I know a lot of members are making colloidal silver to get fem seeds and I have posted in the past about tiresias mist for fem seeds. I cannot afford to buy tiresias mist all the time although it is an awesome product that works great it is not cheap. I have made a colloidal silver generator and am making some as we speak for my next pollen run. IO recently picked up a copy of high times mag and they have an article about dinafem seeds company. They talk about using silver thiosulfate to make their fem seeds. I wonder if this is what commercial growers use how many of us personal growers have experimented with is. Obviously making a coloidal silver generator is not too hard but it seems that making silver thiosulafte is even easier. The chemicals are cheap and not "controlled" so you dont have to be nervous about ordering them. The only down sides I have found via interenet research are that small amounts of the chemicals are only sold in kits by grow sites and are too expensive so you are looking at about an initial cost of 100 bucks to by in bulk at a good cost. This would supply the average grower for years and years. The other is that the precursor chemicals used to make the solution (silver nitrate, sodium thiosulfate) are mildly corrosive so you need to be careful about breathing the dust and skin contact while mixing. So what do you guys and gals think? By the way if you are interested the article of high times was the Grow Guide 2013 Special Collectors Edition. I got it last weekend at Barnes and Noble so I bet any book stores in your area still have it on the shelves.
Silver Thiosulfate solution for feminizing.
- Thread starter Salmonfisher
- Start date
The next problem is obtaining the silver nitrate. If your some were urban it may be easier as the problem with silver nitrate or nitric acid is shipping-it is controlled! So you will need to go some were that has the silver nitrate and pick it up. The government and I have gone on the go around on this and for a Cal MMJ they were okay but I would have to obtain it via an approved method and they even pointed out a few ways to pull it off. I don't know if photographic shops still have silver nitrate might try.
It looks to me and i may be wrong but if you are only buying the silver nitrate in small quantities it won't be a problem at all. You can even buy small quantities on ebay. It looks like .5 gram will make ten liters of solution which is supposed to be enough to treat 15-20 plants. Ordering ten grams online wont be a problem or shouldnt be. Again I must state that this is all me looking online at this stuff and never actually doing it so please let me know if I am wrong.
Salmonfisher you make me feel like Dorathy in The Wizard of Oz--Ebay! It is shipped by means that if they knew what was in that package---well it would not be a nice day for the guy whose name is on the return address! But since when did the USPS not wishing something sent in the mail ever stop autoflower growers?
Right along with you man, I just got 1gram of silver nitrate for $10 and 50g of sodium thiosulfate for I think $8... Got both on eBay, crazy people ship it priority mail! Free shipping on most listing and you get it ridiculously fast... Just awaiting the thiosulfate now... Than let the experiments begin... I tried the CS route and had no success my first try, got tired of making it so this is what led me to sts. I got a face mask to wear when I make it so I should be good... If you try and order it from photoforumulary they will ask you to fill out this crazy dea form which I wasn't comfortable with...have had no trouble with eBay so far...
Yodabuds
Yodabuds
https://www.autoflower.org/f8/scarhole-auto-project-15268.html#post295906
Here's the link to how i do it.
Can't get my phone to copy an paste it here?
No DEA forms required for the chems , but order them from different sources...
Here's the link to how i do it.
Can't get my phone to copy an paste it here?
No DEA forms required for the chems , but order them from different sources...
I just ordered from 2 vendors on ebay---hope the silver nitrate is legit (not contaminated with something that will render it useless.). The prices were good 5gm/$12 for silver nitrate. No questions about shipping or haz mat release--kinda like buying seeds
ive been trialing sts and made and ruined half my kitchen that stuff stains like anything and im not sure if ebay chems are legit one this is for sure buy distilled water not deionised
the silver i got seemed silver in colour but on other site it seems like clear crystals
the silver i got seemed silver in colour but on other site it seems like clear crystals
Originally Posted by MonsterDrank
Scarhole do you have a link on the STS technique? I'd love to read into it.
The industry standard is Rob Clarke's method from his advanced cannabis botany.
I use it, but I mix my Sts 1:1 with distilled water (instead of 1:6).
My friend illumination put this together.....
ATTENTION!!! ALWAYS ORDER SEPARATELY FROM TWO DIERENT SOURCES!!! YOU HAVE BEEN NOTIFIED
The following is a safe, inexpensive, and successful method for reversing the sex of female cannabis plants. Individual plant responses may vary based upon strain, but I can verify that this process is fully effective in stimulating profuse staminate flower production.
This process can be used to:
A: create new feminized seeds from solitary prize mothers that you currently have
B: create interesting feminized-seed hybrids from different prize strains that you currently have
C: create feminized seeds for optimum outdoor use
D: accelerate the "interview" phase of cultivation, in searching for interesting new clone-mothers
E: reduce total plant numbers- great for medical users with severe plant number restrictions
F: increase variety, by helping to create stable feminized seedlines to be used as an alternative to clones[\b]
At the bottom of this post are some specific details about the chemicals used, their safety, their cost, and where to get them.
It is important to educate yourself about cannabis breeding theory and technique prior to using a method like this one. Here is a link to Robert Clarke's "Marijuana Botany", which is a very good reference.
http://planetganja.net/Ebooks/Marijuana Botany.pdf
It is also important to use basic safety precautions when mixing and handling these chemicals, so read the safety data links provided. The risk is similar to mixing and handling chemical fertilizers, and similar handling procedures are sufficient.
Remember: nothing will ever replace good genetics, and some of your bounty should always go back towards the professional cannabis breeders out there... the ones who have worked for many generations to come up with their true-breeding F1 masterpieces. Support professional breeders by buying their seeds. Also, order from Heaven's Stairway. Not that they need a plug from me, but they are very professional and provide very fast service worldwide.
Preparation of STS:
First, a stock solution is made. It consists of two parts (A and B) that are initially mixed separately, then blended together. Part A is ALWAYS mixed into part B while stirring rapidly. Use distilled water; tap water may cause precipitates to form.
Wear gloves while mixing and using these chemicals, and mix and use in a properly ventilated area. A mask will prevent the breathing of any dust, which is caustic. STS is colorless and odorless, and poses minimal health risks if used as described here. (See material safety data sheet links below). Note that silver nitrate and STS can cause brown stains upon drying, so spray over newspaper and avoid spilling.
Part A: 0.5 gram silver nitrate stirred into 500ml distilled water
Part B: 2.5 grams sodium thiosulfate (anhydrous) stirred into 500ml distilled water
The silver nitrate dissolves within 15 seconds. The sodium thiosulfate takes 30-45 seconds to dissolve.
The silver nitrate solution (A) is then mixed into the sodium thiosulfate solution (B) while stirring rapidly. The resulting blend is stock silver thiosulfate solution (STS).
This stock solution is then diluted at a ratio of 1:9 to make a working solution. For example, 100ml of stock STS is added to 900ml of distilled water. This is then sprayed on select female plants.
Both the stock STS and the working solution should be refrigerated after use, as well as the powdered chemicals, to avoid activity loss. Excess working solution can be safely poured down the drain after use (with ample running water) with negligible environmental impact. It's pretty cheap.
Each liter of stock STS will make ten 1-liter batches of working solution of STS. With the minimum amount of base chemicals ordered from Photographer's Formulary (see link below), this means that each 1-liter bottle of working solution STS costs less than 9 cents, and can treat 15-20 mid-sized plants. That's 200 1-liter batches of STS for $18. Note that the distilled water costs far more than the chemicals.
Application:
The STS working solution is sprayed on select female plants until runoff. Do the spraying over newspaper in a separate area from the flower room. You probably won't smell anything, but ventilate anyway. You now have what I call a "F>M plant"; a female plant that will produce male flowers.
After the F>M plant dries move it into 12/12 immediately. This is usually done three to four weeks prior to the date that the target (to be pollinated) plants will be ready to pollinate. Response times may vary slightly depending upon the strain. More specific times can be determined by trial with your own individual strains. In my trials it took 26 days for the first pollen. 30-35 days seems optimum for planning purposes.
So, assuming that a target plant needs 3-4 weeks to produce fully mature seeds, a strain that takes 8 weeks to mature should be moved into flower at about the same time as the female>male plant. A target plant that finishes flowering in 6 weeks needs to be moved into flower later (10 days or so) so that it doesn't finish before the seeds can fully mature.
A seeded individual branch can be left to mature on a plant for a bit longer, while harvesting the other seedless buds if they finish first. Just leave enough leaves on for the plant for it to stay healthy.
Effects:
Within days I noticed a yellowing of the leaves on the F>M plants. This effect persisted for two weeks or so; after this they became green again, except for a few of the larger fans. The plants otherwise seemed healthy. No burning was observed. Growth stopped dead for the first ten days, and then resumed slowly. No stretch was ever seen. After two weeks the F>M plants were obviously forming male flower clusters. Not just a few clusters of balls, but complete male flower tops. One plant still formed some pistillate flowers, but overall it was predominantly male.
It is strange indeed to see an old girlfriend that you know like the back of your hand go through a sex change. I'll admit that things were awkward between us at first.
When the F>M plants look like they may soon open and release pollen, ( 3-1/2 to 4 weeks) move them from the main flower room into another unventilated room or closet with lighting on a 12/12 timer. Don't worry too much about watts per square foot; it will only be temporary.
When the pollen flies, move your target plants into the closet and pollinate.
A more controlled approach is to isolate the F>M plants in a third remote closet (no light is necessary in this one, as they are releasing pollen now and are nearly finished anyway). In this remote other closet the pollen is very carefully collected in a plastic produce bag or newspaper sleeve and then brought back to the lighted closet, where the target plants are now located. If this is done, be careful to not mix pollen types by letting the F>Ms dust each other. Avoid movement, or use yet another closet.
Take special care to not let pollen gather on the outside of this bag- a static charge is sometimes present. Drop small open clusters of blooms inside and then close the bag at the mouth and shake. Important: next, step outside and slowly release the excess air from the bag, collapsing it completely, so that pollen doesn't get released accidently. Point downwind; don't let it get on your hands or clothes.
This collapsed pollinated bag is now very carefully slipped over only one branch and is then tied off tightly at the mouth around the branch stem with a twist tie or tape, sealing the pollen inside. Let the bag inflate slightly with air again before sealing it off, so the branch can breathe. This technique keeps the entire plant from seeding. Agitate the bag a bit after tying it off to distribute the pollen. Don't forget to label the branch so you know which seeds are which. Other branches on this same plant can be hit with different pollen sources.
If no lighted closet is available, the plant can be moved back into the main room, but- be very carefulollen is sneaky. After 4-5 days, the bag is gently removed and the plant completes it's flowering cycle.
Yet another method has worked well for me. I position the target plants in a non-ventilated lighted closet, and then I collect pollen on a piece of mirror or glass. This is then carefully applied to the pistils of one pre-labeled branch by using a very fine watercolor paintbrush. Care is taken to not agitate the branch or the pollen. No sneezing. The plant needs to be in place first; moving it after pollination can shake pollen free and blow this technique.
Regardless of technique, at completion you will have feminized seeds. Let them dry for 2-4 weeks.
About the chemicals:
Silver nitrate is a white crystalline light-sensitive chemical that is commonly used in photography. It is also used in babies' eyes at birth to prevent blindness. It can cause mild skin irritation, and it stains brown. Avoid breathing. I didn't notice any smell or fumes, but ventilation is recommended. Be sure to wash the spray bottle well before you use it elsewhere; better yet: devote a bottle to STS use. A half gram is a surprisingly small amount; it would fit inside a gel capsule.
__________________________________________________ __________________________________________________ ________________________________________
.preparation of silver thiosulfate (sts) solution
silver thiosulfate (sts) is commonly used to block the action of ethylene in plant cell cultures. Ethylene is a hormone that is present in the gaseous state. Ethylene increases during senescence and ripening, and has been shown to increase in plant cell cultures due to wounding or the presence of auxins. Silver nitrate may be used alone to block the action of ethylene but it is not transported as well as sts thus is seldom used alone.
Prepare a 0.1 m sodium thiosulfate (sts) stock solution by dissolving 1.58 g of sodium thiosulfate (product no. S 620) into 100 ml of water. Prepare a 0.1 m silver nitrate stock solution by dissolving 1.7 g of silver nitrate (product no. S 169) into 100 ml of water. Store the stock solution in the dark until needed to prepare the sts.
The sts solution is prepared with a molar ratio between silver and thiosulfate of 1:4, respectively. Nearly all of the silver present in the solution is in the form of [ag (s2o3)2]3-, the active complex for ethylene effect inhibition.
Prepare a 0.02 m sts by slowly pouring 20 ml of 0.1 m silver nitrate stock solution into 80 ml of 0.1 m sodium thiosulfate stock solution. The sts can be stored in the refrigerator for up to a month. However, preparation of the sts just prior to use is recommended.
__________________________________________________ __________________________________________________ ________________________________________
A SIMPLE SAFE AND INEXPENSIVE FEMMING METHOD
LINKS TO THE CHEMICALS:
sodium thiosulfate
http://www.bhphotovideo.com/c/produc...Anhydrous.html
Silver Nitrate
http://secure.sciencecompany.com/Sil...10g-P6503.aspx
ATTENTION!!! ALWAYS ORDER SEPARATELY FROM TWO DIERENT SOURCES!!! YOU HAVE BEEN NOTIFIED
Scarhole do you have a link on the STS technique? I'd love to read into it.
The industry standard is Rob Clarke's method from his advanced cannabis botany.
I use it, but I mix my Sts 1:1 with distilled water (instead of 1:6).
My friend illumination put this together.....
ATTENTION!!! ALWAYS ORDER SEPARATELY FROM TWO DI
ERENT SOURCES!!! YOU HAVE BEEN NOTIFIED The following is a safe, inexpensive, and successful method for reversing the sex of female cannabis plants. Individual plant responses may vary based upon strain, but I can verify that this process is fully effective in stimulating profuse staminate flower production.
This process can be used to:
A: create new feminized seeds from solitary prize mothers that you currently have
B: create interesting feminized-seed hybrids from different prize strains that you currently have
C: create feminized seeds for optimum outdoor use
D: accelerate the "interview" phase of cultivation, in searching for interesting new clone-mothers
E: reduce total plant numbers- great for medical users with severe plant number restrictions
F: increase variety, by helping to create stable feminized seedlines to be used as an alternative to clones[\b]
At the bottom of this post are some specific details about the chemicals used, their safety, their cost, and where to get them.
It is important to educate yourself about cannabis breeding theory and technique prior to using a method like this one. Here is a link to Robert Clarke's "Marijuana Botany", which is a very good reference.
http://planetganja.net/Ebooks/Marijuana Botany.pdf
It is also important to use basic safety precautions when mixing and handling these chemicals, so read the safety data links provided. The risk is similar to mixing and handling chemical fertilizers, and similar handling procedures are sufficient.
Remember: nothing will ever replace good genetics, and some of your bounty should always go back towards the professional cannabis breeders out there... the ones who have worked for many generations to come up with their true-breeding F1 masterpieces. Support professional breeders by buying their seeds. Also, order from Heaven's Stairway. Not that they need a plug from me, but they are very professional and provide very fast service worldwide.
Preparation of STS:
First, a stock solution is made. It consists of two parts (A and B) that are initially mixed separately, then blended together. Part A is ALWAYS mixed into part B while stirring rapidly. Use distilled water; tap water may cause precipitates to form.
Wear gloves while mixing and using these chemicals, and mix and use in a properly ventilated area. A mask will prevent the breathing of any dust, which is caustic. STS is colorless and odorless, and poses minimal health risks if used as described here. (See material safety data sheet links below). Note that silver nitrate and STS can cause brown stains upon drying, so spray over newspaper and avoid spilling.
Part A: 0.5 gram silver nitrate stirred into 500ml distilled water
Part B: 2.5 grams sodium thiosulfate (anhydrous) stirred into 500ml distilled water
The silver nitrate dissolves within 15 seconds. The sodium thiosulfate takes 30-45 seconds to dissolve.
The silver nitrate solution (A) is then mixed into the sodium thiosulfate solution (B) while stirring rapidly. The resulting blend is stock silver thiosulfate solution (STS).
This stock solution is then diluted at a ratio of 1:9 to make a working solution. For example, 100ml of stock STS is added to 900ml of distilled water. This is then sprayed on select female plants.
Both the stock STS and the working solution should be refrigerated after use, as well as the powdered chemicals, to avoid activity loss. Excess working solution can be safely poured down the drain after use (with ample running water) with negligible environmental impact. It's pretty cheap.
Each liter of stock STS will make ten 1-liter batches of working solution of STS. With the minimum amount of base chemicals ordered from Photographer's Formulary (see link below), this means that each 1-liter bottle of working solution STS costs less than 9 cents, and can treat 15-20 mid-sized plants. That's 200 1-liter batches of STS for $18. Note that the distilled water costs far more than the chemicals.
Application:
The STS working solution is sprayed on select female plants until runoff. Do the spraying over newspaper in a separate area from the flower room. You probably won't smell anything, but ventilate anyway. You now have what I call a "F>M plant"; a female plant that will produce male flowers.
After the F>M plant dries move it into 12/12 immediately. This is usually done three to four weeks prior to the date that the target (to be pollinated) plants will be ready to pollinate. Response times may vary slightly depending upon the strain. More specific times can be determined by trial with your own individual strains. In my trials it took 26 days for the first pollen. 30-35 days seems optimum for planning purposes.
So, assuming that a target plant needs 3-4 weeks to produce fully mature seeds, a strain that takes 8 weeks to mature should be moved into flower at about the same time as the female>male plant. A target plant that finishes flowering in 6 weeks needs to be moved into flower later (10 days or so) so that it doesn't finish before the seeds can fully mature.
A seeded individual branch can be left to mature on a plant for a bit longer, while harvesting the other seedless buds if they finish first. Just leave enough leaves on for the plant for it to stay healthy.
Effects:
Within days I noticed a yellowing of the leaves on the F>M plants. This effect persisted for two weeks or so; after this they became green again, except for a few of the larger fans. The plants otherwise seemed healthy. No burning was observed. Growth stopped dead for the first ten days, and then resumed slowly. No stretch was ever seen. After two weeks the F>M plants were obviously forming male flower clusters. Not just a few clusters of balls, but complete male flower tops. One plant still formed some pistillate flowers, but overall it was predominantly male.
It is strange indeed to see an old girlfriend that you know like the back of your hand go through a sex change. I'll admit that things were awkward between us at first.
When the F>M plants look like they may soon open and release pollen, ( 3-1/2 to 4 weeks) move them from the main flower room into another unventilated room or closet with lighting on a 12/12 timer. Don't worry too much about watts per square foot; it will only be temporary.
When the pollen flies, move your target plants into the closet and pollinate.
A more controlled approach is to isolate the F>M plants in a third remote closet (no light is necessary in this one, as they are releasing pollen now and are nearly finished anyway). In this remote other closet the pollen is very carefully collected in a plastic produce bag or newspaper sleeve and then brought back to the lighted closet, where the target plants are now located. If this is done, be careful to not mix pollen types by letting the F>Ms dust each other. Avoid movement, or use yet another closet.
Take special care to not let pollen gather on the outside of this bag- a static charge is sometimes present. Drop small open clusters of blooms inside and then close the bag at the mouth and shake. Important: next, step outside and slowly release the excess air from the bag, collapsing it completely, so that pollen doesn't get released accidently. Point downwind; don't let it get on your hands or clothes.
This collapsed pollinated bag is now very carefully slipped over only one branch and is then tied off tightly at the mouth around the branch stem with a twist tie or tape, sealing the pollen inside. Let the bag inflate slightly with air again before sealing it off, so the branch can breathe. This technique keeps the entire plant from seeding. Agitate the bag a bit after tying it off to distribute the pollen. Don't forget to label the branch so you know which seeds are which. Other branches on this same plant can be hit with different pollen sources.
If no lighted closet is available, the plant can be moved back into the main room, but- be very carefulollen is sneaky. After 4-5 days, the bag is gently removed and the plant completes it's flowering cycle.
Yet another method has worked well for me. I position the target plants in a non-ventilated lighted closet, and then I collect pollen on a piece of mirror or glass. This is then carefully applied to the pistils of one pre-labeled branch by using a very fine watercolor paintbrush. Care is taken to not agitate the branch or the pollen. No sneezing. The plant needs to be in place first; moving it after pollination can shake pollen free and blow this technique.
Regardless of technique, at completion you will have feminized seeds. Let them dry for 2-4 weeks.
About the chemicals:
Silver nitrate is a white crystalline light-sensitive chemical that is commonly used in photography. It is also used in babies' eyes at birth to prevent blindness. It can cause mild skin irritation, and it stains brown. Avoid breathing. I didn't notice any smell or fumes, but ventilation is recommended. Be sure to wash the spray bottle well before you use it elsewhere; better yet: devote a bottle to STS use. A half gram is a surprisingly small amount; it would fit inside a gel capsule.
__________________________________________________ __________________________________________________ ________________________________________
.preparation of silver thiosulfate (sts) solution
silver thiosulfate (sts) is commonly used to block the action of ethylene in plant cell cultures. Ethylene is a hormone that is present in the gaseous state. Ethylene increases during senescence and ripening, and has been shown to increase in plant cell cultures due to wounding or the presence of auxins. Silver nitrate may be used alone to block the action of ethylene but it is not transported as well as sts thus is seldom used alone.
Prepare a 0.1 m sodium thiosulfate (sts) stock solution by dissolving 1.58 g of sodium thiosulfate (product no. S 620) into 100 ml of water. Prepare a 0.1 m silver nitrate stock solution by dissolving 1.7 g of silver nitrate (product no. S 169) into 100 ml of water. Store the stock solution in the dark until needed to prepare the sts.
The sts solution is prepared with a molar ratio between silver and thiosulfate of 1:4, respectively. Nearly all of the silver present in the solution is in the form of [ag (s2o3)2]3-, the active complex for ethylene effect inhibition.
Prepare a 0.02 m sts by slowly pouring 20 ml of 0.1 m silver nitrate stock solution into 80 ml of 0.1 m sodium thiosulfate stock solution. The sts can be stored in the refrigerator for up to a month. However, preparation of the sts just prior to use is recommended.
__________________________________________________ __________________________________________________ ________________________________________
A SIMPLE SAFE AND INEXPENSIVE FEMMING METHOD
LINKS TO THE CHEMICALS:
sodium thiosulfate
http://www.bhphotovideo.com/c/produc...Anhydrous.html
Silver Nitrate
http://secure.sciencecompany.com/Sil...10g-P6503.aspx
ATTENTION!!! ALWAYS ORDER SEPARATELY FROM TWO DI
ERENT SOURCES!!! YOU HAVE BEEN NOTIFIED
Silver nitrate should be a white crystal or powder. It can decompose leaving silver behind. It is dense-heavy feel to it. Dissolve a little in water and a sprinkle of table salt and a white colloid should form-the white minute particles will never settle out of the solution no matter how long you let it sit.
