Germinating with Rockwool??? First timer

Discussion in 'First Time Marijuana Growers' started by Floweroflife, May 12, 2010.

  1. Hey Everybody,
    I am using rockwool for the very first time and was wondering the easiest way but the most successful all in all way. Is it best to use the paper towel method and then transplant the seedlings into the rockwool? If anyone can guide me step by step it would be a HUGH help....Peace:D
  2. what up flower!
    i germ mine in paper towel to ensure a good tail and a good germ..
    then i soak my plug's in r/o ph of 6.9-7.0 water (or adjusted tap)for a few hour's or overnight depending on how stoned i
    then sqeeze all of the water out and resoak in fresh r/o water..
    this will get your ph closer to 7 rather than the 5.5 or lower that rockwool usually comes need's to be flushed out..
    i make it ph nuetral basicly..but it does still drop a little after the rinse..just right!,,
    then i pop my seed's in alway's with the tail down first..
    i put cubes in a tray with about a 1/4 inch of water in the bottom of that pan to keep them babies moist until they fully germ from the cubes..
    rockwool will dry fast once it start's..this just keep's that from happening , kinda a fail safe..
  3. Yes go with the paper towel method to start off with, once the seed breaks then transplant it to the rockwool. A steady hand helps. The seed goes in with the root facing the bottom so that the seed shell is pointing upwards. In the meantime presoak your rockwool with water at 7.0 pH for 24 hours.
  4. #4 JollyStoner, May 12, 2010
    Last edited by a moderator: May 12, 2010
    You're actually supposed to pre-soak your rockwool in 5.5 PH water... and only for about a minute or two... not 24 hours.

    I soak my seeds in water (drinking/distilled or RO water preferred) for 24 hours then drop them straight in the rockwool and put it over a heating mat with a dome on top. The heating mat has a thermostat set to 80 degrees F.

    I grow cannabis, tomatoes, peppers, and all sorts of vegetables. Almost every single seed planted this way germinates perfectly. There is no need to wait for the seed to germinate before dropping it into the rockwool nor is there any reason to position the seed in any way (especially if you germinate straight in the rockwool like I do) it will find its way up.. trust me.

    EDIT: Not trying to say the previous posted methods are wrong. I just find that I have a higher success rate doing what I described.
  5. #5 custom280Z, May 12, 2010
    Last edited by a moderator: May 12, 2010

    oooooook! , you put seed's in rockwool upside down and they struggle to get to the surface....been proven..
    tail's down is something that's ben done over and over by many grower's for many years..
    never in my life have i read on the side of rockwool to only soak for a few minutes..that's not going to properly flush it at all..that and when you soak rockwool that is low in ph with just as low of a ph water the ph drop's over time or drop's ph in your res..making it closer to a ph neutral is better for hydro system's or transplanting to soil at the same time! plus the rockwool it self will slightly buffer down the ph, ph is not as important for germing and cloning as it is for later growing in a hydro or soil your success germing really can't put a thumb on the best techniques..i mean after all they will germ if you just toss them in the yard..i mow several a just sittin on the portch and rollin one up and toss that they are a hearty plant ..
    this is why very great medium's like coir, sure to grow etc..come pre ph neutral homie..
    easier to adjust any system later, or to put straight into soil..
    heat mat's dry out rockwool and are a 20 dollar or more waist of time and are humidity domes..i've seen about 20-30 newer grower's dry out seedling's in soilless medium with the use of a heat is may as it is..(almost summer)
    unless your grow room temp's are lower than 68-66 degrees there is no need for one..
    another simple fact..
    you may not know..
    when you germ seed's at lower temp's the ratio of females to males goes up!
    heat mat's are insurance for males when growing non fem's..

    i've only been doing this for 26 years
    and i was born and raised on a big horticulture nursery, i grow allot more than veggies and mj..
    And i said soak in ph adjusted water for a few hour's or you can leave it soaking for 24 hour's...not just soak it for 24 hour'
    a few minutes and not squeezing it it and resoaking, deos not cut it in my hydro setup's here...
    all because something work's for you, does not make it the best or most efficient way ..
    not saying your way is bad, wrong or horrible, just not the best ..
    but we all do thing's differently, i've just had some time to actually test theories side by side and growing techniques ..
  6. #6 JollyStoner, May 12, 2010
    Last edited by a moderator: May 12, 2010

    First off.. Rockwool does NOT lower PH it actually RAISES PH due to the lime.

    Secondly, Im talking about little 1 inch STARTER PLUGS like the GRODAN AOK Plugs.. Those only need a few minutes of soaking at most. Even says it right on the label. When you transfer to the LARGE blocks, then those large ones need to be soaked in 5.5 PH water to neutralize the lime in the rockwool overnight.

    Third.. Seeds dont struggle one bit to make it up a quarter to half inch hole. I germinate THOUSANDS of seedlings every month for our plant nursery without ever worrying about planting tail down. I am also a medical grower and germinate cannabis seeds exclusively and create my own clones rather than bring in clones from the outside to maintain sanitary conditions.

    Fifth... Although alot of cannabis seeds will germinate at lower temps, certain strains actually REQUIRE a temperature closer to 80 degrees and certain few even above 80 to successfully germinate. 78 Degrees Fahrenheit is the OPTIMAL germination temperature for a higher success rate and setting your thermostat to 80 will keep it fluctuating between 75 and 80 degrees.

    When you spend big bucks on seeds you want to make sure you have a higher germination rate so a $15 heating mat is a very small investment to ensure your $10 (per) seed germinate. And NO, a heating mat does NOT dry out the cubes ESPECIALLY if you use a dome.. all this can be bought very cheap.

    Sixth.. The only time PH becomes a factor is if the grower chooses to use the large rockwool blocks sitting in an Ebb and Flow system where the block becomes soaked and the nutrient water drains back into the reservoir. Any other method such as DWC, NFT, Aeroponics, etc.. the rockwool doesnt even touch the water. It is surrounded by hydroton and the roots grow through and hang away. The tiny 1 inch rockwool becomes very insignificant and in soil it is too tiny to do anything either.

    Again, like I said before.. those other methods are not wrong and I did not claim to have the "Best" method. What I described is the method I used and have been very successful doing so. Feel free to add your own ideas and let the OP decide what he wants to do.
  7. #7 JollyStoner, May 12, 2010
    Last edited by a moderator: May 12, 2010
    By the way... professional growers who germinate thousands of seeds in a nursery are not going to sit there and make sure every seed is growing tail down. Those plants all do just fine, same applies to cannabis seeds.

    All these tomatoes were started in rockwool cubes then transferred to soil:

    • Like Like x 1
  8. firts of all lol..
    who are you to say this? are you survey taker on all pro nusery worker's?
    cause i was born and raised on one homie..
    and yes people that do take pride in there work do those little thing's to ensure the seed does not try to grow the wrong direction in a rockwool cube, plug or obviously just lack pride in your work..or reading cause that sit is even in growbook's etc..
    it's an insurance..

    secondly this is grass city, not tomater
    growing veggies get's you know where my flower room hold's more mj than that pic's got in who cant grow tomatoes really???

    third.. i use grodan! i do test studies for them, hydrodon and f'n sure grow! lol
    show's what you know..

    forth, you skipped this one lol it comes after 3

    rockwool is made of lava rock broken down and spun like wool...
    it is not ph balanced and no were do i see lime..
    lime is bad for hydro system's bro, i seriously dought rockwool would have very or little lime in it..seeing as it is mainly based in hydro..and if any real lime was present it would not have such a low ph to begin with...or flux in ph for you in only a few minutes..
    not only that rockwool is about garbage compaired to any other growing medium...perlite is even better than rockwool..

    6th lol
    i love your take on heat mat's seeing how i just helped a guy who dried his cubes out overnight and killed his expensive seed's..
    they will dry out cubes if not's a fact! not a myth..
    not my first rodeo bro..
    all i buy are expensive seed's and great genetic'
    geez i'm only a breeder! lol

    "Sixth.. The only time PH becomes a factor is if the grower chooses to use the large rockwool blocks sitting in an Ebb and Flow system where the block becomes soaked and the nutrient water drains back into the reservoir. Any other method such as DWC, NFT, Aeroponics, etc.. the rockwool doesnt even touch the water. It is surrounded by hydroton and the roots grow through and hang away. The tiny 1 inch rockwool becomes very insignificant and in soil it is too tiny to do anything either"

    this is bullshit to the 10th degree...
    do you grow hydro bro?
    ok i never surround a medium with a different one..i either go all rockwool or all hydrodon or all sure to grow..
    i use dwc, bubble bucket's, ebb and flow and a hybrid aero/dwc system(cloner) is the main thing you have to watch in any hydro setup man! that and ppm..:eek:
    ya i agree that 1 cube might not have that much effect...but who uses only one cube in any dro setup???
    really?? i have 24 in my cloner..24 plug's not properly adjusted and drained then readjusted to a proper ph will f'k my whole system sideway's man...
    those little cubes do add up...
    and with dwc, aero and all the rest..water from the res still get's circulated through the cube ...especailly aero..then it drains across and down the root's into the res...
    most all system's circulate that water through those cubes man...almost all..
    even dwc...
    it does not just sit in there dry or
    but instead of mater pic's..

  9. #9 JollyStoner, May 12, 2010
    Last edited by a moderator: May 12, 2010
    My bad.. you got me on the counting.. I edited my post and accidentally cut 4th out..

    I know this is "grasscity" and like I said.. I dont just grow tomatoes... I grow Cannabis too. You know so much about rockwool you still didnt mention why you said it lowers PH.

    KGS--Riley and Geary County Geology--Economic Geology

    Rockwool does contain lime when processed. Read the above link and feel free to google it.

    Maybe YOU dont surround your rockwool with hydroton but ALOT of growers do. Most growers start a seed or clone in some sort of a plug then surround it with hydroton.

    I never said its PH Balanced.. I said it raises PH. (you said the contrary)

    I never mentioned anything about ONE single rockwool cube in a hydro setup.. again you're making shit up (scroll up and read).

    And NO, most methods dont drain through the rockwool enough to pass anything and again with the small cubes as long as they are dipped in 5.5 ph water for a short while its safe. Like I said, its the big cubes that need to be dipped longer.. yet again you missed that part.

    If you dry out your rockwool overnight on a heating mat with a thermostat and a plastic dome on top under high humidity then there is something wrong with you and you shouldnt be growing anything.
  10. #10 custom280Z, May 12, 2010
    Last edited by a moderator: May 12, 2010
    i was just f'kn with ya on the counting thing bro...laugh it was

    ya it's right there bro i'll quote ya..
    "The tiny 1 inch rockwool becomes very insignificant and in soil it is too tiny to do anything either"
    i guess i did read after even sais "either" at the end..meaning hydro or soil..

    i never said rockwool was ph balanced..i said to go through the soaking proccess to make it ph nuetral and ph balanced are two different thing's homie..
    if it's ph neutral then a hydro system will adjust it's ph with the water and nutes..
    you can clearly see water going to and driping from the obviously have no clue how an aero system or any kind of cloning machine work's..[​IMG]

    clones don't root without the water and nutes going into the rockwool someway or form...
    and almost every single system i've ever seen hydro wise look's either spot on to this system or straight dwc and it all get's water bro...even in dwc the violent bubbles coming up to the surface just an inch or two below the pot splash water to the rockwool or hydrodon..not to mention how much get's wicked to it by the root's alone..
    anyone here at gc got dry medium in there hydro setup??

    didn't think so..
    oh and i build all my pro setup's my self as well...i have a very good understanding how they work man...just ask somebody!

    like i asked before though you even grow hydro?
    got no answer or pic's...beat right around that question..
    that kinda makes all the difference between bookworming and experience..
  11. and a little something about ph...all other medium's like coir, perlite, vermiculite, sure to grow, hydrodon i need to name any more???
    are ph nuetral right from the bag and need no flushing to adjust ph like rockwool...
    why do you think this is.....hmmmmm...because it's best for all system's..and that's why
    rockwool is f'n day's ..
  12. #12 JollyStoner, May 12, 2010
    Last edited by a moderator: May 12, 2010
    Yes it was funny.. I'll give you that..

    Again you are missing my point man... Let me make it perfectly clear:


    so you can have a hundred of those in your cloner and you will be safe once it is neutralized.

    Here's the manufacturer's recommendation:

    Hydroponics - How to condition Rockwool

    The mini plugs are ok to just dip and not leave overnight!

    Im not disagreeing with you on soaking the rockwool overnight but im clarifying that you need to soak the larger ones over night and flush them.

    Believe me.. I know how to clone. No need to tell me what I do and dont know.

    YES I GROW IN HYDRO and I dont take pics of my grow except for my personal few plants where I have questions to ask
  13. You said you do "test studies" for Grodan.. they're the ones recommending this.. maybe you should communicate with them about this method.

  14. ok dont get mad bro..i even + rep'd ya the other day for giving your opinion in a polite manner but i disagree...were all entiltled to disagree bro..
    i'm not bagging you, i'm askin...cause it makes a huge difference..
    your nutes play such a particular role in a self building hydro setup it's unreal man..
    i have more nute lines (i test those for companies too) it's rediculous bro..
    there all different and from my experience changing nute formula's that creating a neutral ph work's you better control over the ph ...
    some nutes have ph buffer's some don't..some are sythetic/organic some are full sythetic..

    i understand what grodan say's on the bag..your right homie, it say's that shit...but grodan is about to be out of buisness watch...
    rockwool is loosing face value these day's..shit feel's like gooy fiberglass after running it one time..non reusable..get's fiber's in everything, pump's filter's etc..
    i hate the stuff to be
    i like the new sure to's made from a 20oz bottle of coke..
    but ph neutral and no rinse or anything required...r/o water is ph neutral so i use it in my rockwool overnight plug or cube does not matter..
    sqeeze it out and then use it..

    it will neutralize the ph this way..
    i never understood why rockwool companies suggest 5.5ph anyway...5.7-6.0 seem's better for nutrient uptake on every chart i've ever seen in 26 years..

  15. i have...they dont take mj into acount...but sure to grow does! lol they have med grower's all over using the stuff..
    they give those direction's because there reader's and scientist who never grew a pot plant in there life! lol
    most horticulture product's are endorsed by some guy with a degree in horticulture but never really owned his own nursery , greenhouse or grow op
    like a damn car salsesman...sell a car but can never fix
    i guess as long as people still buy it they don't care..
  16. Sorry I didnt mean to come off as angry, its hard to tell a tone in typed text. It wasnt my intention.

    You're right, everyone is allowed to disagree and in case I wasnt clear, I wasnt disagreeing with you in regards to adjusting the ph on the rockwools and Yes, I agree with you that there is much better media out there.

    My instructions were for the grodan (rockwool) starter plugs. The suggestion of 5.5 PH is not for nutrient uptake. The reason for the 5.5 ph is because its acidic and it dissolves the alkaline stone. For example, take an eggshell and leave it in vinegar which is acidic. Come back a couple hours later the eggshell will be gone.

    That 1 inch rockwool will hold the 5.5 water long after dipping it in... by the time that water evaporates it will take hours and during that time the alkaline stone will be dissolved.

  17. i understand bro, your following direction's correctly and doing what work's for you..i get's all good..
    i'm just a picky f'k lol
    and after doing my studies i cut grodan and other rockwool out of my grow's..
    now i get it for free and it i give it away to buddies! lol
    i just used the last 5-6 plug's i had for taking clones just to get rid of it..

    have you ever tried sure to grow?
    that shit rock's ass..
    any rate.
    your way is not wrong, i think we just do shit different but as long as it work's then it's fine..
    i don't spend cash were i don't need to, imho i feel that seedmat's are kinda a waste that's all..and i hate any fux in my ph, i like that rock steady from start to finish, so i make my rockwool drop your's...either way work's i just feel that neutral ph's are easier to work's the agree to disagree
    but i also don't buy expesive digital meter's either and nail my system's everytime with a regular gh kit..back in the day..there was no digital ph meter's or any of that stuff ya as thing's like this came on the scene over the years i was left asking why?
    it's all about getting you to spend money and product
  18. well here's my views....I have cloned with 100% success with Grodon cubes soaking the cubes in tap water just long enough to saturate, drain and become moist before adding the clone.
    I will admit I have never done this from a seedling, but would ph neutralize the cube first(especially for hydro)by soaking a few hours. I would also germ the seed first and put the tap root pointing down only to get the seed to sprout faster. A heating mat depends on temperature of the enviorment, but think is a good thing to do to keep the roots warm. A humidity dome is not an option, but a must for my success and only mist the cubes when needed to aquire a moist humid enviroment. This technique works well in soil grows, but with hydro is a little more of an exact science.

    I think all of the ways expressed in this thread will work, but one thing that intriges me custom2802 is why would the temperature using a heat mat encourage male plants. From what I know it is in the genes to be X-0 unless stress occurs and then possible hermies at best.

  19. it's just research..
    it's an on going study by many breeder's including myself.. and dutch passion released this article from there archives on stress, temp's nutes and the male to female ratio..
    i could'nt tell you exactly why to be honest..but i experimented with this about 6-7 years ago and it really does work..nute reg and certian level's of n-p-k can also effect the female offspring from regular seed as well..
    it's all about ideal or optimal condition's for a particular sex...
    females like certian temp's and certain nutes/condition's and males and/or hermies like it different ..

    here read this it's great info from dp

    "Courtesy of Dutch Passion" :D

    In November 1998 we introduced our "Female Cannabis Seed". We did this after our own experiments showed that from female seed, we acquired almost 100% female off-spring.

    In the meantime we are six months further on . We have received a lot of feed-back from our customers. The reactions are mostly positive, clients who have successfully produced almost 100% female off-spring. However there have been reactions from customers who found a few hermaphrodites or males plants. Apparently environmental influences affect the sex of the female seeds as well. Because of the fact that Female seeds do not grow into female plants under all circumstances, we changed the name from "Female Cannabis Seeds" into "Feminised Cannabis Seeds".

    From literature and from our own findings it appears that the growth of a male or a female plant from seed, except for the predisposition in the gender chromosomes, also depends on various environmental factors. Not only the origination of entirely male or female plants is partly affected by these environmental factors, the number of male and female flowers on a hermaphrodite plant is affected as well. The environmental factors that influence the sex of the plant (or the flower in the case of hermaphrodites), are among other things:

    The quantity of nitrogen and potassium of the seedbed.
    Humidity and moistness of the seedbed.
    Level of temperatures.
    Colour of the light used.
    Length of daylight.
    Stress, any form of stress, makes that more male individuals will originate from seed. Even the taking of cuttings from female plants may produce male or hermaphrodite cuttings.
    To optimise the result, changes in one or more of the above-mentioned environmental factors for a certain period during growth, may be applied. During this time these environmental factors will deviate from the standard growing system for maximum harvest and quality, as described in nursery literature. The desired change(s) in the environmental factor(s) are started from the moment that the seedling has three pairs of real leaves (not counting the seed-lobes). This is the moment that male and/or female predisposition in florescence is being formed. After approximately two weeks the standard growing system can be reconverted to.
    Of the 5 above-mentioned environmental factors the first three are the most practical:

    1. Level of nitrogen and potassium of the seedbed: A heightening of the standard level of nitrogen makes for more female plants originating from the seeds. A lowering of the nitrogen level shows more male plants. A heightening of the level of potassium tends to show more male plants, while a lowering of the potassium level shows more female plants. A combination of a higher nitrogen level for the period of a week or two and a lowering of the potassium level is recommended.
    2. Humidity and moistness of the seedbed: a higher humidity makes for an increase in the number of female plants from seed, a lowering for an increase in male plants. The same is valid for the moistness of the seedbed.
    3. Level of temperatures: lower temperatures make for a larger number of female plants, higher temperatures for more male plants.
    4. Colour of light: more blue light makes for female plants from seed, more red light makes for more male plants.
    5. Hours of daylight: few hours of daylight (e.g. 14 hours) makes for more female individuals, a long day (e.g. 18 hours) makes for more male plants. *

    Now let me just make a few adjustments here to this. You can do whatever you want to your plants in seedling stage and early vegetative stage of growth and it will not effect your final male to female ratios. The time when things should be near perfect is in or around the 3rd to 4th week of vegetative growth. This is the CRITICAL TIME for getting those female ratios up and up. I realized this clearly when noticing how some plants hermed because of problems that occurred around this period of the plants development. If the problems occurred before this time - no herms. So for this reason I surmised that this is when the crucial gender selection is made by the plant. Now I believe that the genders are set in the seed however the environment has a massive impact on how this is expressed in the final phenotypic expression of the plants gender. There are probably many genes that govern this, however lets get into how to up these female ratios.

    At the 3rd to 4th week of vegetative growth make sure that your plants are free from stress. No pests attacks, no fungi attacks, no mold, no irregular photoperiod, not underwatered, not overwatered, not pruned or topped, a cannabis friendly soil mix, not recently transplanted, no small pots. If have these basic growing conditions under control then we can move onto the real forces of female production from standard seeds.

    N:K and nutrients. What this simply boils down to is that you have the right nutrients present in the right ratios. A nutrient formulation that has roughly equal parts N, P and K is great but if the P levels go up or the N levels go down you are starting to look at a flowering type food for cannabis. If you do this then your odds of producing mostly females is greatly decreased. Make sure that you get those N, P and K levels to almost run from higher to lower amounts from N to P and K. I have noticed that equal portions of N to P an K can help with the female ratios but the higher N is certainly more helpful. So around the 3rd of 4th week of growth make sure that the ratios are good and that P or K has not gone above the N and P or else more males will occur. Obviously this means to avoid overfeeding your plants around this time too.

    Never let your medium dry out completely around the 3rd to 4th week of vegetative growth. If you make sure to water occasionally, but not to overwater your plants, you will get those female ratios on the up and up. Overwatering or drying out of the medium will only produce more males. For consistent results in getting more females keeps those mediums moist.

    Humidity. Now this is the tricky one. High humidity levels only promote fungi and mold development and lowering humidity levels is the way to cure most of this rot but by keeping those humidity levels up in or around the 70 rH factor will help to produce more females. If you have a low humidity grow room then you should get to hold of a humidifier. Now high humidity levels like 70rH cause the medium to dry out a lot quicker so you got to keep this under control too. Keep those mediums moist and those rH levesl at 70. This will help to improve those female to male ratios. Again, getting them on the up and up.

    If you run the 24/0 photoperiod then do not allow those temps to go anywhere above 85 unless you have an equatorial strain. 75 is the best but going a little lower is not a problem for helping those female ratios. If you can get in at around 65 then those females are going to be popping up all over the place. The problem with this is that some growers like to use the 18/6 photoperiod and when the lights are off the temps drop from around 65 to 50 and even less. Try not to be below 55 because this has the adverse effect on the plants producing more males than females. Again between 65 and 75 is where you want to be during the 3rd to 4th week of vegetative growth, the preference being 70.

    Invest in a MH Light for vegetative growth. Dump the HPS bulb for flowering later. I have noticed that HPS lighting during vegetative growth simply sends those males to female ratios all over the place. With MH lamps the females are everywhere. Invest in some MH HID lights. It makes all the difference in getting those females to show more often. This is worth repeating! MH Bulbs produce more females under optimal conditions especially if they are present during the 3rd and 4th week of vegetative growth. Surprising enough you can start seedlings under HPS and it will not have an effect on those female ratios. Again the 3rd to 4th week of vegetative growth is what is important here.

    No stress during the 3rd to 4th week of vegetative growth. That is all there is to it. If you got your garden growing in optimal conditions without plant stress then the impressive 90% to 95% females start to emerge from standard seed packs. I find that topping is best done at the second to third week of vegetative growth but that this is a little stressful and can lead to those female ratios dropping again. Avoid topping or pruning if you are looking to up the female count.

    That is all I have to say for the moment. These little snippets of information in conjunction with what DP uncovered have helped my female ratios considerably. Hopefully you can see the same results too. Have fun getting those environments optimal for females!!!!!!!!
  20. Very interesting and informative read...:cool:

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