yellow leaves and PH questions

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shahomy

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Hello
My leaves always turn yellow(then eventually crispy brown), before halfway through bloom...i`m thinking they need nitrogen...
But, is it not enough being given, or is there a nutrient lockout from PH maybe?
Here`s my setup...
7.5x8 bloom room w/ 2 1000watt HPS in basement
5 gal smart pots
humbolt "mix" peat moss inert media-Ingredients:

The Humboldt Mix contains a blend of 60-70% Canadian Sphagnum peat moss, horticultural grade perlite, dolomitic lime and Yucca extract.
http://www.humboldtnutrients.com/blog/humboldt-mix/
humbolt nutrients - 2-Part Basic Feeding Schedule
well water - has rotten egg sulfer smell occasionally
- also has tannins, was told this by the local water dept,15 years ago

Here`s my feeding schedule, 1 gal ea week(given all at once)

http://i752.photobucket.com/albums/xx168/shahomy/humbolt-1.png
picture.php


Bought a General hydroponics PH kit(test kit, PH up and down) and have done many tests, and what i see is that i have very alkaline water...which doesn`t make sense cause what i read about tannins is they are acidic...
Judging by this pic, i`d say i`m over 7 on the PH...
picture.php


And here`s a pic of a plant at 4 weeks into bloom...
picture.php

picture.php


Argg... it`s getting late... i`ve got more information, i`ll edit and finish this post in the morning
Guess i gotta post it, i don`t see no way to save it...
 
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That is typical nitrogen loss that occurs during flowering. The pH is definitely too high if it is at all above 7.0. Yeah the tannic acid should make it lower than that but the sulfur could be keeping it high. I believe the Humboldt nutes are "organic" and that may be what has been saving you from further issues if the pH is indeed over 7.0.

I would say that you could make or buy a nutrient tea with nitrogen in it and give them light doses to see if it will bring the leaves back but it may be too late for this go around. The problem with adding nitrogen after flowering is well under way is that the added nitrogen, if too much, can cause the flowering to halt.

You definitely need to get the pH down to around 6.5-6.7 every time, and that may help the problem, if not this time then maybe next time.
 
Multi You are right. I just looked at what I typed and realized that I didn't say that right at all.:doh: I meant that the yellowing like that is fairly typical for late flowering with some plants and feeding types. But the problem appears to be the pH being too high. I also am not real big on trusting the pH drops myself but DGF uses them and said they are very accurate with his pH pen. I am afraid that the color could be pulled off by a chemical interaction when used with nutrients. In clean water they might be fine. :)
 
people again get confused about yellowing saying its normal and it is being proven over and over again that its not the normal,,
Having plants yellow off IMO it is wise pending on how long you vegged that you flush your plants prior to flower getting rid of any salt build ups as well as making sure your ph is in check.
Although nitrogen is needed in all phases of a plants life in and 99 percent of all bloom food has sufficient but when a person flips to 12 -12 there is a 2 week period where plant switches over so adding half veg and half bloom nutes is recommended this probably will help with the sudden yellowing off.
Cal mag should be used in flower mode more as it is 2-0-0 and with bloom nutes it will bring up N levels
Only reason plants will start yellowing off this quick is 1 PH in medium has dropped from giving plants to much food crucial to keep ph in check specially in bloom phase picture is 4 - 5 weeks flowering i always Flush plants getting ph in check prior to the crucial bloom phase once your plant is in bloom there is no correcting plants 3 - 5 weeks in bloom nice and green

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its not the normal
I couldn`t agree with you more...your pics are what i want mine to look like. The bud is really good to smoke, but i can`t help wondering how much bigger and better it would be , if i had some leaves to keep it going!
Any suggestions on a good meter? EC,PH,PPM,TDS? name brand, model #
?
I water every other day or 2 days, 1 gal each plant, and for the last week and a half i`ve been adding .625 ml of ph down to gal of water.
When i make a gal of juice, i don`t add any ph down, as i`ve tested it and the nutes bring it down considerably.
Last 2feedings i`ve increased the Master A&B by 2ml each. and Ginormous by 1 or 2 ml. I`ll be checking for nute burn...

Having plants yellow off IMO it is wise pending on how long you vegged that you flush your plants prior to flower getting rid of any salt build ups as well as making sure your ph is in check.
This is interesting, and something i`ve never done... how do you do it?
And i`ve been vegging for 4-6 weeks
Put the plant over large container and dump 2 gals water through it?
Is there a test for this salt buildup? like electronically?(pen/meter)
So, around 6- 6.5 for ph? regardless of plain water or mixed with nutes?

Thanks everyone
 
ok i just read up on your nutes.

you are feeding with hydroponic nutes, so therefore you must ph to hydro standards. nutrients are locking out and you need to flush your medium with a 1/4 strength mix. make sure to properly ph to hydro standards(5.3-6.3), not soil(6.0-7.0).
 
I don't think its neccessary to feed half and half during transition and have never heard anyone advocate this before.

I use GHE flora series, only using Grow in early veg before switching to Lucas mid to late veg and lucas/cal-mag during transition.






http://www.humboldtnutrients.com/blog/master-a/





While the Humbolt A&B nutes are blended for use in "any" medium I'd prob shoot for a pH of around 5.8, im sure once you get your pH in check you will see improvements.

As for flushing the rule of thumb is 3 times the volume of your container and i'd personally do this with @ 1/2 strength of your current mix, then back to your normal strength.


What I do is start 12/12 i do not switch nutes the first day of 12/12. The first 5 - 10 days of 12/12 in my opinion is still in the VEG cycle, transitioning and some Nitrogen is needed to maintain a healthy plant. And that is where many threads you see yellowing off 2 weeks - 4 th week
I continue my VEG nutes first week in flower second week keeping same ppm mix half veg / half bloom .. gradually changing over to the Flowering nutes.
 
I'm still some what confused by your decision to use a half and half veg and flower nutrient mix during first 5-10 days of flower, when "you believe" that 99% of bloom/flower nutrients have sufficient N in them.

I do not see any advantage to your method and feel that you're overcomplicating the transition from veg to flower by mixing half and half for the first 5-10 days of flower.

this is what i believe from years of growing out door and in door that Increasing the levels of nitrogen during the vegetative stage can strengthen and support your roots, enabling plants to take in more water and nutrients. This allows a plant to grow more rapidly and produce large amounts of succulent, green foliage, which in turn can generate bigger yields, tastier buds, and a crop that is more resistant to pests, diseases.
Now with that said Nitrogen is needed in all stages of growth Period veg state like mentioned above is when plant explodes in growth pre flowering ( transitional stage ) your plant feeding should remain pretty much the same for the 1st feeding and for second feeding introducing the Bloom nutrients with a mixture of veg

Preflowering

This is a quiescent period of one to two weeks. The plant is beginning a new program of growth as encoded in its genes. The old system is turned off and the new program begins with the appearance of the first flowers. this stage is not Flowering stage ????? as flowers have not set
Now were into 3rd week ?????
Flowering has started were introducing just bloom nutrients,,,, Now As many can agree??? most bloom nutrients you buy still show a Nitrogen count now you can look at all of them they will always be less Nitrogen then Veg nutrients....
One begins to wonder well why is that these big companies that have spent probably millions on scientific data proving that Nitrogen is needed in all stages but less in bloom, well i will just go with that Enough said
Plants use a fundamentally different "life strategy" from animals. Animals are more or less self-contained units that grow and develop to predetermined forms. They use movement and choice of behavior to deal with the changing environments. Plants are organized more as open systems - the simple physical characteristics of the environment, such as sunlight, water, and temperature, directly control their growth, form, and life cycles. So keep that in mind Once the seed sprouts, the plant is rooted in place and time. Since growth is regulated by the environment, development is on accordance with the plant's immediate surroundings. When a balance is struck, the strategy is a success and life flourishes.

Behavior of a plant is not a matter of choice; it is a fixed response. On a visible level the response more often than not is growth, either a new form of growth, or specialized growth. By directly responding, plant in effect "know," for example, when to sprout, flower, or drop leaves to prepare for winter.

multifarious ???? You mentioned you never herd of mixing ?? Both Veg and bloom nutes in pre flowering stage ???? I also think you mentioned you use GH as well ???? here copy and paste from GH site

Do I use MaxiGrow and MaxiBloom at the same time?

Answer: Yes and no. The Maxi series is designed to use one part at a time, but in a time of transition it may be beneficial to mix the two at half strength each (makes a full strength nutrient solution). Use MaxiGro in the vegetative stage and MaxiBloom in the fruiting/flowering stage.

Note: If your plant is not fruiting or flowering plant, MaxiGro is all that you will need to use.

For further information, refer to our Maxi Series feed chart.

Do I use FloraNova Grow and FloraNova Bloom at the same time?

Answer: Yes and no. The FloraNova series is designed to use one part at a time, but in a time of transition it may be beneficial to mix the two at half strength each (makes a full strength nutrient solution). Use FloraNova Grow in the vegetative stage and FloraNova Bloom in the fruiting/flowering stage.

Note: If your plant is not fruiting or flowering plant, FloraNova Grow is all that you will need to use.

For further information, refer to out FloraNova feed chart. ENOUGH SAID LOL BOTTOM line ??????? it Crucial to have plants in tip top shape entering flowering this alone will make or break all your hard work ...

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multi you forgot this one the most important funny

http://generalhydroponics.com/site/index.php/resources/faqs/nutrient_and_flora_questions/
now if i either copied or pasted anything its really irrelevant but it proves a point i am sure many on here will mix both and imo its a smart choice really probably. can be many beneficial to this one being maybe it helps with stretching of plant , and obviously yellowing of plant in transition stage , And what is more complicating instead of mixing 200 ml of one part mix 100 ml of both parts veg and bloom both A n B products
we all can say we got over 25 years of farming and growing mj but again different varieties require different strengths for instance when i grew up farming we grew different products corn wheat, barley etc we would apply phosphates as per our soil tested samples pretty simple really and funny thing is they apply it as well
sure we still spread manures in fall and in spring but soil tests are crucial for field yields , PERIOD we still sell all types of plants in our business i still get my own peat based soilless mix made 2 super B trailers that i place in sea cans on property so please lets not talk about our experience in horticulture its swaying off the topic

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copy and paste other peoples work/words and do not, on most occurances, quote the original poster. Many people would consider this tantamount to stealing and or trying to pass off other peoples words/work as your own (same difference really)


I concur. Give the credit where it's do!!! after going through this forum and some the other posts from this member I start wonder about his pics being theirs.
 
You definitely need to get the pH down to around 6.5-6.7 every time, and that may help the problem, if not this time then maybe next time
Seriously Hush, I`m not trying to pick on ya...especially since your MIA at the moment.
I am sincerely grateful for anyone who takes time to post and try and help me...and in all fairness no one else caught what I think is a mistake.
My original post is about yellowing and ph questions, my water being about 7.2-7.3.
Well no one has mentioned the ph of my medium, which it turns out is very low being peat.
So since then I`ve bought a bluelabs guardian and soil probe and my ph ranges from 5.4 to 5.9 . The high ph water barely changes it...I checked it tonite, it read 5.6...gave a gallon of 7.3 water to the plant , and after an hour it`s at 5.7.... so I don`t believe I should be lowering the ph of my water. Should I raise it with ph up? how much? 8.2? 9.2? remember the water is barely affecting the peat now.
Also,there is 2 full cups of espoma lime in each 5 gal smart pot. This I believe has helped, not as much yellowing, but still my ph is to low...I think?
I`m soilless, so what should my ph be of my medium?
Can it be raised or is it not possible?
Is anyone using peat able to keep it in the low 6`s?

these are week 6 mostly(the pics) gave week 7 nutes Monday nite

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what is the ppm of the nute mix, and what is the ph and ppm of the runoff? from my understanding approximately 5.5-6.5 is for soil less but I am not understanding your watering. are you hand watering? how many times a day? do you oxygenate the fluids? I ask because i am about to use ebb and flow and it floods and drains 1-2 times a day veg and 3-4 times a day for flower, but they recommend adding air stones to keep the fluids oxygen rich
 
Hey Shahomy; you are fairly right to call me on my advice from the last time. I didn't really understand the nature of the peat based medium and how the pH is affected by it. I was thinking that you were pretty much organic in organic soilless medium. I haven't grown that way so I was trying to extrapolate information. I still don't have any real good advice on this one as you are in a soilless setup which is really tricky to do without having pH issues. I have tried it a couple times and was ready to pull my hair out.

The problem that I have found with soilless mediums, with synthetic nutrients(I haven't tried organic in soilless) is that you get element buildup really quick if you don't flush real regular. That buildup can cause toxicity, or it can really screw with the pH. That may be what is happening with yours. By the time they get halfway through bloom, the medium has built up a lot of chemicals that could be pulling the pH or binding with the nitrogen and locking it up where the plants cant use it.

It seems to be a consensus among the growers that soilless pH should be real similar to hydro. However, I think it can be a little higher depending on the type of soilless medium you are using, but I would shoot for 6.0 to start. Don't try to adjust the water first when mixing the feeding solution. Mix your solution and then check the pH for a reference point. Then let it aerate for a few hours and check it again. then adjust it to 5.8-6.0 and then let it sit and aerate for a couple more hours to see if it will change. You will probably see it rise a little more from the aeration. If it moves away from the 6.0 by more than .2 adjust it back.

I suspect you will have to experiment with the pH in order to keep it where it needs to be. I also think you will find it will benefit you to flush the medium real well when you reach the change over from veg to flower. I do this in my hydro setup as I use coco coir in pots kind of like a flood and drain. I flush the whole system with straight water at the end of the 3rd week in flower when I cut off all grow nutrients. It prevents any toxic buildup which I have had occur before. I hope this helps you :)

PS. yeah I have been MIA for a while but I am going to try to stick around a little more now. :)
 

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