Pollination (action when cannabis male pollen lands on female pistils) is usually a tricky thing to do and new growers usually just let the male and female plants grow in the same room and let nature do its thing but that is not the best step to take.

What is pollination?

Pollination is the process when male pollen grain gets on to a female calyx (the pistils of the female flower) and slides in the base of the calyx starting the fertilization of the female flower.

In nature, pollination happens when a male plant matures and releases its pollen into the wind and this pollen lands on close by females. When a female calyx has been pollinated the two white hairs turn brown and wilt but the calyx starts slowly swelling and producing the seed.

When to pollinate cannabis?

There is not a perfect time when to pollinate an autoflower cannabis female but there are some factors that can help you to know when to pollinate this plant.

First of all, we know that autoflower plants usually live no more than 2 to 3 months so we need to time our pollination graphic exactly right to get fully mature seeds. Cannabis seeds usually take a month or so to fully mature and be ready to harvest. So we need to know how long a particular strain lives and pollinate it at least a month before the end of the plant’s life cycle.

There is also a problem of too early pollination when the plants have just started flowering and the calyxes are not fully matured. If you pollinate your plant at this stage and let it grow without any further pollination then you will get a small number of seeds.

A good practice for all autoflower cannabis growers is to pollinate the plants one or two weeks into flowering. Then there are some female flowers already matured and those seeds that will form at that stage will be ready when the plant reaches it’s harvest time.

If you pollinate your plant later then those seeds may not be ready when the harvest time comes and you will be forced to let the plant grow for a longer period of time and let the THC degrade into CBN and other chemicals and forget about a top-quality bud.

How to pollinate females?

If you want to fully pollinate your autoflower female you can use either controlled or random pollination techniques.

There are some advantages to either of those methods but they both work well and it is a matter of personal taste.

Random pollination

Random pollination means that you let the plants do what they do in nature and place both male and female auto-flower plants in the same grow area and let them grow and pollinate themselves. This method requires almost no attention from the grower and it is much easier than the controlled method.

If you want to use this method then you should grow both the desired male and female strain plants in one grow room/area and let them do their magic but you definitely need to add a ventilator in that room. The fan will play the role of wind in nature and will help autoflower male pollen float through air and land on the female cannabis plant flowers.

When using this method the only thing you need to do is sit back and wait for the plants to grow. When the female plant is 3 or 4 weeks into the flowering stage you need to take out the male plant because at this point it has pollinated the female and further pollination will result in immature seeds that have no value to anyone.

When you are about to take the male plant out of the grow area you can move it at the top of the female plant and shake it in order to release more pollen and increase the seed count. Usually, the male plant will have pollinated the entire female plant but you can’t be completely sure till you harvest it and that is the reason why you should shake the male plant at the end of the pollination phase.

This method is really easy and inexperienced / beginner growers can use it to get seeds for the next crop, but this random method can’t provide all the advantages that controlled method can.

Controlled pollination

Controlled pollination is the action when you collect the male pollen and pollinate the autoflower female plant yourself.

Controlled pollination is better for experienced growers because you can fully control how many seeds you will get and what strain they will be. You can grow multiple males separate from the female and pollinate the females/female with many different strains to get different strain seeds.

When you want to control your pollination you must grow your males and females separately in order to restrain the females to get randomly pollinated by rogue pollen grains.

You need to grow the male plant until it starts flowering and collect the pollen from those matured flowers. After you have collected the pollen you can “paint” it on the female plants with a small brush.

You need to fully cover those female calyxes if you want them to form seeds because this collected pollen is not as good as the pollen that has naturally floated from a male plant.

You will need a little experience but by a third of fourth grow you will know how much pollen you need to get your desired seed amount but for new growers more is defiantly better!

This controlled pollination technique is good for breeders and seeds producers because they can control exactly what pollen gets on to a female cannabis plant and grow exactly the same strain seeds every time.

Controlled pollination is usually the choice for advanced growers and growers who want to get just some seeds and not to ruin all of their plant / plants.

Partial pollination?

The term partial-pollination means that you don’t pollinate all your plant branches but just a part of it but it can also mean partial pollination of the whole grow operation by pollination only one plant from many.

You can do the first partial-pollination with the controlled pollination method and it is usually used by new growers who want to get a nice bud but they also need some extra seeds for their next grow. Growers usually tend to pollinate the lower branches of the plant to get a good main-bud and from those lower branches, they get good seeds for next grow.

Partial pollination can also be done by experienced growers in order to get different strain male pollen on to one female plant and see what seeds are the best. This method is not so good because there can always be some pollen that lands somewhere else on the plant and ruins the whole point of this action.

The second partial pollination is more reliable from the first one and there is less chance of errors.

You need to take the female plant out of the grow area and pollinate it and then let it sit there for a day or two. When the plant has pollinated you need to blow off the unused pollen by just blowing it away and you can return the plant at your main grow area.


  1. Hi body right on target and lukly my last DNA 60 days wonder tree I have got just started to flower and I don’t know how to thank you that you made journey that endure 6 months with Thiland shwag seed ends up male and just about to mature for polinatin، nothing to lose faliure mean clean bud to me it is win win situation just like reading yr article please feel free to share good article in this nature to kdsaad@hotmail.com ،
    Thank you Mr. midowo wish u happy live ، §o¥o§ cheers

  2. I was wondering if theres any special matters for pollinating automatics. will they require ANY dark atall for seed production? cause im growing in 24 budding happy and pollinated a load of buds and they are not reacting as fast to the pollen as my photoperiods doo .. The calxys are skrinking .. but not all the way back .. not doing what i would expect (i pollinated my photo’s on the same day i did the autos and the photos have 100% worked)

    • You need to collect male pollen and with a brush carefully put it on the branches you want!

    • Few days after you see the pollen sacks they will burst open and male pollen will be ready to pollinate a female!

  3. WattSaver on

    Thanks for stopping by RIU it got me here.

    I’m working with Fem auto’s, what if I use non auto pollen, What are the odds that I’ll get an auto? I understand that the fem aspect will not come through. Just wondering about the auto aspect.

    • Hi there, tnx for stopping by.
      I cant give you an exact number but that depends on the strain and weather the autoflower trait is dominant or recessive.
      I am not an expert of breeding autoflowers but i think that autoflowerng trait usually is a recessive so you can expect non of your F1 offspring to have the auto flower trait and then cross the best of the F1 hybrids and in the second generation F2 you can have from 25% to 50% chances of autoflower trait showing. But you can also get some autoflower traits in the first hybrids, you just have to grow them out to see.
      But basically to get a stable cross there have to be at least 4 to 5 generations crossed so breeding is a very long process.

  4. As cannabis matures past the optimum harvest window, THC degrades to CBN, not CBD. Just thought you needed to know this to stop misinforming people. Cheers.

  5. Jean Kutzer on

    What is the best way to collect pollen and can it be stored? If so for how long and what method? Vacuum seal, freeze?

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