Possible N deff (pictures)

kieahtoka

Well-Known Member
Well I've got a plant on day 21 of flowering and it's yellowing extremely fast. I was reluctant to say it was an N deff because I had overdosed it with blood meal early on so I thought it would still be working. I flushed her out to make sure it wasn't a salt buildup that was locking out any nutrients. So far the yellowing has reached halfway up the main stem, and now it is starting on the lower branches. I have recently fed with an 8-7-6 indoor plant food to see if this might help. I know I won't see a different yet I just wanted a second opinion.
 

kieahtoka

Well-Known Member
I've got some blood meal in a gallon jug, bubbling for tomorrow's watering. I hope that helps some.
 

babygro

Well-Known Member
geez, you got here fast, thanks.
Yeah I posted too quickly - before you'd posted your pics. I just happening to be here looking at the time.

It's definitely N def, do you have any Fish Emulsion? That's quite good for a quick fix of N.

I posted quite a long post about NPK and feed levels this afternoon in answer to a newbies question. Might be worth taking a read of it when you get a moment, it's quite a long post, but it talks about NPK ratios and typical EC feed levels, you might find it interesting.

I'll find the link if you like.
 

kieahtoka

Well-Known Member
Please do I'd like to read that. I'll try and go get some fish emulsion tonight. If I can't would the blood meal tea work just as well?
 

babygro

Well-Known Member
I've got some blood meal in a gallon jug, bubbling for tomorrow's watering. I hope that helps some.
I'm not sure how useful Blood and bone meal is to be perfectly honest, although I have little experience of it used as a 'tea'.

I've avoided using it for two principle reasons - firstly because of the BSE problem we had in this country (UK) and the possiblity of pathogens remaining in the bone and blood. Secondly because used as is (ie not in a tea) it's just too slow acting to be of any use. It's great for gardens and allotments, where it can release it's nutrients over a much longer time frame, but for pot plants, who are going to use up their N reserves pretty quickly, it just doesn't release Nitrogen at a fast enough level - the plants are havested before they get any benefit.

Blood and bone is really cheap in Garden Centres and always on special offer over here (ie buy one tub and get one free) - principally because no one buys much of it for the reasons I've given, particularly the risk of viral and pathogenic contamination from it.

In my view you're far better off getting something like Fish Emulsion, which like Blood and bone is sourced from organic sources and releases it's nutrients at a much faster rate.
 

babygro

Well-Known Member
Please do I'd like to read that. I'll try and go get some fish emulsion tonight. If I can't would the blood meal tea work just as well?
I'm not sure about the blood meal as I said in my post, I have no experience of it used as a tea - I don't know if that speeds up it's nutrient release or not. I'll have a look around and see if there's an answer.

Here's the link and it's not a cut and paste either ;)

https://www.rollitup.org/215579-post4.html
 

babygro

Well-Known Member
If I can't would the blood meal tea work just as well?
Well it seems blood meal is fast acting and bone meal is the slow acting one. I really can't comment on it to be honest, as I have little to no experience of blood meal.

I still feel Fish Emulsion is a better bet as it's faster acting, organic and immediately available to the plants.
 

kieahtoka

Well-Known Member
I read it and was intruiged about the EC/TDS part of it. I didin't know it had that much to do with the nutrient uptake of plants unless it was in a hydroponic grow situation. So, I bought an EC/TDS meter.
 

babygro

Well-Known Member
I read it and was intruiged about the EC/TDS part of it. I didin't know it had that much to do with the nutrient uptake of plants unless it was in a hydroponic grow situation. So, I bought an EC/TDS meter.
EC works in the same way in a nutrient solution whether it's being used in hydro, soil, soiless mixes etc - the princple remains the same.

It's just a lot more critical in hydro, hence people take more notice of it, but it's still equally applicable to soil grows.

With your EC meter, you can now get your soil feedings absolutely bang on, and just as importantly check your irrigation water for TDS.
 

kieahtoka

Well-Known Member
That's good, I got it on ebay since they are usually the cheapest. it said 0-1999 ppm. I don't understand how that related to what you said about .2 being good and over .6 being too much TDS.
 

babygro

Well-Known Member
That's good, I got it on ebay since they are usually the cheapest. it said 0-1999 ppm. I don't understand how that related to what you said about .2 being good and over .6 being too much TDS.
Interesting you've just asked a similar question to someone else on that other thread! I'll try and post a reply to the other question tonight and a formula for converting NPK ratios into ppm and EC, which may help.

There is a chart floating about that converts ppm to EC, TDS and ppm values, unfortunately I don't have it in scan form - only in book form. Someone in the Hydro section may have a scan of it. Just to complicate matters, each EC manufacturer has its own ppm values!

From my book -

EC = Hanna, Eutech, Truncheon

0.1 EC = 50ppm, 64ppm 70ppm
0.2 EC = 100ppm, 128ppm 140ppm
0.3 EC = 150ppm, 192ppm 210ppm
0.4 EC = 200ppm, 256ppm 280ppm
0.5 EC = 250ppm, 320ppm 350ppm
0.6 EC = 300ppm, 384ppm 420ppm
0.7 EC = 350ppm, 448ppm 490ppm
0.8 EC = 400ppm, 512ppm 560ppm
0.9 EC = 450ppm, 576ppm 630ppm
1.0 EC = 500ppm, 640ppm 700ppm

You can pretty much calculate all the other higher values from this chart (eg 1.1 EC would be 550ppm on the Hanna scale).

So by using the chart, let's assume you use a Hanna EC meter, 0.2 EC would be 100ppm and 0.6 EC would be 300ppm. So what I was saying in regards to the TDS of the irrigation water, if it has a ppm of 100 or less on the Hanna scale, then it should be fine as it is, if it's over 100ppm, then you might want to think about mixing it with distilled or RO water (which has an EC of 0, or should do, depends on how many stages your RO machine has) to enable you to use sufficent quantities of nutrient in your solution without raising the overall EC or ppm to too high a level.
 

kieahtoka

Well-Known Member
Well mine should come with a book containing these values. I'm pretty sure it's not any of the brands you mentioned. Unfortunately I don't think it will be calibrated and probably won't come with a solution like a ph meter does. This mightbe a stupid question but distilled water should have a ppm of 0 right?
 

babygro

Well-Known Member
Well mine should come with a book containing these values. I'm pretty sure it's not any of the brands you mentioned. Unfortunately I don't think it will be calibrated and probably won't come with a solution like a ph meter does. This mightbe a stupid question but distilled water should have a ppm of 0 right?
Distilled water should have a ppm of 0 yes - it's effectively the same as Reverse Osmosis water. However, using 0 EC or ppm water can be just as bad as too high an EC or ppm irrigation water but for the opposite reason - you're taking out too much of the essential nutrients like Magnesium and Calcium and you're then in danger of causing Mg and Calcium deficiencies. The reason you see few if any Calcium def's is because the majority of tap water (which most people use) has so much Calcium already in it. The only time you may get it is with soft water - which I beleive kp has problems with.

So you need to strike a balance between the two and if your tap water ppm is too high to use as it stands, then mix it with the distilled or RO water in 50/50, 80/20 , 70/30 or whatever works best ratio's (RO/Distilled to tap) depending on how hard your tap water is or how high the EC or ppm values are.

With an EC meter, you should be able to get the mix of the two just right.
 

kieahtoka

Well-Known Member
Well I wasn't planning on using this water for my plants, just as a calibration technique. Knowing the water here it probably has a very high EC. Although I use water filtered through activated carbon but this doesn't change the EC much, does it?
 

babygro

Well-Known Member
Well I wasn't planning on using this water for my plants, just as a calibration technique. Knowing the water here it probably has a very high EC.
Well you can use that to your advantage, just mix it with your distilled water. Distilled water contains no dissolved salts, therefore it contains no Magnesium or Calcium - two micro nutrients Cannabis uses in fairly high quantities. What you have to do however, is make sure your water doesn't have too high a TDS content that can have the reverse affect - locking Mg out of the soil.

Although I use water filtered through activated carbon but this doesn't change the EC much, does it?
About 1.0 - 1.5 EC, not a great deal but a little.
 

VirginHarvester

Well-Known Member
This brings up two questions I have:

1) What causes salt buildup; what percentage of plants get it; and is it less likely in a soil grow outdoors?

2) How much ferts is enough? I'm just following the recommended doses on the labels more or less.
 

babygro

Well-Known Member
1) What causes salt buildup;
Nutrient feeds and salts in the irrigation water.

what percentage of plants get it
Any that get over-fed and/or have a high EC tapwater/irrigation water.

and is it less likely in a soil grow outdoors?
Indoors, outdoors, any plant in a pot gets it if the feeds are given at too high an EC level and particularly with chemical based salt fertilisers.

2) How much ferts is enough?
If I had an easy answer to that, I'd bottle it and make a fortune!

Track back through this thread and take a look at the link I provided earlier.
 
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