Autoflowering Cannabis: Everything You Need to Know

Autoflowering cannabis plants flower automatically without the need for a change in lighting schedule. Unlike photoperiod cannabis plants which require a change in light cycle to initiate flowering, autoflowering plants usually flower on their own after a certain number of days, regardless of the light cycle. This makes them a popular choice for growers looking for a fast and easy way to cultivate cannabis.

If you don’t have the time or resources to carefully control the lighting conditions in your grow room, the autos are good for you. But what more do they promise?

In this blog post, we’ll explore the history, advantages, and best practices for growing auto-flowering weed plants. 

A Short History of Autoflowering Cannabis

Autoflowering weed plants are a relatively recent development in the history of cannabis cultivation. They were first developed in the late 1990s by crossing cannabis plants with the wild cannabis species Cannabis ruderalis, which is native to Central and Eastern Europe.

Cannabis ruderalis is a small and hardy plant that is well-adapted to harsh growing conditions. It is also unique in that it will flower automatically after a certain number of days, regardless of the light cycle. Breeders cross cannabis ruderalis with regular cannabis strains to create autoflowering marijuana seeds. Auto flowers inherited the ability to flower automatically from the Ruderalis.

Initially, autoflowering strains were not very popular among growers due to their small size and low THC content. However, as breeding techniques improved and new strains were developed, autoflowering marijuana strains became more popular and widely available. Today, autoflowering strains are a popular choice among growers due to their fast flowering time, small size, and ease of cultivation.

What Differentiates Autoflowering Strains from Photoperiod Strains? 

Autoflowering strains flower automatically after a certain number of days, regardless of the light cycle. They’re programmed that way, they flower without you initiating it. Photoperiod strains will only flower if you change the light cycles.

Most growers find autoflowers the right place to start a cannabis growing journey because you won’t have to fiddle with the lights or have an automated system for the light cycles.

This is in contrast to photoperiod cannabis strains, which won’t flower until you change the light cycle. This’s why it’s important to know the strain you’re growing, you can’t imagine waiting for a photoperiod plant to flower when in a lighting schedule meant for autoflower plants.  

The plant will outgrow its space while you’re still waiting for the slightest indication of impending flowering, but no, the plant won’t flower until you change the light cycle. 

Also, auto strains tend to have shorter growth and flowering cycles, typically taking anywhere from 7 to 12 weeks to go from seed to harvest. This is due to the fact that they flower based on age rather than light cycle. Photoperiod strains mostly take between 10–16 weeks. 

Autoflowering Vs. Photoperiod Strains: Ease of Growing

Photoperiod strains are tougher to grow than autoflowers because they need a change in light cycles to induce flowering. They also tend to grow much taller, demanding more maintenance through training—pruning, FIMing, et cetera. 

Yet, these strains offer growers a greater level of control. You can keep a photoperiod strain in the vegetative state indefinitely with at least 18 hours of daily light. This allows indoor cultivators to nurture large plants before switching to a 12-hour-on, 12-hour-off light cycle to trigger the flowering stage. The bigger the plant, the greater the yield. 

Photoperiods also give the option of growing many little plants that mature faster and take a smaller space. You do this by maintaining a 12-hours-on, 12-hours-off light cycle from start to finish with fast-yielding cultivars. Opting for smaller plants especially makes sense when you want to be discreet.  

Autoflowering vs. Photoperiod: Plant Size

 Autoflowering plants tend to be smaller and more compact than photoperiod strains, making them a good choice for growers who have limited space. Their small size and short growth periods are a superpower when you’re going gorilla, but their small size also means there are fewer bud sites, thus small harvest compared to the giant photoperiod strains. 

Advantages of Autoflowering Cannabis

Autoflowering seeds are known to grow without many hassles and mature faster. They are thus beginner-friendly—begin here if you’re new to cannabis growing.  Here are more reasons to try autoflowering weed. 

Fast flowering time: One of the biggest advantages of autoflowering marijuana is their fast flowering. They typically take 7 to 12 weeks to go from seed to harvest, which is much faster than photoperiod seeds, which can take anywhere from 8 to 12 weeks just to flower. This makes autoflowering strains a good choice for growers who want to get multiple harvests in a single growing season.

Small size: Auto strains tend to be smaller and more compact than photoperiods, which makes them a good choice for growers with limited space. They also tend to be more suitable for stealth growing, as they can be easily hidden in small spaces or disguised as other plants.

Wide range of genetics: Autoflowering strains are available in a wide range of genetics, including sativa, indica, and hybrids. Growers can thus choose autoflowering strains that fit their specific growing conditions and preferences.

Multiple harvests: Because of their fast flowering, autoflowering strains can be harvested multiple times in a single growing season, which can increase the overall yield of your grow.

Tips and Best Practices for Growing Autoflowering Cannabis

Growing autoflowering plants can be a rewarding and enjoyable hobby. On top of ditching ditch-quality weed from your dealer, you can tweak the growing conditions to reward yourself with a higher THC level. 

Though they’re easy to grow, you need to pay attention to their needs to get all the frosty goodness. Here are some tips and best practices for growing autoflowering marijuana:

Select the right strain: There are many autoflowering weed strains available, but pick one that fits your specific growing conditions and preferences. Consider factors such as the strain’s genetics (indica and sativa strains, or hybrid), flowering time, and potential yield when selecting a strain.

Also think about what you want from the buds; the effect you want to feel when you use them, then find a strain that satisfies that need. 

Start with good quality seeds: Good quality seeds are essential for successful cannabis cultivation. To choose autoflowering seeds, look for seeds from reputable seed banks that have a high germination rate and are free from pests and diseases. When you get it wrong with the seeds, your results are skewed.

A lot goes into identifying healthy autoflowering cannabis seeds, but start by selecting mature seeds. When cannabis seeds mature they turn dark brown, black, or a blend of both colors. These have a higher germination rate.

Avoid using green seeds. They are most probably not mature enough to germinate. Both larger and smaller seeds can be viable. Indica seeds typically appear larger than sativa seeds, and their patterns differ too. Brown and black seeds are likely indica, while single-colored seeds are generally sativa. I hope these insights will give you a clue on what seeds to pick. 

Use a suitable growing medium: Autoflowering cannabis plants can be grown in a variety of growing media, including soil, coco coir, and hydroponics. Choose a medium that is well-draining and has a neutral pH, and consider adding amendments such as compost or worm castings to improve the nutrient content of the soil.

Since they generally take a shorter time to harvest, you want to get their nutrients needs right so that you don’t waste their growth on recovery. It will be an intense ride keeping the growth conditions in check—just because you don’t adjust the light cycles doesn’t mean other growing chores lessen.

No! You’ll still need to water and feed them accordingly. 

Provide adequate lighting: Autoflowering weed plants will thrive under a consistent light schedule of 18 hours of light and 6 hours of darkness. Use a high-quality LED or HPS grow light to provide the necessary light intensity and spectrum for optimal growth.

Control the temperature and humidity: Autoflowering cannabis plants prefer a temperature range of 70-80 °F (21-27 °C) and a relative humidity of 40-60%. Use a thermometer and hygrometer to monitor and maintain these conditions in your grow room.

Water and feed regularly: Autoflowering cannabis plants have a relatively low nutrient requirement, so it’s important to use a light fertilizer and not over-fertilize. Water your plants regularly, keeping the soil evenly moist but not waterlogged.

Prune and train your plants: Autoflowering plants tend to grow more vertically than horizontally, so it can be helpful to prune and train them to encourage a more even canopy. This will help ensure that all parts of the plant receive an equal amount of light and nutrients.

However, do not go overboard with training because they never have enough time to recover after a high-stress training. 

Common Challenges of Growing Autoflowers

Autoflowering strains are hardy and can take a beating. They will be more forgiving of beginner errors than photoperiod strains. Still, they’re more vulnerable in other areas as well. Here are some common challenges and solutions:

  1. Nutrient burn: Autoflowers have a relatively low nutrient requirement than regular seeds, so it’s pretty easy to overfeed them, leading to nutrient burn among other problems. Consider using a light fertilizer and not over-fertilize.
  2. Heat stress: Autoflowering weed prefer a temperature range of 70-80 °F (21-27 °C) and can suffer from heat stress if the temperature gets too high. To prevent heat stress, use fans or air conditioning to maintain a comfortable temperature in your grow room and avoid placing your grow lights too close to the plants.
  3. Overwatering: Autoflowering cannabis plants are prone to root rot if they are overwatered. To prevent overwatering, water your plants only when the soil is dry to the touch and consider using a soil moisture meter to monitor the moisture content of the soil.

  4. Lower Yields: Most growers avoid autoflower weed because they’re generally low yield. Their smalls size and shorter growth circle means they don’t have enough bud sites to compete photoperiods in yield. You will naturally reap smaller, though you can boost the harvest by using low-stress training methods and choosing high-yielding autoflower cannabis seeds like Northern Lights Automatic, Black Jack Auto or Royal Cheese Auto.

    Always begin with the best autoflower seeds. You don’t get massive yields with low-yielding strains, even if you tweak growth conditions to an absolute best. 
  5. Low potency: Autoflowers are mostly low on THC and CBD levels than their photoperiod counterparts. But potency is a complex matter, even within autos, they vary a great deal in cannabinoid content. This is where you decide which compound you’re interested in, then nurture the plant to yield much of it. 

How Much Do Autoflowering Strains Yield?

On average, an autoflowering cannabis plant can yield anywhere from 0.5 to 3 ounces (14 to 85 grams) per plant. However, this can vary significantly based on the strain, growing conditions, and cultivation practices. Some high-yielding autoflowering strains can produce yields of up to 6 ounces (170 grams) per plant under optimal conditions.

In general, autoflowering strains tend to have lower yields compared to regular strains, due to their smaller size and shorter flowering time. However, because they have a faster flowering, it is possible to get multiple harvests in a single growing season, which can increase the overall yield. 

Their shorter maturity time compensates for the small yields. 

That being said, there are now many high-yielding autoflowering strains available that can produce good yields in the right conditions. Some of these strains have been specifically bred to increase their size and yield, while still maintaining the fast flowering time and ease of cultivation that are characteristic of autoflowering strains.

Ultimately, the yield of an autoflowering cannabis plant will depend on a variety of factors, including the strain, growing conditions, and cultivation practices. By choosing a high-yielding strain and providing optimal growing conditions, it is possible to achieve good yields with autoflowering cannabis plants.

Autos’ shorter maturity time compensates for the small yields. 

Grow Room Conditions for Autoflowering Cannabis

Temperature — Keep a temperature range of 70-80 °F (21-27 °C). They can tolerate slightly cooler or warmer temperatures, but it’s important to keep the temperature within this range to ensure optimal growth.

Humidity — Autoflowering cannabis plants prefer a relative humidity of 40-60%. Too much or too little humidity can affect the health and growth of the plants. Use a hygrometer to monitor the humidity in your grow room and use a humidifier or dehumidifier to maintain the desired humidity level.

Lighting — Autoflowering cannabis plants require a consistent light schedule of 18 hours of light and 6 hours of darkness. Use a high-quality LED or HPS grow light to provide the necessary light intensity and spectrum for optimal growth. Keep your grow lights at a suitable distance from the plants (usually about 18 inches) to prevent light burn.

Air circulation —  Good air circulation is essential for marijuana to thrive. Use fans or air conditioning to maintain a consistent airflow in your grow room and avoid placing your grow lights too close to the plants to prevent heat stress.

Nutrients — Autoflowering weed have a relatively low nutrient requirement, so it’s important to use a light fertilizer and not over-fertilize.

Choose a fertilizer that is specifically formulated for cannabis and follow the instructions on the label for proper dosage and frequency. Due to their low nutrient needs, it’s easy to overfeed them, so check for signs of nutrient burn before it escalates. 

Best Autoflowering Cannabis Strains Based on Yield

There are now many high-yielding autoflowering cannabis strains available on the market when grown in the right conditions. Some examples of high-yielding autoflowering strains include:

  1. Northern Lights Auto: This classic indica strain is arguably the best autoflowering cannabis, thanks to its high yields and potent effects. It can produce yields of up to 5 ounces (140 grams) per plant.  Northern Lights Auto matures in 10 weeks from seed to harvest. Thriving in mild and cold climates, it’s a versatile strain for indoor or outdoor cultivation. Indoors, it reaches about 120 cm, while outdoors, it flourishes at approximately 160 cm.
  2. Gorilla Glue Autoflower: This popular hybrid strain is known for its high THC content and heavy yields. It can produce yields between 5 to 15 ounces per plant and flowers between 7–10 weeks. Experience pure relaxation with ILGM’s Gorilla Glue Auto, the ultimate strain for unwinding after a tiring day. With a single toke, stress vanishes, and in its place, euphoric waves of serenity and tranquility wash over you. Embrace the soothing embrace of this remarkable strain and let your worries drift away.
  3. Amnesia Haze Autoflower: This sativa-dominant strain is known for its uplifting effects and high yields. Its flowering spans 10 to 14 weeks. If you choose to cultivate indoors, you can anticipate around 5 ounces per square meter, whereas outdoor growth boasts a yield of up to 15 ounces per plant. This strain is undeniably generous in its harvest. Standing at a petite 26 inches tall, Amnesia Haze autoflower embodies the typical compactness of autoflowering strains.
  4. Auto White Widow: This strain is known for its high THC content and high yields. It can produce yields ranging from 5 to 15 ounces per plant as it gracefully matures over 10 to 14 weeks. Standing tall at 20 to 24 inches, these plants showcase their elegance and potency. It’s no doubt one of the best autoflower strains you can get your hands on. Embrace the journey as this strain delights you with its bountiful buds and captivating growth.
  5. Auto Critical : This indica-dominant strain is known for its high THC content and heavy yields. It can produce yields of up to 6 ounces (170 grams) per plant and flowers for around 8–9 weeks. Auto Critical stands as an exceptional autoflowering hybrid, boasting top-tier quality while delivering the quintessential impact akin to indica strains. Potent, deeply calming, and with a lasting embrace, its physical influence surpasses its cerebral aspects, rendering it the perfect marijuana strain for unwinding at day’s end and embracing tranquility.

Why Are Autoflowering Strains Considered Discreet?

Autoflowering cannabis strains are considered discreet for a few reasons. First, they tend to be smaller and more compact than regular strains, which makes them easier to hide or disguise as other plants. This makes them a good choice for growers who want to keep their cannabis cultivation discreet.

Autos are also considered discreet because they flower faster than regular strains. This means that they can go from seed to harvest in a shorter period of time, which can make them less noticeable to others.

Finally, autoflowering strains are less reliant on light cycles and other environmental factors, which means they can be grown indoors or outdoors with relatively minimal attention. This can make them a good choice for growers who want to keep their cannabis cultivation low-profile.

The smaller size, faster flowering, and ease of cultivation of autoflowering strains make them a good choice for growers who want to keep their cannabis cultivation discreet.

Are Autoflowers More Resilient Than Photoperiod Strains?

Autoflowering weed strains can be more resilient than photoperiod strains in some ways. They’re not affected by changes in light cycles, mature faster, and are generally hardier—thanks to the power of Ruderalis they owe their ancestry. 

One advantage of autoflowering strains is that they are more resistant to changes in the light cycle. Unlike photoperiod strains that rely on a specific light schedule (usually 18 hours of light and 6 hours of darkness) to trigger flowering, they flower automatically after a certain number of days regardless of the light cycle. This makes them more forgiving of changes in the light schedule.

Autoflowers are generally easier to cultivate than regular strains. They flower faster and require less attention to lighting and other environmental factors, which can make them more forgiving of mistakes or changes in conditions.

Is Autoflower Better Than Feminized?

Autoflower and feminized seeds are both great. It all depends on what you want from your grow. If you’re seeking a bountiful harvest then feminized seeds are the go-to choice. With feminized seeds you’re sure that there won’t be male plants and thus ensures a high-yield and cannabinoid-rich buds from an all-female garden. However, if you want a quick harvest, then autoflowering seeds are a perfect choice.

The whole idea of feminized seeds is to rule out any chance of having a male plant in your grow room. Male plants spoil the fun. They fertilize your female flowers shifting their focus from cannabinoid production to seed nurturing, leading to low yield and poor quality buds. 

Why is Training Autoflowering Strains Risky?

Training autoflowering cannabis strains can be risky because these strains are generally smaller and more compact than regular strains, which means they have less energy and resources to devote to training techniques. Additionally, because they flower faster than regular strains, they have less time to recover from any stress or damage caused by training techniques.

Here are some specific risks to consider when training autoflowering cannabis strains:

  1. Stress: Autoflowering marijuana are more sensitive to stress than regular strains, so it’s important to use training techniques gently and sparingly to avoid stressing the plants. Overdoing it with training techniques can cause the plants to become stunted or even die.
  2. Damage: Training techniques such as bending and pruning can cause damage to the plant if they are not done carefully. It’s essential to use gentle, slow-release ties or clips to secure the branches in place, and to prune off excess growth or branches that are not receiving enough light to prevent further damage to the plant.
  3. Reduced yield: While training techniques can help improve the structure and yield of autoflowering cannabis plants, they can also reduce the yield if they are not done carefully. It’s critical to balance the benefits of training with the potential risks to avoid decreasing the yield of your plants.

In Conclusion

Autoflowering cannabis seeds are a popular choice among growers due to their fast flowering time, small size, and ease of cultivation. These strains are created by crossing regular cannabis strains with the wild cannabis species Cannabis ruderalis, which is known for its ability to flower automatically after a certain number of days. With several advantages and sizeable yield, auto flowering cannabis are a good option for busy and novice growers.