As the cannabis industry continues to evolve from one perceived “phenomenon” to another, one has to wonder to what extent these new developments will improve the growth and sustainability of this multidisciplinary enterprise moving forward. For example, the seemingly systematic adoption of cannabidiol (CBD) as a panacea has made for its rather ubiquitous integration into a wide range of household products, from creams and lotions to condiments and beverages.
Unfortunately, this has led to an anxiety-fueled mania that has triggered exponential growth in the cultivation of Group III cannabis (hemp), which ultimately triggered a precipitous decline in hemp commodities pricing, with many farmers and entrepreneurs holding the bag. One could argue that the unregulated surge in hemp cultivation fueled its own demise and did not make a resounding, beneficial impact on the cannabis industry for more than a couple of years.
With that in mind, is there something else out there on the cannabis cultivation horizon, beyond the mass production of a single cannabinoid, that can have a lasting and sustainable effect on this burgeoning industry? The answer may come from a humble origin.
Cannabis ruderalis genetics originated from Asia and Europe, where they adapted to extreme environments and relatively short growing seasons. Ruderalis plants are generally short and stocky compared to their indica and sativa counterparts, but are most famously known for producing flower material that is grown independent of photoperiod. As a result of this characteristic, ruderalis-based varietals are often referred to as “autoflowers,” as they uniquely flower in conjunction with producing vegetative mass.
Ruderalis genetics are often unfairly characterized by the slang term “ditch weed,” which is a reference to the plant’s robust ability to grow almost anywhere, such as the barren terrain one might find on the side of a railway line, as well as its relatively low phytochemical content. Many associate ruderalis varietals with “fiber-type” hemp, which generally expresses very low levels of primary cannabinoids (THC, CBD, CBC), and little to no terpene content.
Nonetheless, the latest commercially available autoflowering genetics have come a long way in recent years, both in phytochemical production and in the ease of use.
Opportunities with autoflowers
One of the most compelling attributes of autoflowering varietals is how easy they are to grow. Because of their independence from the traditional photoperiod, autoflowers, or “autos,” can be grown by anyone from a renowned Master Grower to a keen newbie with little to no experience.
Imagine going into your local grow store and buying an auto seedling in a five-gallon pot of premium soil that you can then put on your porch or in a window to enjoy cannabis cultivation on the easiest level. It’s akin to the”‘set it and forget it” style of making a delicious pot roast (pun intended!) in your Instant Pot while spending your time away from the kitchen.
As the perception of cannabis as a viable medicine is continuing to expand well beyond the initial subculture, autoflowering varietals could be the gateway for any untrained yet interested party to dabble in personalized cultivation, thus making cannabis more approachable for the masses.
Even enthusiasts with a small backyard greenhouse or a single 4-by-4 grow tent can produce dispensary-quality medicine with the correct autoflowering genetics (Figure 1) because most elite-level autoflowering varietals express all of the same medicinal benefits and phytochemicals (cannabinoids, terpenes, and flavonoids) as their photoperiod counterparts, with the additional ability to grow and flower pretty much anywhere in the world.
Furthermore, using regular, non-feminized auto seed for food and textile crops is a reproducible process that could create unique economic opportunities for developing nations with very little capital investment or infrastructure required.
Additionally, autoflowering analogs of specific photoperiod strains can be produced through selective breeding cycles, just like any other genetic. The ability to breed autoflowering characteristics into different cannabinoid types and strains of cannabis has allowed the industry to enjoy a much more robust repertoire of options compared to the undesirable ruderalis genetics that occupied grow rooms as little as five years ago.
Another positive characteristic of autoflowering varietals is the relative speed of their growth cycles. Autoflowers quickly outpace their photo-dependent counterparts after germination, reaching their adulthood after around two to three weeks versus four to six. From there, autos immediately begin their reproductive stage, producing the first pistils that will multiply into buds.
But the vegetative growth doesn’t stop at this point. Autoflowers continue to show how specialized they are in producing plant material quickly, as they grow in stature rapidly through the first month or more of flowering (Figure 2). After that, outward growth comes to a halt, and the plant focuses on producing terpenes and cannabinoids. Usually, autoflower varieties take from 12 to 14 weeks from germination to reach their height of ripeness.
Today’s skilled breeders have created genetics that produce better quality flowers in an amazing eight to 10 weeks from germination. In contrast, common, photo-dependent cultivars need an additional four to six weeks of long-day, vegetative growth before their eight to 10 weeks of flowering time to achieve the same production.
Challenges with autoflowers
Autoflowering genetics have been characterized as generally having poor taste and aroma profiles; in many cases, people say the plants have smell characteristics of fresh cut grass and hay. Historically speaking, the phytochemical profiles of many autos have been relatively devoid of terpenes and flavonoids. Breeders have been moving forward with these original ruderalis types and dramatically improving their flavor and aroma by mixing them with market-proven genetics and selecting for the auto flower traits.
Additionally, there is very little time during an autoflower growth cycle to address critical issues in the grow. If you are not growing for commercial use, then airy buds and smaller-than-average yield are no big deal. However, for a farm operating on thin margins, bud structure, yield, and phytochemical content can be make-or-break issues. Understanding how to optimize growing conditions and feeding regimens is key for scale production of these genetic types. As we drift further away from the ruderalis tendency and only identify the autoflower trait, we see less and less of these issues. But it is important that we feed these plants for dense flowers, having a readily available source of organic nutrients abundantly available in the soil for uptake as needed.
The major selling point of an autoflower is its ability to flower under myriad lighting cycles. However, this is also a downfall of this type. If you identify a winning phenotype, it is not possible to take a clone that can be perpetuated for selfing. Even under a 24-hour-a-day lighting cycle, it will continue to flower. Through filial breeding, you can work varieties into a close representation of uniformity, but this is a daunting task, especially when creating feminized seed.
It is important for many to use feminized autoflowering genetics, as the males can and will drop flowers and pollen very quickly after germination. One missed male will pollinate and seed your entire crop. Furthermore, to get an auto to reverse, you must start your chosen reversal method very quickly, leaving very little time to observe each plant’s genetic expression.
It is imperative to start multiple plants for reversal so you can select your actual donor further into flower. This takes time, daily observation, and a bit of luck. Ideally you will find a pair, one reversed and one female, that are nearly identical to each other from which to create your first filial generation. From there, you can further work that line using the aforementioned strategies until you reach uniformity.
Most home growers don’t mind autoflowering genetics that aren’t exactly uniform, but at a legal market level, the crop batches must be uniform for accurate tests and consistent product.This is commonly achieved with clones from a mother that are 100% the same. The inability to clone autoflowering genetics makes this nearly impossible. Therefore, all autoflowering genetics must be grown from seed.
Even with a years-long lockdown and a uniformity breeding regimen on these genetics, there is always a chance for a genetic mutation in a seed that can express in many ways. It could be as benign as a differing terpene expression or as detrimental as a hermaphrodite that pollinates and dramatically drops the value of your crop.
Key takeaways
When done properly, one can create an autoflowering genetic that is uniform, consistent, and able to produce multiple crops per year in outdoor or greenhouse settings with very little additional work and no need for supplemental lighting. It is also amazing for locations on the globe with more or less than 12-out-of-12-hour lighting cycles during which typical plants flower before the vegetative cycle can complete, or during which there are highly variable lighting conditions.
Autos are plants that, at the base level, are extremely simple and fun to grow for a home gardener or hobby grower. However, strict steps and robust knowledge are crucial to use them at a commercial level. Is it extremely important as a commercial grower not to buy random market autoflowering genetics because of the likely massive heterogeneity in flowering times, aroma, flavor, plant morphology, and analytical testing results. However, with all of that being said, it’s time to celebrate autoflowering genetics and the opportunities that they present for more folks to explore cannabis and hemp cultivation.
Top 10 Autoflowering Genetics
List of commercially-available autoflowering cultivars. Compiled by Diane Young.
| Cultivar | Genetic Profile | Description | Commercial and/or Reference Source |
| Lemon Blueberry Haze | 75% Sativa25% Indica+Ruderalis | Quick finisher with a sativa kick. 24% THC hybrid leaning sativa-dominant. Excellent plant for indoor, greenhouse, or outdoor. No extra training needed. Mold and pest resistant. Energy, motivation, and relaxed muscles are all hallmarks of this genetic. Flower ready 7-9 weeks from germination. Blueberry x Lemon Haze. | Dynamic Research and Development |
| Blue Sherbet Skunktail | 50% Indica50% Sativa+Ruderalis | Complex cross of Blue Sherbet crossed into a Skunk line. 25% THC hybrid. Developed for a small footprint grow. Will grow in a multitude of conditions and grow styles. Candy, OG funk, and strong “melting rubber” flavor profile. A great genetic for pain management, relaxation, and appetite. A quick finisher at 7-9 weeks from germination. Blue Sherbert Skunktail BX2. | Dynamic Research and Development |
| Gorilla Cookies | 55% Indica45% Sativa+Ruderalis | This is a massive producer of golf-ball-size buds that need support. Grows indoors and out, beginner-friendly. Resilient to cold, molds, and mildew. Flowers in 30-40 days. Creative, euphoric, happy high. | 2fast4buds.comherbiesheadshop.com |
| Strawberry Banana | 70% Indica30% Sativa+Ruderalis | Up to 27% THC! It produces an uplifting, creative, euphoric, well-balanced effect. The heavy, massive yield needs to be staked. Extremely sweet and fruity, like a taste of summer. Popular with everyone. Strong euphoria eases aches and stress. | 2fast4buds.comherbiesheadshop.com |
| OG Kush | Indica-dominant+Ruderalis | From a classic strain, Indica-dominant with up to 24% THC. A West Coast fave. Grow outdoors or in. Citrusy-fuel aroma and flavor with a potent punch. Simultaneous mind/body effect with a creative mental energy boost, leaving you happy and relaxed. | allbud.comcannaconnection.com |
| Northern Lights | Indica+Ruderalis | A couch-locker of almost pure Indica for a relaxed, happy, sleepy evening. Old-school aroma and a fruity taste. Aids insomnia, stress, and appetite loss. A short, bushy, resilient, easy grower. | 2fast4buds.comherbiesheadshop.com |
| Purple Lemonade | 70% Indica30% Sativa+Ruderalis | Up to 27% THC. The ideal sweet tooth smoke — uplifting, giggly, socializing treat. Complete body relaxation in the daytime and evening kickback time. Tastes like it smells, of berry with a little lime kick. Easy to grow in or outdoors. | 2fast4buds.comherbiesheadshop.com |
| Lamb’s Breath | Sativa-dominant+Ruderalis | 19-23% THC, with huge, sticky buds in 8-9 weeks. Full body and cerebral high. Skunky, cheesy, pungent smell and taste, with sweet, creamy smoke. | allbud.comherbiesheadship.com |
| Granddaddy Purple | 100% Indica+Ruderalis | High THC! Hashy, skunky taste with a touch of spice. Small, ideal for growing indoors, beginner-friendly. Doesn’t hit you hard after a first big toke. | allbud.comleafly.com |
| Bruce Banner | 60% Sativa40% Indica+Ruderalis | Named for the Hulk’s alter-ego, Bruce Banner is delicate and aromatic, but the 27% THC makes it a bonafide “one hit wonder.” Extremely resistant to pests and mildew. It will put you on the couch, so take it easy with the Bruce. | allbud.comleafly.com |
| Extreme Impact | 90% Indica10% Sativa+Ruderalis | Creative with clarity, it’s a lemon-lime slammer. Grows indoors and out. Unique with a citrusy deep hash flavor and dense smoke. Delay toke-time if there’s still something you need to do. | herbiesheadship.comleafly.com |
| Forbidden Runtz | Indica-dominant | A cross between the classic Runtz and Forbidden ZKittlez. Delicious sweet berry flavor with a touch of pine and diesel. It makes it difficult to think of anything serious. Helps with depression, migraines, stress, anxiety, and other head maladies. Can be body tingling and even a bit arousing! | allbud.comleafly.com |
Zacariah L. Hildenbrand, Ph.D. is the principal founder of Inform Environmental, partner of Medusa Analytical and is a research professor at the University of Texas at El Paso, where his work focuses on educating the general public about the scientific merits of cannabis, as well as developing new innovations with cannabis-based therapies.
Adam Jacques hails from Eugene, Oregon, where he is the lead geneticist at ZED Therapeutics. He is also a technical advisor for Curtis Mathes Lighting. He holds a spot on the Editorial Review Board for Cannabis Science and Technology Magazine. Please send correspondence to [email protected].
