Lucas Formula

Discussion in 'Growing Marijuana Indoors' started by James, Mar 1, 2009.

  1. #1 James, Mar 1, 2009
    Last edited by a moderator: Mar 1, 2009
    Hi Guys,:wave:

    New here to GC.. I was cruising the posts and tried to find some info about the Lucas Formula. I found this link I have a question about the M-B-G. I know that these stand for Micro, Bloom, Grow; however are these references to a customized mixture of nutes to be given at each phase ie, Bloom, Grow, etc.? And if they are, is there someone that can esplain this a little bit more clearly for me?

    Thanks Much!

    BTW, I'm currently using SuperThrive Hormones, Rooting Formula, and Shultz plant food (10-15-10). The clones have already rooted, they are about three weeks old and all averaging 7inches with about 4-5 solid leaves and 6-7 nodes(as of today), and have already been pre-flowering for about a week and half. Im using a 1000w MH 24in above plant tops at 18/6, with ventilation, my soil temp is 73deg, and air humidity is 64%. My pH is maintained every time i water at 6.5, in a aggregate4 mix. Can anyone let me know what i can do better, if not already done? Thanks again....
  2. Here try this:

    Here try this:
    General Hydroponics Flora Series Feeding Strategy - Lucas Formula

    G-M-B (Grow-Micro-Bloom)
    0-5-10 - For Vegetative cycle (24/0)
    0-8-16 - For Flowering cycle (12/12)

    The numbers above indicate the number of milliliters (ml/cc) of Flora Grow, Flora Micro or Flora Bloom formulas that I use in one gallon (US Liquid) of nutrients.

    You will notice I dont use any of the "Flora Grow” formula, do not need to, the "Flora Micro" provides plenty of Nitrogen.

    1. Top off the reservoir daily using a pH corrected water solution as required to maintain full reservoir level. After adding back an amount of water equal to the amount of your reservoir capacity you should change the reservoir and put in fresh solution.

    How to use the Lucase formula in my bucket?
    I will give an example step by step.

    Vegetative cycle (first stage of growth when the lights are on 24 hours a day):

    My bucket's fill point is at 3.5 gallons. So I need to measure 3.5 gallons of pure water (distilled or reverse osmosis) into an empty bucket (not your bubble bucket, just a clean bucket).
    The formula calls for 5cc of Flora Micro per gallon (5x3.5=17.5cc). So I add 17.5cc of the Micro to my bucket of water. Stirr it in good.
    Next the formula calls for 10cc of Flora Bloom per gallon (10x3.5=35cc). So I add 35cc of bloom and stirr.
    Always add the nutrients seperate. Never mix them together before stirring them into the water.

    PH....... Your PH needs to be between 5.7 and 6.2. Test your nutrient. Add your adjustment solution in small amounts until you know how strong the stuff is. Mine take 5 full eye droppers of PH up to get my target PH of 6.0
    Yours will not be the same. Depends on the water.

    Flowering Cycle (lights on for 12 hours and off for 12 hours).

    Same as above except a bit more nutrient.
    8cc of micro per gallon (8x3.5=28cc).
    16cc of Bloom per gallon (16x3.5=56cc) .
  3. Hey Rumple,

    Thanks for that info. For some reason it didn't really click, unitl you replied and I found that it was a "brand" of Nutes and their startegy...haha. So anyways, I will be picking up some of that stuff from my local store that carries it, and will be posting pics soon...

    Will changing the nutients stress the plants any? Does the SuperThrive Hormones really make a difference to add or remove it to the formula?

  4. I would not add a damn thing to the Lucas formula, no matter how cool the name or picture on the bottle is.

    The plant will always do better being under fed, then over fed. Don't add any crap to your nutrients if you have a balanced mixture.

    It is our nature to want to give a boost to our plants. This is something we need to keep in check.
  5. I couldn't say it better.

    The only thing I've changed over the years with the Lucas formula is I've switched to General Hydroponics' FloraNOVA series. Lucas himself switched to the FloraNova line of nutes a few years ago.

    The 'Bloom' formula is supposedly the Lucas formula with a professional mix of additives. I definitely see a remarkable improvement over the 3-part series. I use it at exactly 8ml/gal of RO water like Lucas recommends.

    The 'Grow' formula is an excellent vegging formula.

    Both are super simple.

    There is plenty of Cal/Mag and other stuff in both the Lucas formula using 3-part and the FloraNova series. NO ADDITIVES ARE NECESSARY.

    If you're seeing deficiencies around day 20-30 in flower, up your pH to around 6.0-6.2 for a week or two and you'll see that go away.

    There is NO NEED for adding Cal/Mag or Epsom Salts. This only makes your life more difficult. :)
  6. couldn't find where but i've read that at some point in flowering you should start decreasing the ppm of the flower formula. anybody know at what point that is or if that's even correct?
  7. I'm sorry (maybe retarded.)

    All I need from start to finish is flora micro and flora grow? You dont use any of the zillion other flashy and expensive nutes or additives. None?

    Sorry to appear so stupid, but I had to ask:eek:.
    Thank you.
  8. P.S. Ill be doing a hydro grow with General Hydroponics Waterfarms if that makes any difference. I keep thinking it can't be this simple, but then again I am a Nube.
  9. It really is that simple..........check out Rump's harvest pics in his sig.........hes been a proponent of the Lucas formula for quite some time. You can use the Advanced Nutrients Micro-Bloom......but why mess with success and pay more money.
    It's real easy to get caught up on the nutrient bandwagon with all the boosters and additives and accelerators and on and on and on.........keep it simple.....Lucas.
  10. #11 nu-bube, Sep 24, 2009
    Last edited by a moderator: Sep 24, 2009
    You are right . Amazing pics, the man is a god! And thanks for answering my question.

  11. At least 14 days. It's very important to leach the excess nutrients out of your plants before you harvest. You shouldn't have nice green fan leaves at harvest day.
  12. High foreskin... good stuff

    I believe that the Lucas formula is:

    0-5-10 : For low light growing (florecents, etc..


    0-8-16 : is for HID light growing

    There is no Lucas 'vegative' formula... start to finish 0-8-16 (HID) or 0-5-10 (low ligh applications

    No need for flushing, if addbacks are kept at initial PPM levels (eg, 0-8-16 in on gallon of RO = 954PPMs.. @ a EC conversin of .5.
    (although I use 0-8.5-17, preventing minor mg deficiency.. in MY grows)..

    according to Lucas, and my practice, no res changes or flushing are necessary.. taste is very good and strain specific, and yields have been very good... cost $$$ of nutes way down = GREAT!

    I re-read that CW thread a couple times a year and reference it almost every time I have a problem...

    It is a simple and 'labor lacking', low cost growing methodoligy..
    Lucas prefers clay balls and E&F.. I use it in DWC...

    Here is a GH calculator that might be useful to some.

  13. I know this is an old thread but interesting.

    I would like to avoid dumping the res if I don't have to. How do you keep the nutes at the proper level when if is an 80 gallon res?
    What PPM would I want to stay at during veg?

    Also, what would you suggest on the first 2-3 weeks of startup while cuttings are small?
  14. Good luck getting an answer on that one. Apparently no one here knows.
  15. At some point Your ganna hafta to dump ur res and start with new solution.Just continually adding water and nutes ull end up with a disaster.Regardless get rid of the shultz's and get a 1-2-3 part set of nutes and stick with them till you figure out works best .I take it your growing in soilless medium,When I first started indoor I used Age Old Organics G-B-Kelp and it was simple and worked great.Also If your gonna change nutes in the middle of a grow I would flush em good.As far as additives they work but I'd say get used to whatever nutes u pic first before u start adding extra additives

  16. I top off with 1/2 strength every other topping off and it works for me. For the initital 2-3 weeks I use plain water with no nutes and it works fine too. :smoke:
  17. Finally. Rep to you.

  18. LoL thanks man!

    Wanted to point out the alternate every other toppings are at full strength.

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