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420NLGuy
08-31-2009, 10:01 PM
I have two Northern Lights plants that were growing great until Week 6 (Day 42 or so), when I noticed that #2 was wilting. By the end of the day, it had really gotten worse. They were in 6" pots. So I suspected it might be root-bound, so transplanted #2 to an 11" pot. It started showing life again 7 days later. But the buds are really small. They are about the size of a cigarette filter.

Now #1 is dying. At first, I thought it might be a Magnesium deficiency (after reading online about that). So I fed both plants with Epsom Salts and started foliar-spraying with Epsom Salts as well. #2 is looking better, but #1continues to die.

So I finally transplanted #1 to an 11" pot yesterday. But I don't know if it's too late to save it.

Here are some pics.

#1 at Week 7: Transplanted from 6" to 11" pot on 8/30/2009
[attachment=o226442]

#2 at Week 7: Transplanted from 6" to 11" pot on 8/21/2009
[attachment=o226443]

Anyone have an idea of what the problem is? Is it a rooting problem due to a too-small pot? Is it a Magnesium deficiency?

Specs
Light: 24W 6400K CFLs for veg, 26W 5000K CFLs for flower, 2" from plants [for 3000 lumens/sq. ft.]
Soil: Tierra Negra (Spanish for Black Earth -- I'm in Panama]
Nutes: MG All-Purpose diluted to 50% recommended strength
Seeds: Northern Lights
Days in Veg: 57
Days in Flower: 52 [as of 8/31/2009]

ForgetClassC
09-01-2009, 03:48 AM
Why are you growing in mud? Cannabis doesn't grow in swamps for a reason........

-C

killerweed420
09-01-2009, 07:16 PM
The bigger pots may not help now if they were root bound. I prefer to move my clones from cups directly to 3 gallon pots. They also appear to be overwatered.

bractdoctor
09-01-2009, 11:13 PM
Those plants have had a bad life. You need to get a grow book,and read it before you attempt to grow again. Too much water, over ferted, not enough lumens, the whole nine yards. Good luck BDrx

headshake
09-02-2009, 12:15 AM
you also might get better answers to your questions if you post in the correct sub-forum. try plant problems (http://boards.cannabis.com/plant-problems/) next time. basic growing is what you should be reading!

read the stickies in all of the basic growing forums and try again!


-shake

themasta09
09-02-2009, 11:59 AM
Wow im a FTG myself and i cant beleive how your plants look, I was gonna say if your 6 weeks into flower and they are bad then just stick em in darkness for 48 houirs and then harvest,
but to be honest looking at them its not worth doing.

The only thing i would suggest is maybe trim them back a bit (taking off the worse) and stick them under 24 hour cfl light for 4 weeks to try and reveg them.

If moneys short just get some 'multi purpose compost' (anout 1.00gbp-$2 a bag)
some 7/7/7 npk ferts (for after a couple of weeks, and some nice pure bottled water (look on label aim for 6.2ph)

(the picture shows mine vegged under 24/7 3 weeks from clone (now in flower 2 weeks), in the said multi purpose compost, used npk 7/7/7 at veg and 'aqua pura' water, and nothing else--so although not ideal method it does work 100%, you just gotta have love for you plant for it thrive)

I mean thats the only thing you can do..
Good luck

Rusty Trichome
09-02-2009, 01:06 PM
Just a quick note...Miracle Grow All Purpose is good for vegetative growth, but unacceptable for flowering. You are going to want to look for something low in nitrogen, but avoid rose food unless absolutely necessary.

420NLGuy
09-02-2009, 11:49 PM
Thanks for the info.
To killerweed420, themasta09, and Rustry Trichome: thanks for your advice. I appreciate it.

To headshake: I did not know about that forum. I will post there from now on.

To bractdoctor: They did not have a bad life. Only recently did they develop this problem. See photos to follow. [And I did extensive research and planning first. Maybe you think otherwise because I only posted the problem shots.] So no need to get snippy.

I'm sure you all think this is how it looked from day 1. But those photos were AFTER they developed a problem. They were just fine shortly before that.

Here they are at 27 days into flowering:
[attachment=o226569]

Here they are at 36 days into flowering:
[attachment=o226570]

PS: To ForgetClassC: What do you expect to get from being so sarcastic? Respect? Thanks?

ForgetClassC
09-03-2009, 03:21 AM
Response.

-C

sunbiz1
09-03-2009, 03:27 AM
And?, is there anything you can use to promote more pistils and resin in flowering stages?

What's the proper 3 part nutrient mix?, and do you leaf or root feed??

Or perhaps just let nature take it's course???


Just a quick note...Miracle Grow All Purpose is good for vegetative growth, but unacceptable for flowering. You are going to want to look for something low in nitrogen, but avoid rose food unless absolutely necessary.

NeverEnough
09-03-2009, 11:02 AM
420NLGuy i know you said your using 26 watt cfl. How many do you have for the 2 plants?

you really should have at least 6000 lumens for one plant

headshake
09-03-2009, 03:29 PM
420NLguy, the plants didn't look bad before actually. you still need more light though. a lot more light! they are very spindly and thin. this is a prime indication that they aren't getting enough light. what happens is the plants cells grow faster when looking for the light. phototropism is when the plants grow towards the light. the cells in the shade grow faster causing the plant to bend towards the light source. this is basically what your plants are doing, but constantly all over.

any buds they made that were worthwhile would cause the tops to be too heavy and they would fall over.

no one is knocking your for trying to gain experience. it's just that there is a minimum recipie for success so to speak. if people weren't telling you how to improve your grow or offer advice then they would be doing you a disservice. not to mention there would be no need for the forums. sure sometimes (our) tact isn't perfect, but if you let that get under your skin then you should just go ahead and uplugg that ethernet cable in the back of your computer now!!! think about it, we get the same flipping questions hundreds of times a week. people don't introduce themselves, don't get aquainted with the rules, learn where to post or whatnot. they just want to rape the forums for answers and then burn off. kinda like veruca salt, you know from the willy wonka/charlie and the chocolate factory movies? "i want it and i want it now!" shit get's old. then you give advice and people want to debate you or talk trash to you from behind a keyboard. so, be like a duck be calm above the surface, but paddling like hell underneath and let the water roll off your back!

peace!


-shake

Rusty Trichome
09-03-2009, 03:58 PM
Why are you growing in mud? Cannabis doesn't grow in swamps for a reason........-C

To ForgetClassC: What do you expect to get from being so sarcastic? Respect? Thanks?
Actually, ForgetClassC was giving you another big clue to your problems. That crap you use is a top dressing, not a potting soil. Do you at least have perlite and lime (or some other ph buffer) in the mix, or are you just suffocating the roots and not worried about ph?

If your location limits your access to potting soil, I'd recommend you google the remedy (necessary ammendments to make it a potted-plant friendly medium) online, or see if you can access the individual components of potting soil, and mix your own.

Top dressings, most composts, worm castings...are all unacceptable as stand-alone mediums. They all hold water and make a muddy mess that suffocates roots, causes root rot, blocks nutrient uptake, and stunts all growth. (at the very least)

420NLGuy
09-03-2009, 05:24 PM
NeverEnough: During veg, I used one 24W CFL per plant. Each bulb is rated as 1560 lumens at 6500K. To get 3000 lumens/sq. ft, I calculated the distance to be about 2.5". Every forum I found had recommended to use about 30,000 lumens/sq. meter (which is 3000 lumens/sq. ft).

I used one 26W CFL per plant in flowering. Each bulb is rated at 1650 lumens at 5000K. So that also calculates to about 2.5" distance to get 3000 lumens/sq. ft. When the plants got tall enough, I used 2 bulbs/plant, giving them 6000 lumens/sq. ft.

But you say it should be 6000 lumens all the way? That is much more than others have recommended. Can you point me to a source on this?

headshake: The reason they look like they are bending towards the light source is because I used LST.

Rusty Trichome: Yes, I am very limited in what I can get. I am in Panama. I can't find Perlite, limestone, Fox Farms, or anything like that. The stores carry only MG stuff (soil, nutes). But I'll do some research to try to find amendments to make better potted soil.

But I really suspect that my problem was not repotting to a larger pot soon enough. The 1st plant I repotted 2 weeks ago came back to life. The other one died because I repotted it way too late (1 week ago).

headshake
09-03-2009, 11:00 PM
if you want proof that you need more light just read through some other CFL grow logs and compare plants, results etc.

here is some pictures of the ladies i have in flowering at the moment. can't remember how long i vegged em for exaclty. three weeks to a month i think. i also LST'd them. (and topped.) they were vegged under 6 x 23W, 1700 lumen, 6500K CFLs.

they'll be flowerd under 16 x 23W, 1700 lumen, 2700K CFLs. if you are still around i will share the results.

i'm not quite sure how you calculate a 1500 lumen bulb at 2" away doubles the lumens. i'm also not sure which forums you've been browsing where people tell you to use this method or that one CFL for veg and two for flower are sufficient. stick around here long enough and you might just learn something.


-shake

420NLGuy
09-04-2009, 12:39 AM
<> ... they were vegged under 6 x 23W, 1700 lumen, 6500K CFLs. they'll be flowerd under 16 x 23W, 1700 lumen, 2700K CFLs. if you are still around i will share the results. >>

What distance do you use from bulbs to plants?

<<i'm not quite sure how you calculate a 1500 lumen bulb at 2" away doubles the lumens. i'm also not sure which forums you've been browsing where people tell you to use this method or that one CFL for veg and two for flower are sufficient. stick around here long enough and you might just learn something.>>

The light intensity is a function of the square of the distance, just like gravity. So if you cut the distance by 2, you increase the intensity by 4 (2 squared).

Because this forum's text attributes don't provide for subscript and superscript characters, I can't show the formula that expresses lumens/sq. ft. with distance using just text. So I have to show it as a graphic:

[attachment=o226671]

So if you want 2800 lumens/sq. ft from a 1560 lumen bulb, it needs to be 2.6" from plant.

Note that 30,000 lumens/sq. meter converts to 2800 lumens/sq. ft. Also note that the lumen rating on all bulbs assumes a distance of 12" from object.

bractdoctor
09-04-2009, 01:28 AM
Not meaning to sound snippy my brother! I want everyone to succeed in every grow as I tell my students daily.... read all that you can.

You cannot get more lumens from a bulb than it is rated. That is a mistake. Most peeps I know who are using cflo's to run have switched to the largest they could find, and then, they use 4 of them for two plants. For a NL to stretch like that, being a mostly indica dominant plant it is telling you that there is no where near enough lumens there for it to flourish. Have you thought about buying one or two of the outdoor flood lights in HPS or MH? They come in 70 and 100 watts, and if you build a simple cabinet, you can successfully have enough lumens to run a successful, small show. One cabinet built by one of my students is 32" square x 46" tall, and has a 100 watt MH up top, and two of the 70 watt hps 's opposite another. This keeps the lumens above reccomended, and keeps the internodes tight. Again, sorry if I sounded "snippy", I am an old organic mechanic who has been doing this and teaching for many years now. I sometimes come across as an old coot!



Good luck! BDrx

bractdoctor
09-04-2009, 01:30 AM
Hey, try a couple of other websites for more help. UDG or unleashdagreen, and ICMag. Good luck!

ForgetClassC
09-04-2009, 03:18 AM
NeverEnough: During veg, I used one 24W CFL per plant. Each bulb is rated as 1560 lumens at 6500K. To get 3000 lumens/sq. ft, I calculated the distance to be about 2.5". Every forum I found had recommended to use about 30,000 lumens/sq. meter (which is 3000 lumens/sq. ft).

I used one 26W CFL per plant in flowering. Each bulb is rated at 1650 lumens at 5000K. So that also calculates to about 2.5" distance to get 3000 lumens/sq. ft. When the plants got tall enough, I used 2 bulbs/plant, giving them 6000 lumens/sq. ft.

The bold parts are where I have no idea where you get any of the calculations or distance equations. Light dissipates the farther you are from the source, whats this multiplication of foot candles 100% per inch?

Give me a source, and I'll still probably say that it's wrong, but I'm just ponderous of where you got those numbers......


-C

420NLGuy
09-04-2009, 04:09 AM
... You cannot get more lumens from a bulb than it is rated. That is a mistake.
BDrx

I'm sorry we will have to disagree on that one. The lumen rating for all bulbs are measured by measuring the light intensity at a distance of 12". You can Google that. I did.

Light also obeys the same inverse-square law that gravity and sound wave intensity follows. If you move a bulb closer to an object, it gets more light (measured by lumens per sq. ft.).

Note the difference between "lumens" [the bulb's output at 12"] and "lumens per sq. ft." [the amount of light hitting an object at x distance away]. It's the Illuminance (amount of light per unit area) that counts, which is related to the lumen rating of a bulb and distance it is from an object.

If you move a bulb closer, the light gets more intense. Try this:
Foot-candle - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Foot_candle)

To quote one piece from that link: "A source that is farther away casts less illumination than one that is close, so one lux is less illuminance than one footcandle. Since illuminance follows the inverse-square law ... <snip>"

Although you are correct in saying you cannot get more lumens from a bulb than it is rated for, I did not say you could. I said you can get more lumens/sq. ft. by moving the bulb closer.

Illuminance is what we used to call "brightness." It is a measure of lumens/sq. meter (also related to "lux" and "foot-candles" and "candellas").

Here is a link that explains illuminance: Luminance - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Luminance)

PS: I have checked out many many sites already. Want an example? Go here:
lumens per sq ft./please halp!!! - Grasscity.com Forums (http://forum.grasscity.com/absolute-beginners/281680-lumens-per-sq-ft-please-halp.html)

headshake
09-04-2009, 04:35 PM
well you can give all the links you want but the proof is in the pudding. i've seen my plants and i've seen your plants, so you can bring stephen hawking himself to my house to tell me the same thing and i'm not budging!


-shake

bractdoctor
09-04-2009, 07:18 PM
I follow what you are saying. Point made is that they are starving for lumens. I am not judging you, nor arguing. My point is this: If a person decides to run a show, ans is not legal (med patient or in a country where is legal), then you stand in most states the same risk for one or two small plants than 1-4 larger, more developed plants. Have fun, and enjoy your harvests! BDrx




coming soon. Blue Rhino 1947, Blue Dragon x Bluerhino 1947 x Blue rhino 1947


heheheheheh

420NLGuy
09-04-2009, 08:16 PM
Yes, light dissipates the farther you are from the source. Now we agree on that. Therefore the opposite is also true: light increases in intensity the closer you get to the source. Do we agree on that? If not, please tell me why you disagree.

There are many links to show this. Here are a few:

Inverse-Square law for light
Inverse Square Law for Light (http://hyperphysics.phy-astr.gsu.edu/HBASE/vision/isql.html)

Intensity: The Inverse-Square Law
Intensity: the Inverse Square Law (http://csep10.phys.utk.edu/astr162/lect/light/intensity.html)

Overview of Inverse Square Law of Lighting
Overview of Inverse Square Law of Lighting - AFB Senior Site - American Foundation for the Blind (http://www.afb.org/seniorsite.asp?SectionID=65&TopicID=298&DocumentID=4783)

CFL: Calculations and Room Design
CFL: Calculations and Room Design - Marijuana Growing (http://www.rollitup.org/cfl-growing/57297-cfl-calculations-room-design.html)

Can you tell me how many lumens/sq. ft. that a plant needs in flowering? I've read in many forums that it should be at least 30,000 lumens/sq. METER. That converts to 2800 lumens/sq. FOOT. That is the number I used to calculate the distance.

I also made a mistake in the distance. I said it was 2.6", but it really is 9". If you hold a 1560 lumen bulb 12" away, you get 1560 lumens. If you hold it 9" away (3" closer), you get 2800 lumens.

Here is the corrected calculations:
[attachment=o226702]

Notice that I have been putting my bulbs 2" away. That close results in a huge increase in lumens: 56,000 lumens at 2" away.

Don't believe it? Here is a screenshot of a little spreadsheet that calculates the lumens at various distances.

[attachment=o226703]

Note that the lumens at 12" is whatever the rating of the bulb is. That's because the lumen rating of all bulbs are measured at 12". So moving it closer gets you more lumens. Much closer gets you much more lumens. It's the inverse-square law in action.

The formula to calculate the lumens from a certain distance is:
L = (Lumen rating)/[Distance/12]^2

So if your lumen rating is 1560, then at 2" away, the lumens at the plant is: 1560/[2/12]^2 = 1560/[0.167]^2 = 1560/0.028 = 55,936 lumens.

At 12" away, it should equal the bulb's rating. So:
1560/[12/12]^2 = 1560/[1]^2 = 1560/1 = 1560.

PS: I'm not smoking anything when I write this. :rasta:



The bold parts are where I have no idea where you get any of the calculations or distance equations. Light dissipates the farther you are from the source, whats this multiplication of foot candles 100% per inch?

Give me a source, and I'll still probably say that it's wrong, but I'm just ponderous of where you got those numbers......


-C

ForgetClassC
09-05-2009, 04:40 AM
......
I also made a mistake in the distance. I said it was 2.6", but it really is 9". If you hold a 1560 lumen bulb 12" away, you get 1560 lumens. If you hold it 9" away (3" closer), you get 2800 lumens.

Here is the corrected calculations:
[attachment=o226702]

Notice that I have been putting my bulbs 2" away. That close results in a huge increase in lumens: 56,000 lumens at 2" away.......

That right there.....aside from the ratings of the bulbs(I'm not going to get into your "calculations" because apparently, math is different where ever you are) everything is false..... This bulb we are speaking of.....is it not round....therefore.....this bulb we are speaking of is not projecting all of these 1560 lumens, which by the way, is speaking of TOTAL LIGHT OUTPUT, are not going all towards your plants, let alone with those "reflectors" you have, but shake already explained those physics. So back to this bulb we are speaking of. If we take this bulb, and place it into an actual reflector, one that some how directs all of this light through a say 1" sq hole, and all of this light fell upon a single sq. foot and this bulb was placed 1 foot from this illuminated square foot, than there would be this 1560 lumens in this one sq. foot. But, since there is no magic reflector, people use numerous lights, with efficient reflectors, and still have them very close, due to the fact that CFL light can not penetrate the canopy, because it is not as intense as HID. I still have no idea what sort of formulas you are using.....but like I said, I think we know different math.....s?

-C


P.S. I type ALL of this, extremely baked.....

headshake
09-05-2009, 06:03 PM
Yes, light dissipates the farther you are from the source. Now we agree on that. Therefore the opposite is also true: light increases in intensity the closer you get to the source. Do we agree on that? If not, please tell me why you disagree.

There are many links to show this. Here are a few:

Inverse-Square law for light
Inverse Square Law for Light (http://hyperphysics.phy-astr.gsu.edu/HBASE/vision/isql.html)

Intensity: The Inverse-Square Law
Intensity: the Inverse Square Law (http://csep10.phys.utk.edu/astr162/lect/light/intensity.html)

Overview of Inverse Square Law of Lighting
Overview of Inverse Square Law of Lighting - AFB Senior Site - American Foundation for the Blind (http://www.afb.org/seniorsite.asp?SectionID=65&TopicID=298&DocumentID=4783)

CFL: Calculations and Room Design
CFL: Calculations and Room Design - Marijuana Growing (http://www.rollitup.org/cfl-growing/57297-cfl-calculations-room-design.html)

Can you tell me how many lumens/sq. ft. that a plant needs in flowering? I've read in many forums that it should be at least 30,000 lumens/sq. METER. That converts to 2800 lumens/sq. FOOT. That is the number I used to calculate the distance.

I also made a mistake in the distance. I said it was 2.6", but it really is 9". If you hold a 1560 lumen bulb 12" away, you get 1560 lumens. If you hold it 9" away (3" closer), you get 2800 lumens.

Here is the corrected calculations:
[attachment=o226702]

Notice that I have been putting my bulbs 2" away. That close results in a huge increase in lumens: 56,000 lumens at 2" away.

Don't believe it? Here is a screenshot of a little spreadsheet that calculates the lumens at various distances.

[attachment=o226703]

Note that the lumens at 12" is whatever the rating of the bulb is. That's because the lumen rating of all bulbs are measured at 12". So moving it closer gets you more lumens. Much closer gets you much more lumens. It's the inverse-square law in action.

The formula to calculate the lumens from a certain distance is:
L = (Lumen rating)/[Distance/12]^2

So if your lumen rating is 1560, then at 2" away, the lumens at the plant is: 1560/[2/12]^2 = 1560/[0.167]^2 = 1560/0.028 = 55,936 lumens.

At 12" away, it should equal the bulb's rating. So:
1560/[12/12]^2 = 1560/[1]^2 = 1560/1 = 1560.

PS: I'm not smoking anything when I write this. :rasta:


we must all be morons and you are a freaking genius!

"a foot-candle is how bright the light is one foot away from the source. A lumen is a way of measuring how much light gets to what you want to light! A LUMEN is equal to one foot-candle falling on one square foot of area.

"RADIANCE is another way of saying how much energy is released from that light source. Again, you measure it at the source."

"Illuminance is the intensity or degree to which something is illuminated and is therefore not the amount of light produced by the light source. This is measured in foot-candles again! And when people talk about LUX, it's illuminance measured in metric units rather than English units of measure. To reinforce that, LUX is the measurement of actual light available at a given distance. A lux equals one lumen incident per square meter of illuminated surface area. They're measuring the same thing, just using different measurement units.

"Nowadays we use the term CANDELA instead of candlepower. Candlepower, or CANDELA is a measure of how much light the bulb produces, measured at the bulb, rather than how much falls upon the thing you want to light up."

"But here's where it gets tricky. The further away you move the light from what you want to illuminate, the less bright the light seems! If you measure it at the light, it's just as bright. But when you measure at the object you want illuminated, there is less light! A Physics teacher is going to tell you that light measured on an object is INVERSELY PROPORTIONAL to the distance the object is from the light source. That's a very scientific and math rich way of saying, the closer you are to the light bulb, the brighter that bulb is. Or, think of it this way. You can't change how much light comes out of your light bulb. So, to make more light on an object, you have to either move the light closer, or add more lights"


you can find out more here (http://www.theledlight.com/lumens.html).


"Wattage is a measure of electricity consumption, that's all. Technically wattage has nothing to do with light (how much light does a 1000 watt hair dryer give off?), however if you are talking about wattage of bulbs, and the ratio of the amount of light given off by a certain type of bulb to the wattage it consumes is somewhat predictable, then sometimes we talk about wattage as if we were talking about light intensity.

Lumens is a measure of light intensity at a fixed distance of one foot on a fixed area of one square foot. Furthermore, lumens measures only certain (visible to humans) frequencies of light. But again, the relationship is somewhat linear so we often use the term lumens when talking about light intenstity. Lumens is getting closer to the concept, but in reality lumens is a standardized measure for comparing bulbs one to the other, not for measuring how much light is being given off.

For example, take a bulb rated at 10,000 lumens and move it half the distance closer to the plant, and what happens to the lumens? Nothing -- it's still a bulb rated at 10,000 lumens. But as we know that light intensity is inversely related to the square of the distance, moving the light to half the distance increases the light intensity four-fold."


-shake

Rusty Trichome
09-07-2009, 02:00 PM
Not trying to pick on anyone, but I saw the word reflector mentioned in the same sentence as CFL's...


So back to this bulb we are speaking of. If we take this bulb, and place it into an actual reflector, ...with efficient reflectors, and still have them very close, due to the fact that CFL light can not penetrate the canopy...
The 26w CFL's don't put-out enough lumens to be effective in a reflector or hood. The distance from bulb to reflector, added to the distance from that reflector surface to the plant...is too far for the light to travel and still be effective.

In my opinion, CFL's in reflectors are basically a waste of money and they trap heat. (which we have convienently placed close enough to burn the plants) What would you gain in reflected lumens at a bulb distance of 4 inches, when the bulb is an additional 2 inches from bulb? (hint: it's not even worth doing the math it would take to figure it out)
Higher wattage CFL's (and HID lighting) would benefit from the use of reflectors, but their effective light extends much further than the 26 watters.

Regardless of the reverse inverse double half-gainer with a half-twist law...does anyone in here doubt that a 26w CFL is ineffecient and ineffective at 12 inches? How about 8 inches? I'd rather add another bulb or two, and not worry about it.

ForgetClassC
09-07-2009, 10:37 PM
I haven't used reflectors, but I know some of those fancy more expensive growlights come with them. I've seen a weird Arizona Iced Tea can reflector, but haven't bought or used one that looks nice or worth it.