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Nitrogen Deficiency In Marijuana Plants

Nitrogen Deficiency In Marijuana Plants

Nitrogen Deficiency:

A limited amount of nitrogen is a one of the more prevalent nutrient deficiencies amongst marijuana plants. Nitrogen is definitely a very essential nutrient for marijuana.

This is element is specifically in charge of creating chlorophyll and amino acids, which is necessary for the photosynthesis process.

Your plants tissue is comprised mostly of nitrogen, so with that being known the growth of your plant will cease quickly if there is ever a deficiency.

The deficiency begins in the lower leaves when they start turning pale green. Then the leaves will become yellow and begin dying off as the leftover nitrogen moves to help the newer growth. Nitrogen is able to travel throughout the plant as necessary.

The deficiency will move upward and the only part of that plant that will look green is the newer growth on the top half. The lower leaves will become yellow and wither. When a leaf is dying, it begins at the tips and moves towards the inside.

Signs of a nitrogen deficiency

If the lower leaves are becoming yellow during the vegetative phase or early on in the flowering phase, your marijuana plant may have a nitrogen deficiency that needs to be dealt with.

Losing a couple of leaves from the base of your plant from time to time is common, and more so with large plants. Now, if the plant is losing a large portion of yellow leaves, and the yellowing is traveling upward fast, you have a serious issue here.

Sings of nitrogen deficiency weed

Sings of nitrogen deficiency

The amount of nitrogen in comparison to other nutrients plays a big role in the growth and producing buds. The plant may display signs by the leaves getting little, less growth, and the plants appear to not be thriving. The petioles and stems will be a somewhat red or purple shade.

Too much nitrogen gives you plant a thick, dark green look, but this leaves it more defenseless to diseases and bugs. Another thing is the stalks begin to be deprived of elasticity and fragile.

It is good to know that it is common for the leaves of marijuana plants to turn yellow around the end of the flowering stage when the plant is lacking nitrogen because it is producing buds.

Tip: make sure to download my free Grow Bible for more information about how to fix Nitrogen Deficiency

Now, if you notice your plant is losing lower leave quickly because of the yellowing, particularly during the vegetation stage, you have an issue on your hands that requires and immediate solution.

For the vegetative state, your plant requires a more nitrogen and just about any plant food will do the trick. The majority of the total plant foods offered at your local garden center has a large amount of nitrogen, which is great for the vegetative phase.

Nitrogen deficiency vegetative state

Nitrogen deficiency vegetative state

The flowering phase requires lower levels of nitrogen. It is very necessary to get a nutrient system that has lower levels of nitrogen for the duration of the plants life cycle.

It’s common for marijuana plants to display signs of nitrogen deficiency when the plant is approaching harvest time. This is a positive sign for your plant. An excess of nitrogen stops budding and lessens the entire taste and scent of your plant. This is the reason every “bloom” and flowering nutrient systems mostly have a low amount of nitrogen.

nitrogen deficiency harvest

Nitrogen deficiency right before harvest time

Don’t worry if you notice your plant is displaying signs of nitrogen deficiency later in the flowering phase. Low amounts of nitrogen is actually a good thing during the later phase of the flowering stage to encourage good bud production and will enhance your yields.

Not sure if your plants have a nitrogen deficiency? Read the article Nutrient deficiencies in marijuana plants for a list with pictures of all deficiencies.

How to fix a nitrogen deficiency

The best way to resolve a nitrogen deficiency is to use a water-soluble nitrogen such as Grow Booster so it goes straight to the roots. After fertilization, all nitrogen-deficient plants will absorb as much nitrogen as possible and the plant will go back to its bright green color.

Grow booster to fix a nitrogen deficiency

Grow booster to fix a nitrogen deficiency

Here are some more things you can try:

  • Calcium nitrate (CaNO3) as a foliar fertilizer
  • Urine
  • Fish meal
  • Fish emulsion
  • Manure
  • Cottonseed meals
  • Alfalfa
  • Feather meal

There are several pre-mixed nutrients you can find in the store that have nitrogen or even try using a nitrate of soda or organic fertilizer which are great ways to give your plant nitrogen. I always buy grow supplies at this online gow shop

List of marijuana plant sypmtoms

Leaf Color: 
- Pale Color Leaves
- Yellow Leaves
- Yellowing Between Veins

Leaf Symptoms: 
- Lower Leaves and Older Growth Are Damaged
- Yellowing Between Veins
- Old Leaves Falling Off
- Withering / Sagging

Plant Symptoms: 
- Old Leaves Falling Off

So, keep in mind that if you have already given your plants nutrients, then most likely there is not nitrogen deficiency. If there is evidence of the deficiency spreading after one or two weeks of giving it nitrogen, then you need to determine what is creating the yellowing. If it is close to harvest time, then don’t worry about yellowing because this is normal.

Nitrogen Deficiency leafs

Nitrogen Deficiency leafs explenation

Closely monitor your plants and check for any issues so you are never caught off guard by a bad nitrogen deficiency. If you discover a problem and after proper treatment, your plants will heal in about 7 days are so, with an exception of the leaves that were harmed the most.

Remember that plants with strong genetics have less change of getting sick. Make sure you buy marijuana seeds from a trusted seedbank.

Thanks for reading. Please leave comments or questions below and don't forget to download my free grow bible


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Comment Section

43 thoughts on “Nitrogen Deficiency In Marijuana Plants

By megan on 22 January 2015

Do u have any samples?

By Kyle Sacker on 24 June 2015

Clean your room with Grow Clean!!

By dutch on 18 July 2015

My best plant went from healthy to barely alive in four days! I thought it was a nitrogen def so I started treatment on day one. No matter how much nitrogen I gave it wouldn't heal her & I tried organic blood meal, urine, & miracle grow. The only thing I can think of is after three weeks of rain it washed all the nitrogen out of the soil & when I did nitrogen her up it was locked out. After a flush of nothing but gallons of rain water I retried to solve the problem with no luck!!!! :'( RIP Medusa

By latewood on 21 July 2015

If and when you ever have to flush your entire medium; Or, as in this case, rain washed out your minerals, you should re-pot with fresh soil. Arbitrarily dumping all kinds of different Nitrogen elements to the mix is going to create an imbalance. It is possible that the only issue was the plant got over watered during all that rain. :).

By Jasper on 10 December 2015

I have a bit of a problem with my girls. They are 7 weeks and were doing great till the bottom leaves started to turn yellow,I started using a fish emulsion fertilizer 5-1-1 non burning and is seemed to help alittle at first but then continued to worsen. I have now switched to a 24-8-16 and I started this 1 week ago today and gave them another dose tonight. I know I have a nitrogen problem but I need to know if I should give them more due to the leaves are not up to par. Any idea's?

By Andre on 23 December 2016

You should flush that lady

By Roomey boy on 11 June 2018

Which is it though?

By latewood.ILGM on 12 December 2015

The leaves that are damaged are never going to look good again.. The best thing to do is monitor the new growth, to see if it is healthy.

Changing from one odd fertilizer to another is not going to help. There is no way you should have a Nitrogen deficiency with the fertilizers you have been using.

Good Luck. 🙂

By eagles on 19 December 2015

when repotting would it be best to have fertilizers mixed into the soil rather than to start pumping nutes after the transplant

By latewood.ILGM on 22 December 2015

Fertilizer mixed into soil generally needs to be replenished at some point. This is more a matter of growers choice and grow methods.

Age of the plant also comes into play, especially if plant is really young.

By Jprez on 10 June 2016

Alright here is the thing I started growing a plant I water every now and again there was this time I didn't water it for weeks then when I went to go check on it and the bottom leaves were yellow and the one top one was green so do I have a nitrogen deficiency

By latewood.ILGM on 12 June 2016


I believe you have a grower deficiency. Plant needs to be on a consistent schedule throughout their entire grow cycle. Growing part time will not yield you very much for the effort.

I advise you to join our support forum. We have many knowledgeable members and experts always willing to help. 🙂

By dickiefickle on 7 July 2016

picture with caption Nitrogen Toxicity , but when clicked it talks about Nitrogen deficiency

By Neil scaife on 20 July 2016

I bought some ak47 seeds and they are growing good I hope,my only question is I have ordered the grow bible but never comes to my email (why)

By Roy ILGM on 20 July 2016

Hey Neil, there was some trouble with the mailserver but you should've received it by now. Enjoy!

By Sheila on 14 July 2017

May be a dumb question to you, but did you down load ? My download took almost 2 hours to completely show up on my computer. May be this may help, if not , just trying to help

By W on 2 August 2016

Hi I believe I have a nitrogen defiencey in (2weeks) flower is this too much or to less nitrogen which I causing my yellow weak leaves failing off? Does anyone know of a solubable solution ? Is it too much. Nitrogen or too less?

By latewood.ILGM on 4 August 2016


In the 2nd week of flower and depending on your nutrient system; Leaves may yellow and ide off due to being used up by the plant.

I suggest you download and read our free grow bible.

I also strongly suggest you join our free grow support forum where we have many friendly and informative members willing to help. I will help you too; "Post my name in the titile" 😉

By Keith Murdock on 16 August 2016

I had a slight nutrient burn on the tips of the leaves followed up by some mites I thought I had resolved all of the issues and about 5 days ago the yellowing you described almost exactly in nitrogen deficiency hit about a dozen of my plants my question is will a nitrogen boost be complicated by my recent nutrient burn.

By latewood.ILGM on 18 August 2016


You mention nutrient burn, and spider mites, and yellow leaves...Not sure where you are going with this. The blog is not as good as our support forum for assisting growers to overcome their grow related issues. !latewood when you get there.

By Pat Lyn on 10 September 2016

My girls are 6 weeks into flower and the budding is going great. My concern is a very rapid yellowing of the lower leaves and on one plant they are turning as they go up the middle of the main stem. I think they loosing faster than gaining, I'm trying to decide if a little nitrogen would help or hurt. Suggestions?

By KidGreenThumb on 11 September 2016

@Pat Lyn; this is totally normal in the later stages of flower as your plant begins to utilize the remaining nutes from its leaves. Your are getting close to harvest time and should check the trichomes using a microscope, when they turn milky to amber in color, chop away..

By Douglas Allen on 30 January 2017

Just started my first plants but stock is very week just got their first leaves is this a sign of not enough nitrogen have them supported up with Bobby pins lol

By latewood_ILGM on 1 February 2017


Seedlings do not need Nitrogen until they have 4-5 true sets of leaves. I strongly advise you to read our free grow bible, and to join our support forum. We have many helpful members and expert alike that would help you learn to grow successfully, and you have a lot to learn my friend. See you there 😀
sign up!

By Joe Green on 24 October 2017

Wow, talk about an article that sends you off on a terrible path! lol. Not one of those images is a nitrogen deficiency!!! Then on one you put 'nitrogen deficiency before harvest'??? LOL..plants don't use nitrogen just before harvest anymore! your research people..this article is completely wrong in every sense! 1st image is either a sulphur or iron def, the next is a potassium def, and the one before harvest is normal. Who writes these fake articles? lol

By latewood_ILGM on 30 October 2017


You are just so full of yourself. actually; It is a Nitrogen deficiency. We know this because we starved the plant of Nitrogen in order to create the issue for the article.

2ndly, The plant will uptake Nitrogen as long as you provide it. Seems it is you that really should do some more research.

Good day, Sir.

By CBDiva on 29 May 2018

Thank you for including "urine" in your list of nitrogen solutions. People need to get over their aversion to this because it's an excellent (and free) organic fertilizer. I dilute mine at a 12:1 ratio & it perks my plant right up. The NPK ratio is about 11-1-2 on average.

I've suddenly encountered a rapid, severe nitrogen deficiency in Week 7 (from seed) after applying some banana tea fertilizer. Don't know how it turned my leaves yellow & crispy virtually overnight, but it did. The buds look great but now I've got to deal with a massive nitrogen problem. Hoping to halt it before it kills my whole plant. I don't have many leaves to spare on this short autoflower!

By Fred Pen on 15 June 2018

How much N should you feed and how often? 1/16th of a pound of actual Nitrogen per plant every 2 weeks ???
Is urea the best source?

By latewood_ILGM on 19 June 2018


There is no magic amount of fertilizer (nitrogen) to add. First of all, it depends on the size of your grow. If you are taking a measured asmount of Nitrogen and adding it to an acre; You would have one value. If you are addibng Nitrogen to one plant; That would be a vastly different value.

I suggest you buy a trusted powder formula, and follow directions mixing it into 5 gallons or whatever reservoir size you prefer, and you will be happy. We sell an awesome powdered nutrients system. Easiest nutrients I have ever used. Or; Many brands on the market sell powder. Happy growing.

Most people consider urine an emergency nutrient, but some growers actually use it all the time.

As I always say; This is a matter of personal choice. What do you want to do? 🙂

By Anna on 27 August 2018

I have plenty of good horse manure, how can I add it to my plants growing outside in pots in southern Spain. Thank you.

By latewood_ILGM on 28 August 2018


You should mix up manure with soil and other amendments prior to adding to a pot. Another thing to know is that the manure needs to be cured for 6-12 months before adding it to your soil

Manure os too hot to be used immediately, and can burn up the root zone if not properly cured. If you add a little to soil, you might be able to try it on one plant and see how it does.

Happy growing.

p.s. I suggest you find a composting book to help guide you.

By curt on 11 September 2018

my plants are flowering and on week 4. for about the last 3 weeks the growth has slowed and the leaves are droopy, very dark green, and some have a glossy, waxy look on the top surface. I haven't fertilized for three weeks suspecting a nitrogen toxicity. please advise.

By latewood_ILGM on 12 September 2018


I advise you to go to: and allow us to help you. We are not set up here to have continued discussions and I have a feeling this will be more of a Q and A, than a one answer deal. See you there 🙂

By CBDiva on 31 October 2018

My entire plant keeps going yellow on Week 7! Both are autoflowers; one grown in a Solo cup & the other in a 3-gallon fabric pot. I thought the first one did that because it was confined to the small cup but apparently not. The only thing I did differently was add a 20-watt LED light over the weekend...could that have increased the plant's need for nitrogen or something? I'm growing in soil w/ CFL bulbs (84 watts total). No bottled nutes, just things like diluted urine, potassium humates & grass tea. Works great until Week 7 apparently.

I'm talking overnight 85% of the plant's leaves went from green to bright yellow...only the inner bud sites are still green. One of the fans fell off as well. I am shocked this has happened a second time in the larger container. I didn't feed or water them for at least 2 days leading up to the change. Been checking my pH more often than not. These are two entirely different strains of cannabis too. Harvest isn't supposed to happen until Week 10 or 11.

Why would a plant suddenly starve for nitrogen in flowering in a matter of hours? Do you think it's the weak LED light I'm adding at that time or just a coincidence? I assumed nitrogen deficiency was more gradual than this.

By latewood_ILGM on 4 November 2018


You really should join our support forum. I think you would enjoy the friendly sharing atmoshere and learn a bunch. 🙂

Well, yellowing that fast can be because the plant media got too dry, and the leaves gave up their moisutre to keep plant alive.

The lack of light intensity could also be playing a part as the extremely small amount of lumens you are supplying the plant may not be intense enough for the plants to actually take up the nutrients.

3rd. You have a lot of minerals necessary to grow properly...missing.

Like I said, join our forum where we are set up for Q and A, and better suited to help you make an informed decision. Peace 🙂

By william lebron on 14 November 2018

Hello Robert, I was wondering if you still happened to carry the flower power start, bloom and grow and the thc boost for $39.00 if so please email me back with an address.

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