Someone please this N deficiency?

:Disclaimer: This is NOT a picture of my plant, but it looks just like what is happening to mine. I can’t get a pic of mine due to the scrog screen it is entwined in.

Just noticed that several leaves on our Strawberry Kush are turning yellow. They are 3 weeks into flower.

They are in FFOF and up until the last couple of days all seemed well. If you need any more info I am going to find a ticket to fill out but thought I would put this up first. We have not been able to get a runoff ph as of yet, but ph going in has been a consistant 6.4-6.6. We are going to try for a runoff ph tomorrow night.

Anyone have any advice. I have a journal going but can’t seem to get much response there on questions I have asked in the past so I am going directly to the nutrient forum with this one, because, well I am worried. We have 2 other plants on the same schedule and they do not seem to have this problem. Different strains tho.


Strain; Strawberry Kush
Soil in pots, Hydroponic, or Coco? Soil, FFOF
System type? N/A
PH of runoff or solution in reservoir? Not available tonight will get a run off tomorrow night
What is strength of nutrient mix? EC, or TDS: FF trio at 1/2 strength for 2 weeks flowering = Big Bloom 7.5ml, Grow Big 2.5ml, Tiger Bloom 5ml.
Indoor or Outdoor: Indoor
Light system, size? :400W HPS 100%
Temps; Day, Night 75 -65
Humidity; Day, Night 50-60
Ventilation system; Yes, No, Size Yes, 190cf/minute, 4inch inline fan
AC, Humidifier, De-humidifier, no
Co2; Yes, No, no
Add anything else you feel would help us give you a most informed answer. Feel free to elaborate, but short, to the point questions and facts will help us help you.

Also wanted to add that the buds seem to have stopped growing. Anyone care to help??


Not to 2 worry my friend.
his is large but very informitive Copy it to your note book for later referance

Nitrogen (N) Mobile Element and Macro Element

Benefit: Nitrogen plays a very big role in your plants; this one element is directly responsible for production of chlorophyll, photosynthesis, Amino Acids, which are the building block of Proteins. The myriad of enzymes which help the plants growth in leaves stems and the how well the vigor of your plants is.

Nitrogen is the biggest mobile element meaning it can travel anywhere on the plant.
Usually the def will start on the lower to middle part of the plant, and then will usually happen to older leaves first. Then the deficiency will work its way up the plant. Your plant can be green on top, then yellowing on the lower leaves when the deficiency is starting out. Yield will be greatly reduced without good amounts of nitrogen in your plants. Sometimes in bad cases the leaves will turn a purplish color along with the yellowing.

Unlike a magnesium deficiency, nitrogen def will start from the tips and work its way back to the leaf node. Nitrogen and Magnesium get confused. The best way to tell them apart is, nitrogen deficiency starts around the tips and works its way to the back of the leaves, where a magnesium deficiency will cover the entire outer part of the leave and make the entire leaves yellow leaving the veins to stay green. If your plants are having a slow growth rate and have yellowing of the leaves, then most likely it’s a nitrogen deficiency.
Towards the middle to end of flowering stages, the plant will show a nitrogen deficiency almost always. This process is completely normal and just let the plant naturally yellow out as it uses it’s stored nutrients. This actually helps you by getting ready for final flushing and then harvesting. At this point DO NOT not use nitrogen to fix the problem. The yellowing leaves will then eventually drop off after the plant is done with them.

Parts affected by a nitrogen deficiency are: Older foliage, going to whole plant, Petioles (rare) cases.

Now for having too much nitrogen in your growing mediums or soil. The plant will have like an overall DARK green look and have delayed maturity. Due to Nitrogen being involved in vegetative growth, to much nitrogen will result in tall plants with weak stems. New growth will be very lively and plant transpiration will be high, but not always. Nitrogen toxicity can be seen when there are very very dry conditions almost as if there was a drought, which may show a burning effect. If you give your plants ammonium based nutrients they may show NH4+ toxicity, which will show a smaller plant growth and lesions that occur on stems and roots, leaf margins that will roll downward. Also the big fan leaves will have “the claw” look. The tips will point down but the leaves will stay up as if when you bend your fingers downwards. Leaves can be twisted when growing… mainly new growths. Roots will be under developed along with the slowing of flowering. Yields will be decreased, because to much nitrogen in early stages of flowering slows down bud growth. Water uptake is slowing down from the vascular breakdown of the plants as well. Too much potassium and nitrogen will lock out calcium as well.

Problems with Nitrogen being locked out by PH troubles.
Waterlogged soil and Soil with low organic matter.

Nitrogen is a very important element in the plant, all of them are but some are more important than others. For soil the best ph to have is 6.8. Why? Because at 6.8, that’s the best number for ALL available nutrients to be absorbed into the plant without any of them being locked out. For hydro and soil less mediums best ph to have is around 5.8.
Try not to keep your plants to cold, because the cold temps will cause the nitrogen harder for the plant to be absorbed.

PH levels for Nitrogen:

Soil levels
Nitrogen gets locked out of soil growing at ph levels of 4.0- 5.5.
Nitrogen is absorbed best in soil at a ph level of 6.0-8.0. ( wouldn’t recommend having a ph of over 7.0 in soil) best range to have nitrogen is a ph of 6-7. Anything out of that range will contribute to a nitrogen def.

Hydro and Soil less Mediums
Nitrogen gets locked out of Hydro, Soil less mediums at the levels of 4.5-5.0.
Nitrogen has the best absorption rate at a ph of 5.5 to 8.0
(Wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range to have Nitrogen is: 5.0-7.0. Anything out of that range will contribute to a nitrogen def.

Solution to fixing a Nitrogen deficiency

Avoid excessive ammonium nitrogen, which can interfere with other nutrients. Too much N delays flowering. Plants should be allowed to become N-deficient late in flowering for best flavor.
A goof solid N-P-K ratio will fix any nitrogen deficiency. Any chemical or organic fertilizers that have Nitrogen in them will fix a nitrogen deficiency., Peters all purpose plant food 20-20-20 is good, Miracle grow All purpose plant food, Miracle grow Tomato plant food, (Only mixing at ½ strength when using chemical nutrients, or it will cause nutrient burn!) as well and blood meal! If you need to give your plants a quick solution to nitrogen and you want to use blood meal, I suggest making it into a tea for faster use, where blood meal is slow acting, but when made into a tea it works quicker! Other sources of nitrogen are dried blood, Cotton seed meal which is slow acting, Insect eating bat guano which is fast acting. Bone meal which is a gradual absorption when not made into a tea.( also excellent source of phosphorus). Fish Meal Or Fish Emulsion is a good source of nitrogen and is medium acting. Worm castings, which is gradual absorption. Seabird guano, All purpose Millennia Seabird guano, Orginal Seabird guano All Purpose, Crabshell ,which is slow absorption. Fox Farm Grow Big, which is fast acting. ( can bring down your ph as well)
Here are a list of things that help fix a Nitrogen Deficiency:

Chemical Nutrients

Advanced nutrients Grow (2-1-6)
Vita Grow (4-0-0),
BC Grow(1.2-3.2-6.5)
GH Flora Grow (2-1-6)
GH Maxi grow (10-5-14)
GH floraNova grow (7-4-10),
Dyna gro Grow (7-9-5)

Organic Nutrients

Dr. Hornby’s Iguana Juice Grow (3-1-3)
Advanced Nutrients Mother Earth Grow (1.5-.75-1.5)
Earthjuice Grow (2-1-1),
Pure Blend Pro (3-1.5-4)
Bone Meal(0-10-0)
Blood Meal(12-0-0)
Fish Emulsion (5-1-1)
Seabird Guano (11-13-3)
Crab Shells(2.5-3.0-.5)
Pure Blend Grow (0.4-.01-.5)
Marine Cuisine (10-7-7)
MaxiCrop Seaweed (1-0-3)
Super Tea (5-5-1)
Mexican Bat Guano (10-2-0)
Sea Island Jamaican Bat Guano (1-10-0)
Kelp Meal (1-0-2)
Seaweed Plus Iron
Neptune’s Harvest (2-4-0.5)
Alaska Start-Up(2-1-2)
Bio-Grow (1.8-0.1-6.6)
Age old Grow (12-6-6)
AGE Old Kelp (.30-.25-.15)
Neptune’s Harvest (2-4-1)
Maxicrop Seweed(.1-0-1)
METANATURALS Organic grow (3-3-3)
METANATURALS Organic nitrogen (16-0-0)

So adding anyone of these above should fix up your nitrogen deficiency! Nitrogen deficient plants usually recover in about a week, affected leaves will not recover.

Now if you added to much chemical nutrients and or organics, (which is hard to burn your plants when using organics) you need to flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients. Soluble nitrogen (especially nitrate) is the form that’s the most quickly available to the roots, while insoluble N (like urea) first needs to be broken down by microbes in the soil before the roots can absorb it.

Note: Blood Meal, Dried Blood, Guanos, Kelp Meal, Cotton Seed Meal, Peat Moss, Sulfur and fish meal are all acidic and can bring your ph down, so if you add these please monitor your ph when using those.

Note: Bone Meal, Rock Phosphate, Wood Ashes pretty much all ashes, Shellfish Compost and Crab Meal are all alkaline and can make your ph go up, so if you add any of these please monitor your ph.

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Thanks for the info @garrigan62, awesome stuff!

This looks to be affecting one side of the plant and seems to have started towards the lower to middle part of the plant. I really do think it is N def.

The infor you posted mentioned Grow Big is a good solution, do you agree? or should I go with someone more like blood or bone meal?

I have a ppm meter that I intend on using tomorrow night as well. what ppm number should I be looking for?

I am completely lost here if you cant tell lol. thanks so much for your help!

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That’s fantastic! Thanks!

If I can still help just ask me. I will be here l promise

Have you been away for a while @garrigan62 or have I just been not paying attention. It is good to see you.


Yes…my cancer came back and I had to deal with it and still am and I may be starting keymo this week

I am really sorry to hear that, Bro…I hope that you and your doctors are able to get it back into remission. It is sad that none of us can be of any help, we can just hope for the best for you and your family.


That’s about all anybody can do.
But they the Doctors have got’n it into remission
Back in 2009 and they will this time


Excellent, keeping a positive outlook helps, I think.

Are still growing?

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Yes it dose. Always think positive even when things get bad…
Going to start up here the end of February

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I hope that you find starting back up as therapeutic as I did. Cannabis plants are a great distraction from the day to day grind.

@garrigan62 here is a link to an update on my current grow.

I will be harvesting about when you get your next grow started.

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Ya I think it will to.
And I’ll have a lot to keep me busy getting ready.
Just not sure what to grow. Maybe two of each that would give me something like 15 or 20 plants

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