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Phosphorus deficiency, day 35 of flower, help

A

apeshot

Member
Hi everyone. I am growing White Beelze Bubba by Karma in an organic soil mix. I am at day 35 of flower. The lower leaves are showing a clear phosphorus deficiency.

This picture is not from me but it looks exactly like this:

P.jpg


The soil mix has always had an abundance of nitrogen for this particular plant as evidenced by slight clawing / downward taco'ing of some leaves and a very deep green colour to the foliage. Nothing I can do about that this late in flower as I am, and have from the beginning, only feeding plain water.

My question is, can too much N lock out P? Or could it be that my soil is simply deficient in this element, despite being heavy on the N?

My mix is:

2 parts Seagreens Premium Organic Potting Mix
http://www.seagreens.com.au/products/seaweed_potting_mix/specifications.htm

1 part Gardener's Friend Organic Compost
http://www.purelivingsoil.com.au/compost.html

1 part perlite

Then I amended with:
1 Tb Blood and Bone per gallon
2 Tb Dolomite lime per gallon

My long term goal is to get rid of the perlite and build a soil that I can recycle, adding in what I need to after each run and letting it cool for a while.

I thought the compost I added in would have enough P, but it may not.

But in this case I am wondering, should I top dress with chicken manure to correct the Phosphorus deficiency? Or use a bloom fertilizer with a higher ratio of Phosphorus?

Any help would be appreciated. This is a long term focus for me as I started in Coco hempys and peat/perlite with synthetic nutes. I am committed to going organic but sometimes it's discouraging when this sort of thing happens. All part of learning though I guess.
 
T

TanzanianMagic

Well-known member
Veteran
apeshot said:
My mix is:

2 parts Seagreens Premium Organic Potting Mix
http://www.seagreens.com.au/products...ifications.htm

1 part Gardener's Friend Organic Compost
http://www.purelivingsoil.com.au/compost.html

1 part perlite

Then I amended with:
1 Tb Blood and Bone per gallon
2 Tb Dolomite lime per gallon
Click to expand...
I don't see any K or potassium. One of the functions of potassium is to increase the uptake of nutrients.

Basically when you make your own mix, you have to take into account that you get your primary nutrients N, P, K, secondaries Ca, Mg, Si, S and trace nutrients.

N - bloodmeal
P - bonemeal
K - vinasse, wood ash, molasses to some degree

Ca - lime
Mg - Maerl, magnesium lime (also has calcium)
Si - silica sand (like Mineral Magic), sand, stinging nettle
S - vinasse, epsom salts (also has Mg)

Also:

Chitin - worm castings
Triacontanol growth hormone - alfalfa meal/pellets (also has N)

Trace elements - rock dusts, seaweed (might have sodium in it so watch out).

I'm trying to replace all animal products other than worm castings with plants and rock dusts. I'm using fermentation with molassis and water to make my own liquid nutrients from plants.
 
A

apeshot

Member
Is there anything else I can use for P instead of bonemeal?

Where I live there is only "Blood and Bone" available, and I feel it has a high N content, which I don't really need.
 
T

TanzanianMagic

Well-known member
Veteran
apeshot said:
Is there anything else I can use for P instead of bonemeal?

Where I live there is only "Blood and Bone" available, and I feel it has a high N content, which I don't really need.
Click to expand...
Lambsquarter is high in P and K, and if you ferment it with molasses and water, it might be most of what you need, if you have a good low EC background nutrients like worm castings.

I have to say I have not tried that myself yet, so far I've still used a 50/50 (0.4 EC each) combination of Canna Coco A+B and Atami B'Cuzz flower hardener for high P/K values. However now I'm experimenting with Rock Phosphate, Vinasse and Molassis on top of an supersoil mix and water reservoir.
 
T

truck

Member
This is most likely from a P.H. swing. are you checking your P.H. when you feed? Calcium is most likely being locked out by Na or Mg. Too much K will cause similar issues. Careful using Molasses with anything with magnesium already in it. Causes a magnesium inversion which out competes Ca. IF your soil has hardened up this is the case for sure. You are dealing with P.H. and nute lock out on some level. Try flushing with just a Ca supplement that has no Magnesium at a P.H. of 6.5 or 7 depending on your feel. If Magnesium is locked out you are locking out Phosphorus as well, as on is required for the uptake of the other. Once a leaf has turned purple is won't green back up again, but you should still be good to go. Just don't over do the P-K in organic soil especially in a liquid feed, as it pisses of the microlife. Try just top dressing with your bone meal 1 teaspoon weeks 3-5 with maybe a 1/4 teaspoon of blood. Then water in with just Molasses or maybe some worm tea. but you should be solid if you soil mix is good. Try layering your buckets and keep the P-K on bottom away from the rootball and you should find a little better results instead of guessing when each strain wants its heavy P-K hit.
 
T

truck

Member
Forgot another good question.... Have you checked the P.H. and EC or PPM's of your run off? and here is more of my 2 pennies.... make sure there is no chlorine in your water. If you are going to do organics go all in. Using synthetics will only burst the organic bubble. Salts equal ultimate death in living organics. If you are using fresh CoCo each time you have to keep the P-K levels down over time. ALso if you are using Peat, it can be the cause of diving P.H. late in a bucket or in your recycled mix. As coco breaks down it releases both P-K back overtime and can also cause your soil to compact, so you may even want to up your perlite a tad or try finding some rice hulls to keep O2 levels consistent as things break down and compact over time and each watering. Calcium additives are the major need for coco to keep things rolling smooth. I suggest a 20% Ca to 3-5%Mg. Like i said before be very careful what you are mixing with molasses as it will cause chaos with P.H. and nute lock out. You may want to try using oyster shell in combo with the dolomite lime to keep Ca levels high in the soil and reduce the need for liquid Ca supplementation over time.
 
A

apeshot

Member
Thanks for the advice guys. Truck, is it worth checking pH and PPM from runoff when growing organically in soil? I don't pH water or anything I add to the plants, as I understood that the soil takes care of that for me.
 
dank.frank

dank.frank

ef.yu.se.ka.e.em
ICMag Donor
Veteran
Just get some bone meal or some high P guano...since already in flower, I'd go the guano route.

Top dress or make a tea...or go buy a jug of Budswel, yellow label. Stuff works wonders in a pinch.



dank.Frank
 
A

apeshot

Member
Thanks dank.frank, appreciate your suggestions. I can't get guano where I am locally, so I have used a fertiliser which claims to be for fruiting and flowering. And I have purchased the guano online, hopefully it'll arrive soon.
 
T

truck

Member
do you know the P.H. of your water and its hardness? it can cause all sorts of problems if its to alkaline.
 
A

apeshot

Member
Last I tested my pH it was in the high 7's. It is relatively soft water though from my understanding, and about 90ppm (@.5 conversion).

I checked the runoff from the plant and the pH was 6.8, ppms were 1300 (.5 conversion). Not sure what that says about things.
 
T

truck

Member
For organics, 1300 is pretty high unless you have layered using dry nutes in your bucket. could indicate the beginnings of lock out. I'd just keep using water for a couple heavy waterings then go back to a lighter feed. In my experience anything over 400-500ppm in a tea or feed in organics is un needed if your soil is right. The higher the PPM the less likely you have living soil. Try switching over to Fox Farm Big Bloom and or Big Bloom Guano to finish off in flower or a fert that is something like 0-2-2. You need to keep the fungi happy in late flower to keep your plant being fed P through the end for big buds. If you stop or disrupt this symbiosis you will lose production and better off using synthetics or organic acid based nutes to finish. The idea in living organics is to feed the microbes and let them do all the work feeding the plant. Top dressing and teas tend to work better in living organics, keep it low PPMs like i said and you'll see less issues over time.
 
T

truck

Member
I meant bud-swell guano as the other good one to finish in flower. I think someone else mentioned that too.
 
M

MuricanWeedwolf

Member
apeshot said:
Last I tested my pH it was in the high 7's. It is relatively soft water though from my understanding, and about 90ppm (@.5 conversion).
Click to expand...

Is this the pH of your water or your soil? If soil, how did you test this? If your water is on the basic side (high 7s) you may want to consider acidifying your water a bit. Vinegar is an easy way to do this, just don't add too much!


apeshot said:
I checked the runoff from the plant and the pH was 6.8, ppms were 1300 (.5 conversion). Not sure what that says about things.
Click to expand...

If your water is on the basic side (high 7s) then 6.8 is about right for runoff, but your soil has limits to how much it can buffer pH changes. Again, consider acidifying your water a bit (down into the 6s at least).

Also check your fertilizers to make sure you aren't over fertilizing with zinc. Some fertilizers have substantial amounts of zinc in them yet are not necessarily reported on the label. Check the WSDA fertilizer metals tests that are available on this website. Zinc will compete with Phosphorus in the uptake of the plant if their ratio is out of balance. Ideally you want a P:Zn ratio of around 200:1. Lower than that and you could get some P lockout from the excess Zn.

Good luck, keep us posted!
 
A

apeshot

Member
Thanks for the help guys. This was my first attempt at organics and hasn't quite gone as planned but it's a learning experience. Luckily it is a relatively small, personal grow. And I will still get some decent product, just not as good as what it could have been.

I am going to mix up a new batch of soil, which will be quite different to what I am using now. I'll use dank.frank's recipe but will have to substitute a few things as I can't get them where I am (eg: alfalfa meal, azomite, oyster shell flour). I'll create a separate thread for advice on that.
 
M

MuricanWeedwolf

Member
apeshot said:
Thanks for the help guys. This was my first attempt at organics and hasn't quite gone as planned but it's a learning experience. Luckily it is a relatively small, personal grow. And I will still get some decent product, just not as good as what it could have been.

I am going to mix up a new batch of soil, which will be quite different to what I am using now. I'll use dank.frank's recipe but will have to substitute a few things as I can't get them where I am (eg: alfalfa meal, azomite, oyster shell flour). I'll create a separate thread for advice on that.
Click to expand...

alfalfa meal - since your grow is so small, why not grow some in your backyard or in some big containers, cut and dry, pulverize

azomite - greensand is a substitute that is probably available in your area. Also kelp meal/liquid kelp is a good source of micronutrients.

oyster flower - just use agricultural lime, it's available everywhere
 
A

apeshot

Member
MuricanWeedwolf said:
alfalfa meal - since your grow is so small, why not grow some in your backyard or in some big containers, cut and dry, pulverize

azomite - greensand is a substitute that is probably available in your area. Also kelp meal/liquid kelp is a good source of micronutrients.

oyster flower - just use agricultural lime, it's available everywhere
Click to expand...

Good suggestions. I've thought about growing the alfalfa and might do that down the track, but for the moment I've got some flaxseed meal which I'm going to substitute the alfalfa for.

I can't get greensand or azomite, but got some rock dust which seems to have similar properties to azomite.

And I did get some agricultural lime to substitute for the oyster flour, as I read it's just calcium carbonate anyway.
 
M

MuricanWeedwolf

Member
apeshot said:
Good suggestions. I've thought about growing the alfalfa and might do that down the track, but for the moment I've got some flaxseed meal which I'm going to substitute the alfalfa for.
Click to expand...

Good ideas, just be aware that flaxseed meal (AKA linseed meal) can have 2-3 times more nitrogen than alfalfa meal, and may not provide the amino acids, micronutrients, and other beneficial compounds (e.g. triacontanol, a compound that stimulates growth and branching) that alfalfa does.

Good luck!
 
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