Signs of Underfeeding?

[Crusader Rabbit]

You two should get a room.

 

[stihgnobevoli]

im going to get one right now, lock myself in and shoot myself in the face. should prevent arguing semantics in the future.

 

[SeaMaiden]

Alright stihg, here you go.

http://5e.plantphys.net/article.php?ch=t&id=289
From the mother site: http://5e.plantphys.net/

Scroll down to Nitrogen, but I'm going to quote it anyway. Please note the specific mention of petioles.

Nitrogen. The chlorotic symptoms (see Web Figure 5.1.D) shown by this leaf resulted from nitrogen deficiency. A light red cast can also be seen on the veins and petioles. Under nitrogen deficiency, the older mature leaves gradually change from their normal characteristic green appearance to a much paler green. As the deficiency progresses these older leaves become uniformly yellow (chlorotic). Leaves approach a yellowish white color under extreme deficiency. The young leaves at the top of the plant maintain a green but paler color and tend to become smaller in size. Branching is reduced in nitrogen deficient plants resulting in short, spindly plants. The yellowing in nitrogen deficiency is uniform over the entire leaf including the veins. However in some instances, an interveinal necrosis replaces the chlorosis commonly found in many plants. In some plants the underside of the leaves and/or the petioles and midribs develop traces of a reddish or purple color. In some plants this coloration can be quite bright. As the deficiency progresses, the older leaves also show more of a tendency to wilt under mild water stress and become senescent much earlier than usual. Recovery of deficient plants to applied nitrogen is immediate (days) and spectacular.

Phosphorus. These phosphorus-deficient leaves (see Web Figure 5.1.E) show some necrotic spots. As a rule, phosphorus deficiency symptoms are not very distinct and thus difficult to identify. A major visual symptom is that the plants are dwarfed or stunted. Phosphorus deficient plants develop very slowly in relation to other plants growing under similar environmental conditions but without phosphorus deficiency. Phosphorus deficient plants are often mistaken for unstressed but much younger plants. Some species such as tomato, lettuce, corn and the brassicas develop a distinct purpling of the stem, petiole and the under sides of the leaves. Under severe deficiency conditions there is also a tendency for leaves to develop a blue-gray luster. In older leaves under very severe deficiency conditions a brown netted veining of the leaves may develop.

If you read the whole page you'll note that this mention of reddening of the petioles is not made for all deficiencies.

Sorry it took me so long to get to you on this, but it was a challenge I could not let go. I have a LOT more, from similarly credible sources, that will prove veracity of my and FoCo's claims.

This is not semantic quibbling, either.

 

[someotherguy]

this site has much useful information for anyone caring to look.

Greenhouse Grower

...and arguing hurts us all.

and thanks to all the ignorant fools who tagged my post suggesting someone actually acknowledge anothers help as 'not helpful', it makes me feel good knowing i've offended the assholes, lol.

peace, SOG

...and i still say if someone has helped you it is only right you should acknowledge that help, ...especially if you hope to get any help in the future.

 

[Crusader Rabbit]

Those charts are extremely helpful to me right now. Thanks

Reads like acknowledgement to me.

 

[SeaMaiden]

You wanna know what's most important to me? Seeing people succeed, resolve their problems, learn, grow. That's the best acknowledgement for me.

There is little to debate, IMO, with specific regard to what stihg and FoCo are discussing (debating, arguing, whatever). FoCo is correct, stihg is not. Not only does the science bear this out, but the grows bear it out as well.

I'd also like to say that while learning in and of itself can be difficult enough, one must also endeavor to ensure the source of information holds veracity, i.e. is truthful and provable. I learned this when I first decided to start keeping saltwater fishes, some folks knew their shit and could support it, while others simply didn't. It took me a while and a few fish deaths to learn how to tell the difference, it is a skill well-honed I believe.

And so I want to make an acknowledgement directly to FoCo--I totally learned something from you. I didn't make the connection to N via reddened petioles that I had made with P from my own research, but when I went to look up stihg's challenge, there it was. I now have yet another useful tool in my toolbelt of knowledge. Thank you.

 

[stihgnobevoli]

the part where my post was deleted. classic.

 

[growyourboat]

OK guys....there is no need to continue this argumentation....BOTH of you are right.....but I would say that stihgnobevoli is correct in saying that the leaves are a more accurate/easy to read indicator. Just look at the color of the leaf. Yes, nitrogen deficiency can cause purpling petioles, but so can a hundred other things, any kind of stress really...and as stihg points out, some strains will purple up at the slightest stress.

I look at the leaves, and how dark or light green they are tells me everything I need to know in a second.

OP: if your plant is being underfed, the leaves will be a pale green, almost yellow. (Yellow if they really are way underfed.) An OVER-fed plant will have dark, dark green leaves, which will then "claw" up from excessive nitrogen.

 

[JJScorpio]

the part where my post was deleted. classic.

What's classic is getting so upset that you have to swear and be rude to the point of having the post deleted.

 

[SeaMaiden]

Growyourboat, did you miss my post #23 and link entirely? Purpling/reddening petioles are *not* an indicator for 'a hundred other things', it's primarily an indicator of P and N issues. Please, read the link, it's an excellent source of information, truly. There is nothing to debate because stihg is incorrect in his assertions, and has been proven so.

 

[stihgnobevoli]

no the classic part is how my posts are always getting deleted but never anyone else, im not the only one swearing. just the only one that you go after.

and i didn't realize there was a no profanity rule on this server? you keep telling me no attacks. i didn't attack anyone, i refrain from attacks. but whatever.

also seamaiden the only thing you have proved is that you are very selective when it comes to reading.

"hey heres a whole 2 paragraphs all about the signs in the leaves but ignore that. see purple petioles. "

i hope you can manage to read this before it gets deleted for whatever arbitrary reason JJ comes up with.

 

[growyourboat]

Your link is wrong. Cold weather causes purple petioles too.

Bottom line......in CANNABIS..... Leaf color is a far better and more reliable indicator.

 

[Crusader Rabbit]

All the signs a plant gives us are worth reading.

 

[FoCo(No.Co)]

Bottom line......in CANNABIS..... Leaf color is a far better and more reliable indicator.

Obviously the leaves will show symptoms from deficiency. You are totally missing the point though.

The petioles change color before the leaves show symptoms, which allows you to fix the problem before it does any real damage. If you wait for the leaves to turn yellow and start to die then you are too late! Your deficiency has already screwed things up if leaves are dying.

Watching petiole color allows you to catch the problem earlier, which is why it is useful.

I'm not telling anyone to ignore leaf color, I'm just letting you know that the petioles will show symptoms before the broad part of the leaf will. Period.

 

[stihgnobevoli]

my plant is all green, but the petioles are purple and the whole stem. in fact everything is purple except the leaves. what should i do to fix this problem good sir?

 

[growyourboat]

^ exactly. Purple petiole is not a smoking gun indication of a damn thing. In practical use, it's useless in certain circumstances, for example if you allow your flowering room to get cold at night so the plant will purple up.

I don't wait for my plants to turn yellow before feeding. I simply feed them with every watering. The resulting leaf color and appearance tells me exactly what I need to know, accurately, every time, about what the needs or doesn't need. The leaves don't lie.

 

[FoCo(No.Co)]

my plant is all green, but the petioles are purple and the whole stem. in fact everything is purple except the leaves. what should i do to fix this problem good sir?

^ exactly. Purple petiole is not a smoking gun indication of a damn thing. In practical use, it's useless in certain circumstances, for example if you allow your flowering room to get cold at night so the plant will purple up.

I don't wait for my plants to turn yellow before feeding. I simply feed them with every watering. The resulting leaf color and appearance tells me exactly what I need to know, accurately, every time, about what the needs or doesn't need. The leaves don't lie.

You guys obviously didnt read the very first post I made in this thread-

*note, this is a general rule that holds true most of the time, however some strains(particularly purples) will show dark colored leaf stems because of genetics not underfeeding.

 

[growyourboat]

You guys obviously didnt read the very first post I made in this thread-

Oh, you mean where you helpfully pointed out that your petiole reading method is irrelevant and wrong in many cases?

PURPLE = STRESS. It does not fucking mean "needs nutrients".....though it CAN be a result of that....because nutrient deprivation IS a form of stress.

Look at the very pictures you posted. Anyone with eyes, who has looked at enough plants, can tell just by the color of the leaves that the third plant needs nutes. Compare the three pictures! Do you not see the difference in shade and luster? The purple shit is irrelevant. That could be caused by temperature, by light, by genetics, by a hundred other factors, as I already stated in my first post, before your dumb ass blew this up into a (yet another!) shitfest of jackassery.

Listen to what we're fucking saying. It's clear you've probably never popped more than 20 cannabis seeds in your life. Stop coming into threads and trying to argue knowledgeable people into the ground about stuff they have firsthand experience with, only to discover (surprise!) that you were a moron all along, long after legions of newbies have been misled by pages full of your loud mouth and lack of knowledge. (This is why they call it "knowing just enough to be dangerous.")

Stop googling shit on the Internet and copying and pasting like that means anything. Anyone can do that. It takes someone with an actual clue to think critically and understand what they're reading.

 

[SirTOKESalot]

Useless thread.

 

[FoCo(No.Co)]

Stop coming into threads and trying to argue knowledgeable people into the ground about stuff they have firsthand experience with, only to discover (surprise!) that you were a moron all along

Ed Rosenthal, dude. Ed Rosenthal.

Ed Rosenthal-

"Nitrogen. N is the most common deficiency of cannabis indoors or out. The first sign is a gradual, uniform yellowing of the large, lower leaves. Once the leaf yellows, necrotic tips and areas form as the leaves dry to a gold or rust color. Symptoms that accompany N deficiency include red stems and petioles, smaller leaves, slow growth, and a smaller, sparse profile."