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Photo Period Cannabis Seeds

Bigger plants, better yields, and full control over your grow

Feminized cannabis seeds are bred to produce almost exclusively female plants, which are the ones responsible for producing the resin-rich flowers growers actually want. Unlike regular seeds—which typically produce a 50/50 split between male and female plants—feminized seeds eliminate the guesswork and wasted space.

Most feminized seeds are also photoperiod strains, meaning their growth cycle is controlled by light exposure rather than age. This gives indoor growers full control over plant size, structure, and timing.  

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Photo Period Cannabis Seeds & Growing Info

So in comparison to Auto Seeds that flower after 4 to 5 weeks of growing regardless of the light cycle, Photoperiod cannabis seeds rely on light to know when to start flowering. When they are growing they need a lot of light.   ie. more than 18 hours a day. When you reduce the light to 12 hours a day the plant starts to flower. This is an advantage because you control when the plant flowers, how big it gets and how much it produces.

Feminized seeds are often labelled as ‘photo period’ but this is not accurate as you can have feminized photo and feminized auto seeds.   Both solve one of the biggest problems in growing cannabis, which is male plants.  Male plants do not produce flowers and must be avoided if you want Sen similia (female cannabis flower).   

Key Benefits of Photo Period Seeds

  • Full Control Over Growth Cycle – You decide when plants switch from vegetative growth to flowering by adjusting light cycles
  • Bigger Yield Potential – Longer vegetative periods allow plants to grow larger so they can support larger flowers
  • Stronger Root Development – Extended veg time allows roots to fully establish, leading to healthier plants and improved nutrient uptake.
  • Flexible Grow Size (Indoor) – You can keep plants small or grow them into large, high-yielding specimens depending on your space and goals.
  • Wider Genetic Selection – Most premium and legacy strains are available as photoperiod seeds, giving access to the best genetics.

Key Weaknesses of Auto Flower Seeds

  • Longer Grow Time – Requires more patience—typically several weeks longer than autoflower grows.
  • Light Cycle Dependency – Indoor growers must strictly control light schedules; mistakes can delay or ruin flowering.
  • More Complex for Beginners – Requires a better understanding of plant cycles, lighting, and timing.
  • Seasonal Limitations Outdoors – Outdoor grows rely on natural daylight cycles, limiting planting and harvest windows.
  • More Maintenance – Training, pruning, and canopy management require time and effort.

Background - Birds and the Bees

In case you are not a botanist, here is a quick blurb about how plants reproduce.   It’s actual birds and bees stuff!

Ultimately, the main goal of every living thing is to reproduce.   When you see a colorful flower, that is basically the plants mechanism of attracting insects.   The insect collects pollen and transfers the pollen from flower to flower.  Due to the incredible fundamentals of evolution, reproduction requires a male to pollinate a female flower.  

So most plants create 2 types of flowers.  Male and female.   The insect spreads pollen from the male plant to the female plant, and voila!   The flower is fertilized and that plant can now go about it’s job creating seeds for reproduction.

So what?

OK, so if a male marijuana plant is present, the female plant will spend most of it’s energy producing seeds so it can reproduce.   But, if there is no male plant present, the female plant will just grow more and more flowers (pistols) to attract the male pollen.   Luckily, the female flower (Sen Similia) is the one that produces all the THC, so more female flower = more THC rich cannabis flowers!

Cannabis is basically a sexually confused female marijuana plant that is trying to reproduce by making more and more flowers!   

Pistols

about feminized cannabis seeds

cannabis flower black background
cannabis flower up close

When a marijuana plant is fertilized, the female plant will produce seeds.  These seeds will grow into male or female plants at a ratio of approx 50/50.   

But as above, marijuana growers don’t actually want male seeds.  Males in the grow area, will just create cannabis flowers with seed.  This is not ideal as the resulting buds do not contain the same levels of THC or the desired structure that we know and love.   

Amazingly, through incredible human ingenuity, we have worked out a consistent method for producing cannabis seeds that will go on to produce female plants like 99% of the time.   These are called ‘feminized seeds’ and they are the cornerstone of the cannabis growing industry. 

So simply put feminized seeds produce female plants.   

 

Photo Period vs Autos - When to go Photo Period - FAQ

Most growers will chose photo period plants.   If growing indoors, they’ll simply change the light cycle from 18+ hours p/day to 12 hours p/day when they want the plant to start transferring into flowering mode.   This is a tried and test method.   When growing outdoors however, this is where the Auto vs photo debate is worth looking into.  Auto’s will shorten and simplify the whole grow process.  They’ll also allow you to produce multiple crops per season.   Whereas photos’s (outdoor), you just gotta let them do their thing.   Sometimes this means the plants become extremely large and unruly.   Yes, you may end up with crazy yields but it will take generally 4+ months and likely stink out the neighborhood.    So it depends on what you’re after….

 

Autoflower cannabis seeds produce plants that flower automatically based on age rather than light cycles.  Photo period plants will produce flowers based on the light cycle changing (eg. indoors switching from 18hrs p/d to 12 hours p/d & outdoors, sun going lower in the sky).

No.   There are feminized photo period and feminized autos.   Often, the term ‘feminized is synonymous with ‘photo period’ as photo’s are more accepted and popular in the cannabis growing community. 

Typically no, however if the plant is stressed, it can produce both types of flower.  This is called hermaphrodites and it’s something to keep any eye on in any grow as the presence of male flower will pollinate the female, producing unwanted seeds 

Feminized seeds can last for 2-5 years if stored properly.  Just store them in door of your fridge in a small air tight glass jar.   

You should use 18 hours of light and 6 hours of darkness for the vegetative stage and 12 hours of light and 12 hours of darkness for the flowering stage.

CG Australia - Feminized AUTO CANNABIS SEEDS

Our Feminized Photo Period Strains have been curated over many years and we only keep the best ones with top performance based on thousands of reviews.   You can be assured these feminizer photo period strains are top performers and well with your attention assuming you nail the germination policy.