in grow duration will mean less hours worked in the garden for similar or better yields. Plus, if you’re growing outdoors, you won’t have to wait the whole season for mother nature to flower your plants; many outdoor grows are able to run three or more cycles of auto flowers in the same season, an impossible feat with photo period plants.

For the more discerning grower, the one drawback to an auto flower is the inability to control the different stages of growth, particularly the lack of control over the vegetative stage as well as the lack of ability to clone it. An auto flower plant will decide it is time to transition to bloom regardless of whether you wanted to keep it in veg for another few weeks (or indefinitely). Previously, many would have argued that there was a limited amount of auto flower genetics even worth growing, but this argument is no longer relevant with the launch of ETHOS Auto Flower line.

Why the market is turning to Auto Flowers?
For the above reasons, many growers are beginning to reconsider their beliefs on auto flower plants, especially after seeing the plants and their harvests firsthand. ETHOS is working to create new auto flower genetics with the most sought after traits from our photo period plants and the ease and efficiency of an auto flower through a two part breeding process. By back-crossing the auto flower filials with their auto flower parent, we are able to stabilize the recessive auto flower trait. From there, directional breeding towards photo period expressions allows for the retention of attractive qualities of the photo period parent plants.

Growing Auto Flowers the ETHOS Way
Caption: This #PlutoAuto is a little over 5 weeks from germination. (include picture)

These seeds were germinated in paper towels at temperatures between 72-80ºF for 3-4 days and put directly in to the 7 gallon cloth pot (its only pot during its life). The seeds are popped with small tails but not out of their shell yet. I plant them about an 1/8" below the top of the substrate (almost peaking through). Maintain a moist substrate on the top of the pot for the first 5-7 days (I mist the tops twice a day.) This allows the seed to grow out properly and have enough moisture as well as air. Warmer temperatures will create a faster germination process but beware that it will also increase the potential for pathogens and problems like mold and damping (the death of a seedling caused by a pithium spore).

Temperature & Humidity
My "daytime" temps are 80-86ºF (ambient room temp). Higher humidity is preferred as well, but anything over 40% should be ok. I shoot for 60-65% for the first 2 weeks.

They LOVE lots of light! I start ramping up light by the beginning of Week 2 and continue through Week 4, where you want to be around 600 uMole at canopy. At this time, I also increase the amount of daylight hours. Depending on uMole strength, 12-16 hours in the first week is plenty. By week 4, I'm on a 20 hours on and 4 hours off schedule at 600-800 uMole. At week 6, 1000-1200 uMole.

I maintain that schedule until the last week of harvest (when they start losing bottom leaves.) I like to go back to lower uMole in the last week. At 800-1000 uMole, 12 hours of light is plenty. If you're running in the 600-800 range, a few more hours of light may benefit.

If you’re considering growing for the first time, or weighing the benefits of adding auto flowers to your garden, consider ETHOS’ newest auto flower offerings like Pluto or Zweet, and the above recipe for success with ETHOS auto flowers. Stay tuned for more auto flower genetics to come as our breeding projects continue.

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