lucas formula
- Thread starter iboga
- Start date
While it's not exact, 4 liters per gallon is close enough for our purposes.
Am I correct in assuming that I can use just about anything so long as the NPK ratios match up with the NPK ratio of the lucas formula or is there more to it than meets the eye? I've also read a few things about nitrogen deficiency when it comes to the lucas formula. Any comments on that?
I know each strain has a sweet spot and the lucas is sort of a starting point that will generally work for all strains but I'm just asking for verification on a few things.
I know each strain has a sweet spot and the lucas is sort of a starting point that will generally work for all strains but I'm just asking for verification on a few things.
txskunk, the lucas formula is rather outdated as it was developed before the advent of tissue analysis. newer research is showing that a 3-1-4 ratio is probably better.
i used the lucas formula for years and it works fine but i feel it is a little light on nitrogen as you said.
one thing i noticed was that my strain on the lucas formula did not develop hollow stems in veg.
once i switched to the 3-1-4 ratio using jack's hydroponic special and calcium nitrate i got hollow stems, bigger plants in the same time frame and a higher yield. lucas himself remarked on the hollow stem observation when he ran a higher nitrogen version in veg by using gh's product. he said he got the biggest yield with it.
i used the lucas formula for years and it works fine but i feel it is a little light on nitrogen as you said.
one thing i noticed was that my strain on the lucas formula did not develop hollow stems in veg.
once i switched to the 3-1-4 ratio using jack's hydroponic special and calcium nitrate i got hollow stems, bigger plants in the same time frame and a higher yield. lucas himself remarked on the hollow stem observation when he ran a higher nitrogen version in veg by using gh's product. he said he got the biggest yield with it.
The only deficiencies I've had were all caused by improper pH.
Please, Sir, may we have more? Is that veg or flower? Inquiring minds and all that....
Please, Sir, may we have more? Is that veg or flower? Inquiring minds and all that....
hi, i never said anything about deficiencies. i didn't get any spotting or anything visual and it actually works pretty good.
it's simply that i get much better growth with the jack's and calcinit.
i run it at 600 ppm at the .5 conversion in both veg and flower.
btw, when used with ro water no ph adjusters are necessary. i really don't monitor ph anymore, but i recently checked a plant reservoir after whacking a plant and got ph 6.0 and i think 778 tds or something like that after 9 weeks of 600 ppm with no change outs.
i hope this helps those inquiring minds. d9
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IwannatokeNbone
Member
lucas formula isnt that special i agree, i still have some of the micro series stuff, it never impressed me, floranova bloom did though, in comparison my fnb plants had much more shine n health then 6/9 ever gave them.
Do you have any links to read up on this?
Or if this is from your own studies, give us more.......
petemoss
Active member
Well this is a long and detailed thread discussing the Lucas ratio written by fatman: http://www.rollitup.org/hydroponics-aeroponics/268790-lucas-formula-recipe-scratch-really.html
I've used the Lucas formula with GH Flora 0-8-16 as well as Floranova bloom, which is GH's one-part Lucas feed. It worked well, but I've since found a better (and cheaper) feed thanks to delta9nxs : Jack's hydroponic plus calcium nitrate.
hi, the 6/9 is the rez/head adaptation of the "lucas" formula and is intended for coco only. works good but you can take the flora nova bloom at 6 ml per gallon which should give you around 750 ppm at .5, add 100 ppm calcium nitrate and 50 ppm magnesium sulfate and bang it in coco. no visual displays of the cation exchange issue that most report in coco the first 2 weeks. this works great in hand watered coco.
the jack's works right out of the box if you pre treat the coco with a 2000 ppm pour through before transplant. i used 600-750 ppm after that in coco.
hi, this comes from reading and my own experience. i'm digging out some links and will put them up later.
meanwhile i'll leave you with something to think about.
from lucas on the “ask lucas” thread at cw.com
"now lets talk about vegging
if newly rooted clones are transplanted into containers that are going to veg under fluoros, that is a sort of weak light situation, and using weak nutes makes sense, ~1000 ppm
but after the first week or two of fluoros, if the plants move to strong light, HPS light, or MH light, but with big lamps, you know, not fluoros, what is referred to as HID lighting.. then I want them to see full strength nutes.. 0-8-16.. ~13-1400ppm
now to the question of vegetative formulas
I find the use of FloraNovaGrow definitely kicks the vegging plants into greener, but also stretchier gear. In fact, vegging with FNGrow, the stalks turn into big hollow things that look like celery.. whereas when vegging with FNBloom, as I have always advocated in the past, vegging with bloom nutes, produces much more solid stems
sidenote, Clarke claims there is some belief that drug cultivars have hollow stems. I dont know if this is true, but I do know that higher doses of Nitrogen than the bloom recipe I know so well, produces hollow stems in plants that did not have them before..
anyway, back to the veg nute thang
I think vegging in FloraNovaGrow instead of FNBloom has some positive effects on kick starting the plants, so I devised an experiment..
a bubbler reservoir was mixed with FNGrow, and plants were vegged in it for a week, then, instead of dumping, when the light was flipped, all nute additions were FloraNovaBloom from then on.
so in this case the grow nutes stayed in the res, after veg ended, but only bloom nutes were added to the res when addbacks were made
this totally unreplicated experiment produced one of the highest yields that gardener has reported.. 1.75lbs per 1k... nothing outrageous, but, the cola size was huge!.. twice as fat as usually seen when veg is done with a low Nitrogen, bloom style nute
what Im driving at is the idea of feeding the stretch that Mr. Highway mentioned in the past.. the idea of nitrogen loading the initial days of 12/12.. I think he was on to something..
point of the story, even in this scenario, a res with Grow nutes during veg, not just weak bloom nutes, was not dumped, the Bloom nutes were simply added to the res as the bloom cycle went along consuming TDS..
so to your original, and insightful question, can one simply keep adding bloom nutes to a vegetative res, once the light is flipped, without dumping the veg res,,, my opinion is YES!"
this is what i was referring to when i mentioned hollow stems as a mark for nitrogen. my own experience with this shows a marked increase in yield when the feed produces hollow stems in veg. i believe hollow stems aid plant hydraulics.
neither 8/16 with the flora series or 8 ml per gallon with fnb produces hollow stems.
hey, pete! good to hear from you and thanks for the help! i was going to link that one but you saved me the trouble. come over to my place and talk about shit sometime.
later on
here is another interesting article. while not alluding specifically to the lucas formula he does mention the use of 2 parts of a 3 part formula at a 2/1 ratio so it is obvious that's what he is talking about.
http://maximumyield.com/article_sh_db.php?articleID=464&yearVar=2009&issueVar=August
the article also points to the futility of using p-k type bloom boosters.
http://maximumyield.com/article_sh_db.php?articleID=464&yearVar=2009&issueVar=August
the article also points to the futility of using p-k type bloom boosters.
The 3-1-4 'ratio' (really it's a form of relativity) is what I and others (like tester, YosemiteSam, Analog, Avenger, etc.) have developed (together and separately) using cannabis tissue assays and tissue assays from other higher green C3 plants.
I have been testing and using 3-1-4 for a long time, and it works exceptionally well from veg to harvest for coco, peat, water culture, etc. The low (yet sufficient) P is a key factor, esp. for veg and pre-flowering, as is the increased N. At this time, my mixes are the only ones using ~3-1-4, that I am aware of; I know YS likes to use lots of various relativity to see what he likes.
There are at least a dozen people testing my General Hydroponics mix meant to replace the PH/Lucas formula and Rez formula, as well as my formula(s) using base salt compounds. So far, at least a half a dozen people have tested my GH mix, and found it's far better than other mixes (from GH and otherwise) they have used before. I think that's because my mixes are based on science ...
In terms of K-Ca-Mg, I have found (as have others) that 3-2-1 works very well.
FWIW, I would put my mixes against any commercial brand there is; and I would bet as much money as I have, that my mixes will beat the shit out of any commercial mix.
To find N-P-K (what I term N|P|K) and K-Ca-Mg (what I term K|Ca|Mg), the following math is used:
If:
And:
Then:
I have been testing and using 3-1-4 for a long time, and it works exceptionally well from veg to harvest for coco, peat, water culture, etc. The low (yet sufficient) P is a key factor, esp. for veg and pre-flowering, as is the increased N. At this time, my mixes are the only ones using ~3-1-4, that I am aware of; I know YS likes to use lots of various relativity to see what he likes.
There are at least a dozen people testing my General Hydroponics mix meant to replace the PH/Lucas formula and Rez formula, as well as my formula(s) using base salt compounds. So far, at least a half a dozen people have tested my GH mix, and found it's far better than other mixes (from GH and otherwise) they have used before. I think that's because my mixes are based on science ...
In terms of K-Ca-Mg, I have found (as have others) that 3-2-1 works very well.
FWIW, I would put my mixes against any commercial brand there is; and I would bet as much money as I have, that my mixes will beat the shit out of any commercial mix.
To find N-P-K (what I term N|P|K) and K-Ca-Mg (what I term K|Ca|Mg), the following math is used:
If:
- N = total ppm of ammonicial and nitrate
- P = total ppm of P
- K = total ppm of K
- L = represents element with lowest ppm
And:
- N = 150
- P = 50
- K =200
- L = 50
Then:
- N/L = 3
- P/L = 1
- K/L = 4
hey! 3-1-4, the golden ratio, beginning to end. your formula looks good. have you looked at the jack's hydro special and calcinit combo? it comes out to 150-52-215. i'm growing very nice plants with it but i will try your formula sometime. have you got those tissue assays up somewhere? i'm sure they are better than the AN ones i was going to link.
Hey buddy
I agree it's interesting, but Erik is wrong on a few points. And he appears to lack critical depth of understanding, at least his article lacked said depth. Ex., he makes claims as fact, which are not fact, such as:
Also, the following claim is totally wrong. The last thing a grower wants to do is spike P before the stretch in per-flowering is over. That is, unless the grower wants longer internodal lengths and a plant that stretches quite a bit more than when using lower P. Also, the claim that bloom boosters, a'la Big Bud (et al.) "have other components in the formulation that help to control vertical growth" is hogwash; unless Erik would be so kind as to state the "components" to which he is referring in a very unsubstantiated manner:
I agree it's interesting, but Erik is wrong on a few points. And he appears to lack critical depth of understanding, at least his article lacked said depth. Ex., he makes claims as fact, which are not fact, such as:
"In the late flowering phase, when the plant is ripening, and in some instances producing elevated levels of essential oils, a slight “spike” in phosphorous levels will induce a level of stress that can help to enhance crop quality."
I would challenge him to prove those claims with legit scientific data, on cannabis. I'm not claiming he's wrong, but I am calming he can't make such a factual statement without references and proof, of which he provides none. IMO he is simply using hearsay and the logical fallacy "argument from common belief", etc.
Also, the following claim is totally wrong. The last thing a grower wants to do is spike P before the stretch in per-flowering is over. That is, unless the grower wants longer internodal lengths and a plant that stretches quite a bit more than when using lower P. Also, the claim that bloom boosters, a'la Big Bud (et al.) "have other components in the formulation that help to control vertical growth" is hogwash; unless Erik would be so kind as to state the "components" to which he is referring in a very unsubstantiated manner:
"For the first week of flowering to help trigger the natural plant stresses that amplify the plant’s flowering process, it’s okay to give the crop a dose of bloom boosters that have higher P to K ratios in the NPK values stated on the label. Usually, these types of bloom boosters that are formulated for indoor crops at the onset of flowering will also have other components in the formulation that help to control vertical growth; stacking internodes and flowering sites tighter together for each foot of vertical growth to give maximum yields."
Besides those points, a few others, I agree with the thrust of Erick's article.
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No, but I have made something better IMO (see below), using Peter's Hydro-Sol, Calcinit, etc. I'm testing the following mix starting this month, the ppm values are well proven in lots of my previous testing. There are about 6 other people that will be testing my ppm values, including thefatman.
Direct addition to 100 liters in reservoir (no stock solutions):
(not shown below is boric acid at 0.095 grams)
Stock solutions, per gallon for mix A, B and C (not direct addition to reservoir); used at 10 mL per liter, for A, B and C:
(not shown below is boric acid at 0.361 grams into mix B)
Here is a thread worth checking out, my posts with respect to this post start on page 9 or so. In my posts I provide many links to great lit on these topics, as well as my mixes, info on how to properly mix fertigation water (ex., add ferts to 1/2 volume of total water, then add other 1/2 volume of water), etc.:I.) Notes:
...
5) After messing around with lots of mixes, I found the perfect mix of inexpensive salts. The mix provides N-P-K of 3-1-4 and K-Ca-Mg of 3.2-1.84-1; as well as providing sufficient Si, NO3:NH4 ratio of 14, etc. Using the following salts, excluding the micro's, increases the accuracy of the ppm calculations. Using all of the following salts I was able to reduce the price per unit, too:
...
--> I attached two screen shots, the first one, "complete_mix_a", shows how to make the stock solutions (mixes) A, B and C. Ex., how much of each compound to add to each gallon to make stock solution (not shown is 0.361 grams of boric acid into mix B). That screen shot also shows the elemental profile by ppm, providing exactly what you asked for. The EC shown is 1.6 mS/cm, which is the EC of the fertagation water after the specified volumes of mix A, B and C are added. If we include the EC of your source water, i.e., 0.4 mS/cm, the total EC for your fertigtion tank will be 2.0 mS/cm; and I believe that is the EC you requested, correct?
II.) Mixing notes for stock solution:
a) when weighing dry salts use two scales: one that measures down to 0.001 gram and is accurate to 0.001 gram (jewelry scale for micro-nutrients), and one that measures to 1 kilogram and accurate to 0.01 gram, better yet 0.001 gram. Following is an example of en Ebay search for 0.001 gram scales: http://shop.ebay.com/items/?_nkw=sc...pt=1&_sadis=&LH_CAds=&clk_rvr_id=248929254212
b) when measuring liquid volume, ex., for Silo-Tec potassium silicate, use a good graduated cylinder, and a syringe for single mL and less than mL measurements. However, we can find the specific gravity of Silo-Tec and then use weight, instead of volume, to measure out Silo-Tec for mix C.
c) fill jug for mix A with 1/2 gallon distilled or deionized water, then add the salt compounds for mix A, shake and dissolve with each addition. Then add the other 1/2 gallon distilled or deionized water and shake.
d) do the same as above (re: mix A), when mixing B, and C.
III.) Mixing notes for fertigation tank (working solution):
a) fill tank to 1/2 volume with source water needed, ex., if you need 100 liter, fill with 50 liter.
b) add mix C (potassium silicate) at 10 mL per liter of total tank water and mix/agitate to fully dissolve (wait a couple of minutes), then adjust pH.
c) add mix A at 10 mL per liter of total tank water and mix/agitate to fully dissolve (wait a couple of minutes).
d) add mix B at 10 mL per liter of total tank water and mix/agitate to fully dissolve (wait a couple of minutes).
e) adjust pH
DIY Nutrients formulations, recipes, chemistry etc.
https://www.icmag.com/ic/showthread.php?t=199034
https://www.icmag.com/ic/showthread.php?t=199034
Here ya go, esp. see the last two pages. A buddy of mine will be doing at least 100 assays in the coming month/s. And my next grow I will be sending in petiole samples once a week for assay.
Hemp (Cannabis sativa L) tissue nutrient analysis data
https://www.icmag.com/ic/showthread.php?t=181405
https://www.icmag.com/ic/showthread.php?t=181405
Spurr,
What are the GMB volumes per gallon to get the 3-1-4 ratio?
Edit. You posted before I got mine in. I thought you were using GH 3 part to get there.
What are the GMB volumes per gallon to get the 3-1-4 ratio?
Edit. You posted before I got mine in. I thought you were using GH 3 part to get there.
