Since professional growers produce feminized seeds, I decided to research how they did it. There were a few different ways suggested, but the one that interested me the most was using colloidal silver. Some articles said this is the main way seed growers develop feminized seeds and/or "self" the plant.
HOW TO USE COLLOIDAL SILVER TO PRODUCE FEMINIZED SEEDS
A very basic description of colloidal silver and it's actions: It is a solution of pure silver particles suspended in distilled water. It is often taken orally for health benefits (easy to purchase). When used on marijuana plants, it inhibits ethylene production needed (and normally produced) by the plant to produce female flowers, thus forcing the plant to produce male pollen sacs instead. Since there are no male chromosomes, the pollen is female (listed in many places as 99.99% female) and will produce female seeds.
CAUTION: First be completely aware that any part of a plant that you spray with colloidal silver IS NOT SAFE FOR CONSUMPTION (smoking or ingesting). The pollen created is completely safe to use and all seeds created with that pollen are safe.
BE SAFE!!! For this reason, I highly recommend using a complete plant (small clone or plant) to produce your pollen. Separate this plant from all other plants so you do not get colloidal silver spray on any consumable plants.
What you will need:
1) Colloidal Silver (CS) Spray (at least 40 ppm and pure - not too strong either!) and a spray bottle. I purchased Bio-Silver Ultra Colloidal Silver 50 ppm online and it worked.
2) One female plant to turn male. From seed or clone doesn't matter - but it should be the best looking female with all the characteristics that matter to you, since it will be used as a parent for your seeds. This can be a small plant in a small pot.
3) One female plant to pollinate. You can pollinate just a few flowers on a branch (do not use bottom flowers because they may not produce finished seeds), an entire branch, or the entire plant.
The day before you change your light cycle to 12/12, you will begin to thoroughly mist all new growth areas with the CS spray on the plant you wish to turn male. Repeat this at least once daily until you see male pods forming (use magnifying glass to watch closely - approximately 10 to 21 days). If the plant begins developing flowers quickly (as with auto-flowering strains), spray 2 to 3 times daily (dependent upon the plant's tolerance of the solution) until you see male pollen sacs forming where female flowers were developing). Once daily is the recommendation unless otherwise needed. Be sure to store your CS in a dark place between uses as light can degrade the CS solution. AND REMEMBER TO AVOID SPRAY TOUCHING CONSUMABLE PLANTS!!!
Once you are sure male sacs are developing, separate this male plant from your females to avoid accidental pollination. I simply took my female-turned-male plant to a different room with no air movement and let it survive on window light. A closet with a CFL would do nicely too. Heat and moisture are pollen killers, so avoid hot or moist areas.
Once male sacs begin to develop on the plant, it will be a bit of time before the majority of the sacs open to release pollen. With the auto strain I did, it was about 2 weeks, but this time varies with different strains. Don't disturb this plant (no air flow) and simply wait for numerous pollen sacs to open. Even the slightest air draft carries the pollen adrift... but it also makes it so very easy to collect too! When numerous pollen sacs are open, a gentle tap makes the pollen easy to collect on any clean smooth surface like glass or a mirror. It will be slightly yellowish in color. Use immediately, or dry and freeze for later use.
Need I say it is very important to change clothes and wash yourself completely before re-entering your flowering room!!! Pollen is very small and clings to clothing, hair, etc very easily.
Now, if you prepared ahead, you will also have a female plant flowering very nicely by the time you have your pollen. Isolate the plant, or branch, and pollinate. This info isn't geared towards detailed pollination methods, so please check other sources for that information. I used a Q-tip and tapped it gently over the flowers I wanted to pollinate.
Allow the female plant (or branch) adequate time to finish producing viable seed. If you take her early, your seeds will not be viable. The time needed for viable seeds varies with different strains and can range from 3 to 6 weeks with an average of 4 to 5 weeks.
Wah-lah... you now have feminized seeds... at least that's what the info said SHOULD happen!
Last... my own experience...
Before deciding to try colloidal silver, I had already purchased 10 regular (not feminized) auto-flowering seeds because I wanted to be able to have male pollen to use to create my own seeds. After planting those seeds, I got to reading about CS and decided to try this too.
Nine out of ten seeds came up. My biggest concerns were that I couldn't simply start spraying the day before light change because I didn't have feminized seeds and the strain is auto-flowering. I knew I would have to wait until the plants showed their sex and worried it wouldn't work because I couldn't start it soon enough and autoflowering plants go direct into flowering once they preflower.
I ended up with 5 females and 4 males. I watched closely for preflowers and identified the females as quickly as I could. I saved the two best males in case the CS didn't work. I did find out it is very easy to collect pollen with those first males... and I did pollinate a female just to assure I would have seeds and the CS procedure wasn't finished by the time the true males pollen was.
I took the largest and best looking female and began to spray her once daily as soon as she clearly showed preflowers. But since this is an auto flowering plant, she began to grow small hairy flowers in the first few days. I increased to spraying the new growth areas (basically small flowers beginning in all nodes) to 2 to 3 times daily for the next 10 days, but this solution is pretty hard on the plant. When I began to feel I was seeing changes (looking at thru 20x magnifying glass), I decreased to once daily again for the remainder of the 21 days it took to have this lil lady turn male.
She put up a good fight. She kept shooting out hairs everywhere and I kept spraying them, which ultimately killed them and turned those female pods into male sacs. I am not at all concerned about hermie traits because she was definitely all girl being forced to grow balls. But balls she did grow in the end! I will also say, her leaves were shriveled pretty bad and her growth was definitely stunted with this procedure - but she ended up giving me all the pollen I would ever need for this strain.
Since it worked with an auto-flowering strain, I have now taken 2 clones from each of the non-auto strains I have vegging (I prefer pure strains, not cross-strains). I will use one to create a small male and the other as a small female to flower. Won't need to put them in anything but small pots, won't take up too much room, can remove from the room easily for safe pollination... and will sure give me nice returns with pure strains seeds I can pop anytime I want!!!
I hope others find this useful too - because I am in no way a professional!! If I can do it, so can others!