It's when the seedling is in its first few weeks of growth. I would think it's pretty obvious that I wasn't trying to say that exposing the ungerminated seed to red light would effect it's sex. There are quite a few examples of organisms that have an early development phase where outside environmental factors influence the sex.
sry, wasnt obvious to me. even jorge cervantes once claimed shining red light on seeds from their pack will change some to females. from there the red lighters came stomping through the crowds of yesteryear.
techniques like this rodelization guarantee fem seeds without the cost of growing rooms of herms, red light guesswork only to have to plant all those red light seeds just to see if it worked right seems strange to me.
anyone growing for female seeds uses chemicals or rodelization as explained here by Soma
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I named this new method "Rodelization," after a friend who helped me realize and make use of this way of creating female seeds. After growing crop after crop of the same plants in the same conditions, I noticed that if I flowered the plants 10-14 days longer than usual, they would develop male "bananas." A male banana is a very slight male flower on a female marijuana plant that is formed because of stress. Usually they do not let out any pollen early enough to make seeds, but they sometimes do. They are a built-in safety factor so that in case of severe conditions, the plant can make sure the species is furthered.
To me, a male banana is quite a beautiful thing. It has the potential of making all female seeds. Many growers out there have male-banana phobia. They see one and have heart palpitations, they want to cut down the entire crop, or at the very least take tweezers and pluck the little yellow emergency devices out. I call them "emergency devices" because they emerge at times of stress.
In the Rodelization method, the male banana is very valuable. After growing your female plants 10-14 days longer than usual, hang them up to dry, then carefully take them off the drying lines and inspect for bananas. Each and every banana should be removed, and placed in a small bag labeled very accurately. These sealed bags can be placed in the fridge for one or two months and still remain potent.
For the next phase, you need to have a separate crop that’s already 2 1/2 weeks into flowering. Take your sealed bags of pollen out of the fridge, and proceed to impregnate your new crop of females. To do this, you must first match the female plant and the pollen from the same strain in the previous crop. Shut all the fans in the growroom down. Then take a very fine paintbrush, dip it in the bag of pollen, and paint it on the female flower. Do this to each different strain you have growing together. I have done it with up to 10 different kinds in the same room with great success.
I use the lower flowers to make seeds, leaving the top colas seedless for smoking. This method takes time (two crops), but is completely organic, and lets you have great-quality smoke at the same time you make your female seeds. If you’re one of those growers who’s never grown seeds for fear of not having something good to smoke, you will love this method.
You can also use this pollen to make new female crosses by cross-pollinating. The older females with the male bananas can be brought into the room with the younger, unpollinated females after they are three weeks into flowering. Turn all of the circulation fans on high, and the little bits of pollen will proceed to make it around the room. Do this for several days. Six to seven weeks later, you will have ripe 100% feminized seeds; not nearly as many as a male plant would make, but enough to start over somewhere else with the same genetics."