The Difference Between Photoperiod And Autoflowering Strains

The weed available on the legal and illegal market generally comes from photoperiod strains. Autoflowering strains are mainly popular with the smaller home grower.

Photoperiod strains switch from the growth phase to the flowering stage when they get fewer hours of light per day. In nature, this means that they will start to flower in the late summer.

Autoflowering strains are not dependent on the length of daylight. They start to flower automatically when they’re a few weeks old (usually 3-4 weeks). This length of daylight vs. age is the main difference between photoperiod and autoflowering strains in a nutshell.

Whether you choose to cultivate a photoperiod or an autoflowering strain will mainly come down to what it is you want as a grower. If the ability to carefully control light cycles to achieve a specific yield is what you seek, then an autoflowering variant may not be the best choice for you.

On the flip side, if you are a novice or first-time grower, autoflowering strains can remove some of the complications that accompany growing photoperiod cannabis.

Although in some respects autoflowering strains are considered “easier” to grow, both photoperiod and autoflowering plants will still require the same care and attention when it comes to nutrients, water, sufficient air flow, and management of pH levels.

Both will also need careful observation should they become the target of an infestation or disease. As long as you can cater to those requirements, both will grow successfully. There will, however, be different outcomes not only for the grower, but the end user as well.



Photoperiod strains are easy to manipulate, which is both a positive and negative trait. If we assume the manipulation is intended, photoperiod strains can grow taller and produce bigger yields than their autoflowering counterparts.

It is possible to keep a photoperiod plant in a vegetative state until you are sure it has the strength and structure to support efficient bud production.

From seed to harvest, growth will take longer than with an autoflowering strain, which makes timing essential for outdoor growers. If you live in a climate that is less than perfect for growing cannabis, the time at which you choose to grow will be vital to ensure it doesn’t get killed off by an early frost or similar environmental factor.

  • Popular and Award Winning Genetics

    Zenpype cannabis seeds bank

  • Grown from certified seeds.

    Zenpype CBD products

  • 12 000 Members Strong

    Zenpype Cannabis Community


Despite the simplicity of autoflowering strains, it is photoperiod strains that can take more abuse, whether that be intentional or the result of mistakes made as a beginner. Their growing states can be controlled by the amount of light they receive; if during the vegetative stage you run into any deficiencies or problems, flowering can be delayed.

If you allow a weakened cannabis plant to flower, there is a good chance yields will be smaller and the potency of the buds will be affected too.

Finally, photoperiod strains can be cloned, producing a nearly endless supply of marijuana plants. If you have found a strain with strong resilience and plentiful bud production, the option to replicate those attributes can all but guarantee success time and time again.


Aside from the growing traits, what does a photoperiod strain offer the end user?

As it is more responsive to light cycles and light intensity in optimal conditions, a higher standard of bud can be produced. Most of the time, both bud production and potency in a well-grown photoperiod strain will be more impressive than with autoflowering cultivars.

Furthermore, the flavor of these plants is usually more well-developed. THC content can reach high levels, as can the density of terpenes present. These days, however, more and more breeders come up with seriously potent and high yielding autoflowering strains so keep that in mind.



Autoflowering strains do just that, flower regardless of the light cycle they are subjected to. Be sure to pick a strain that has a vegetative period that fits within your own time frame, as this process will take place regardless of when you’re ready.

Autos offer less control, but for novice growers, it takes away the complication of extensive light coverage or modification of daylight cycles.

Autos typically have a much quicker total crop time from seed to harvest. That’s not to say some photoperiod strains cannot be harvested within a similar time frame, but autoflowering strains provide ready access to yields in as little as 2–3 months.

Because they are not as influenced by light cycles, autoflowering strains grow a lot shorter than their photoperiod counterparts. Their smaller size can also lead to reduced yields, however—and this is an important however—as the introduction of ruderalis genetics has become more widely experimented with, the efficacy of autoflowering strains has dramatically improved. It is not uncommon to get an autoflowering strain that matches a photoperiod variant for yields and THC content. Moreover, the short stature of autos can be a good thing for those discreet indoor growers looking to harvest covert plants of cannabinoid-rich buds.

Although they are an ideal choice for growers with limited knowledge or a less than perfect growing area, autoflowering strains are actually the ones more susceptible to mistakes. It isn’t possible to delay the vegetative stage to remedy any stress-related issues or nutrient deficiency. Therefore, when it flowers, your buds will suffer if the plant is not in good health.


Nowadays, the experience will be much the same as with photoperiod strains. Autoflowering strains of old were infamous for producing inferior yields and less-potent buds.

Yet as we already mentioned, modern equivalents have come a long way, and the THC content should be comparable. Flavor may be the only factor that is negatively impacted, as the shorter flowering time can limit the full production of terpenes. Moreover, ruderalis genetics themselves aren’t known for being particularly tasty.


The decision to grow either an autoflowering strain or a photoperiod strain will by and large come down to the type of growing environment you can provide. If your setup is able to accommodate adjustable light cycles, plenty of room to stretch, and careful monitoring, then a photoperiod plant will almost always produce bigger yields and better quality buds.

If you are more restricted in where and when you can grow, autoflowering strains make a great alternative. Don’t forget though, other than automatically flowering, they will still need the same TLC as any other type of cannabis seed. As long as you have done your research, both types will reward you with dank buds when all is said and done.

  • 90
0 0 votes
Article Rating
Notify of
Inline Feedbacks
View all comments


Zenpype Cannabis News Feed
Would love to hear your thoughts...x