Feminization of Seeds using Gibberellin (GA3)

Gibberellins (GAs) are plant hormones that regulate various developmental processes, including stem elongation, germination, dormancy, flowering, flower development and leaf and fruit senescence.[1]

I wanted to feminize some seeds as an experiment. My local hydro store suggested gibbarellin as a means to turn the female plant to male to produce pollen. So I ordered some gibbarellin fro flea bay to begin my trial. The gibberellin came with a 0.15g measuring spoon. To prepare a 300PPM solution I first dissolved a spoon full of gibbarellin in 15 mls of ethanol (gibbarellin won’t dis love well in water) following dissolution I further diluted in 500mls of water in a spray bottle.

I started to spray a branch of each of my plants at the time I flipped to 12/12. I have two plants currently running in DWC: Black Indica and Bubble Gum. I used a paper bag flattened as a spray shield so only one branch of each plant sees the treatment. I have been treating daily 1-2hrs after light on.

I started spraying Monday (3/25) so things are very early but there is noticeable elongation for the branches that are being sprayed. With the BG branch there is noticeable changes taking place.

With Black Indica it is less noticeable, but I am seeing some elongation.

I will continue to report as new developments occur.


Nice i did colloidal silver and took almost 3 weeks of spraying. I also had 2 that i started spraying 1 week before putting in the flower tent and they flipped alot faster. Im very interested in what your doing never heard of the stuff your using. Set to watching now

NIce, I read in another post about you starting this. Thanks for making a thread on it.

Is there any you tube videos using this stuff it seems to be like the secret ingredient to the bbq sauce when making feminized seeds i guess there’s a learning curve on everything i got got pollen pods going but i don’t know if i will have enough time to get seeds out of the others because i put everything in flower at the same time thinking it would be just like outside but now rethinking that idea but saving the pollen for later when want to do crosses

I’m jealous. I grew up around where you’re at, and I miss all the good BBQ.


Only found a few references on use of gibberellin but it has been shown to create male flowers on female plants. While I don’t have the equipment necessary to fully control the delivery, there are products that out there that are being sold with GA3 (SeedFem). Here is a scientific reference showing it works:

Some have mentioned 100PPM at or just before flowering as the level necessary, I have no idea the potency of the GA I got off of eBay. Says 90% but who knows what you are getting off the old flea bag. Also, supposedly GA3 is not very stable in water. So I arbitrarily said let’s do 300PPM. Hopefully I don’t under shoot or over shoot the potency requirement because I will not have any idea why it didn’t work. Just throwing darts at the moment. Have no idea whet the board looks like.

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Im using 50 ppm colloidal silver

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Yeh they got asprin from the willow tree @WickedAle

@Hungrybud Almost, salasylic acid is derived from willow trees and has an analgesic properties, but they found it to be too bitter and irritating so they modified it with acetic acid(vinegar) to create acetylsalasylic acid.

Yes they use the bark of the willow tree as an alternative to asprin, also fermented willow tree juice is good for watering clones just like coconut water.

Great to see a good success using that medium. Nice

Is there a plant key or something like that. Like skunk cabbage makes and holds silica and and this grass is a good nitrogen holder. I find garden site’s but not the information im looking for. Like to know this information to make a tea out of the stuff that is already growing around me. It would list the plant have it’s c to n ratio and what it holds in it . Is there something like this out there im trying to learn as much as possible on this. Or find a resource on the net somewhere

Yeh if the locals had back pain they would chew on the bark of the willow, same process as the leaves on the olive tree, the locals chew on the leaves to ward off colds and flu, you can purchase Olive leaf extract made from the leaves.

Day 12 update

Plants have now been on a 12/12 lighting schedule and I have treated with the 300PPM GA3 solution for 12 consecutive days. I will now discontinue the GA3 treatment.

Noted changes:

  • Elongation has continued. With BG the lower branch is not as tall as the top cola. With BI the elongation seems to be not only with the treated branch, but to the entire area of the treated branch.
  • Yellowing of the branch (not as apparent with BI).
  • Elimination of the Female characteristics although it’s tough to say I see male characteristics.

General view of the plants with treated branch indicated:

Comparison of Bubble Gum Treated to Untreated branches



Black Indica treated

@Bogleg tagging you in. What do males in flower look like? Anything familiar with the treated branch?


I was trying to find a picture but I don’t appear to have any handy.

The males will show themselves before the females. The little balls will form pretty shortly after the flip to 12/12.

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Found one!


@Bogleg so a big maybe so far. Another week will probably tell.

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WEEK 3 Update

Well I am losing hope over GA3 feminization at the concentrations and treatment times I’ve used.

Black Indica
Even though I only sprayed on 1 small branch, it seems the GA3 was absorbed and internalized into the entire plant and is showing profound stretching on the side of plant that the branch was on. Even though I have been 12/12 for 3 weeks I still have not seen white pistils on any of the plant (although it does seem close.) There are no male structures on the treated branch. The region of the treated branch has stretched 6”taller than the rest of the plant. Plant is now lopsided having a low and a high side.

Bubble gum
Only the treated branch has stretched but now is 6” taller than the rest of the plant. I do not see any male structures on the treated branch.


My colloidal silver didn’t do anything like that. That is very weird mine stayed the same growth wise and the female buds made flowers wit pollen. I wonder if you got gipped on this because in 3 weeks you should of already had pods at least small ones
This is my sugar black rose


@ThcinKC The gibberellin definitely had an effect and is widely known to cause stem elongation. From the literature it also was reported to cause feminization. I could not really find a good procedure using the eBay gibberellin and was sort of winging it. Should have used a more tried and true method using silver nitrate or colloidal silver, but I also wanted to see the effect of GA3 on the plant as it may have other usages. So it’s not a total loss, just hope my black indica blooms properly though.