Spot Nitrogen Deficiency with Marijuana and Recover in a Week!

 Yellow leaves, stunted growth.


These can be signs of a nitrogen deficiency with your marijuana plants.

If not corrected soon enough it can spread quickly and will affect the health of your plant in a major way.


But not to worry it’s an easy fix you just need to dial in the nutes(nutrients).

First, let's take a look at nitrogen to learn why it is so important for marijuana.

Time for a little science.

Nitrogen molecule

Nitrogen is an essential nutrient cannabis needs.

It helps with photosynthesis, transporting amino acids, and increases the plant's immunity.

Without it, there is no plant growth. 

The other essential nutrients are phosphorus and potassium.

N-P-K values appear on the labels of nutrients you purchase, with different amounts for the stages of growth.

N stands for Nitrogen

P stands for phosphorus

K stands for potassium.

The way nitrogen deficiency starts is it begins from the bottom of the plant and works its way up through the stems and branches. According to Penn State University.

You may have noticed some of the lower leaves a pale green to yellow color.

This is a sign of a lack of nitrogen with your marijuana plants.

With not enough nitrogen, it affects the oldest leaves first by removing the chlorophyll from the leaf.

To provide for the upper leaves, so the plant continues to grow.

Ninety percent of the time nitrogen is an issue in the vegetative stage

Click on Image to Enlarge



Vegetative Stage

When you are growing in the vegetative stage, it's best to look for nutrients that have a higher Nitrogen level and a lower Phosphorus and potassium level.

You may have noticed this on nutrients for vegetative growth.

Nitrogen is essential for early plant growth.

Flowering Stage

When you move on to the flowering stage, your cannabis plants will require less nitrogen and more phosphorus.

The phosphorus helps with the blooming of the flowers on your herb.

During the last weeks of flowering, the marijuana plant will start to gain yellow leaves.

This is natural and do not be too concerned at this stage of the game.

You can also have nitrogen deficiency during flowering at the beginning, just add additional nitrogen to your plants if you start to see weak growth and other signs such as yellow bottom leaves.

If you notice too much nitrogen during flowering, flush your plant with water and introduce a pk booster and lower the nitrogen levels by switching to blooming nutrients.

Signs of Nitrogen Deficiency

  • Leaves start turning pale green
  • Red stems
  • Yellowing of the lower leaves
  • Browning of leaves
  • Yellowing of the veins of a marijuana leaf
  • Leaves drooping
  • Looks like over watering 
  • Wilting Leaves break off
  • Slow growth rate during vegetative stage
drooping-marijuana-plant leaves



How to Fix Nitrogen Deficiency

The easiest ways to fix your nitrogen depleted plants is to do the following:

Start using a nitrogen-rich nutrient for your veg cycle if not already.

Add extra nitrogen rich supplements to your regular feeding schedule.

Add additional vegetative fertilizer in small increments

Your marijuana plants should recover within a week after providing more nitrogen to your plants, but the yellow leaves will not recover unfortunately and will have to be removed from the plant if you have not already done so.

 Watch this quick video for hands on view,

Natural Ways

Here are some natural ways to fix your nitrogen deficiency, just add the additive to your grow medium and or your nutrients as directed.

Composted manure is recommended for growing your marijuana plants outdoors, naturally due to the smell.

Bat guano which can be found in some organic fertilizers (one being from Fox Farms called Big Bloom). They also have straight up guano is 4 lb bags by Happy Frog.

Dr. Earth Fish Meal that is rich in nitrogen can be added to both growing outdoors and indoors as well to help boost those nitrogen levels. With 9-4-1 values.

Fish Emu​l​sion is a liquid fertilizer addition that can be added when watering. It's usually a 5-1-1 mix for getting those plants to perk right up.

Organic Nutrients

There are many organic nutrients on the market that are available online or at your local grow shop.

Theses are a must for any grower and should be included in your grow.

Here are just a small few that can help you grow some nice healthy plants.

Medi One by My green planet has been approved by Doctor Hornby and has a 4-3-3 value. It’s 100 percent pure organic and is a perfect balance from vegetative all the way to bloom. All you need to do is adjust your PH levels, and it’s ready to go.

Grow Big from Fox Farms is another great nutrient for your veg phase it has a 6-4-4 value. It’s a Organic and is ideal for all types of growing. It works well with Big Bloom during the first stages of growth. With additional Bat guano.

Botanicare Pure Blend Pro Grow is a little lower on the nitrogen at 3-2-4 and organic blend that inhibits lush vegetative growth. It works well with all types of growing.

Signs of Excessive Nitrogen

  • Leaves curling downwards (nitrogen claw)
  • Dark green leaves
  • Brittle stalks and stems
  • Weak Immune system
  • Easy prey for Insects


There is always a downside of providing too much nitrogen to your cannabis plants is turning the leaves a dark green.

It affects the stalks and stems of the plant making them brittle and-and the immunity of the plant is jeopardized as well, allowing for diseases or an insect invasion.

Just lower how much nutrients you are currently feeding the plants.

You can also flush your plants with water and start with a lower nutrient cycle if you feel it’s necessary.

It’s all a matter of finding the proper balance for the different stages of growth.

If you start to notice the symptoms of nitrogen deficiency with your marijuana plants, always act fast and you should recover within a week.

Some strains of cannabis need more nitrogen than others, just the same and some are sensitive to nitrogen and need less.

The same goes for other beneficial nutrients.

It’s a matter of trial an error when growing, especially with new strains.

But once you dial it in you and your plants will be happy.

Let me now in the comments what worked for you or if this helped you recover.

Grow on my friends.

11 thoughts on “Spot Nitrogen Deficiency with Marijuana and Recover in a Week!”

  1. I’m panicking because it’s my very first plant and I was pretty much watching it die right before my eyes. So gonna follow your instructions and see. Wish me luck
    Thanks so very much

  2. What do you feel about rabbit manure to raise nitrogen? I’ve been giving straight filtered tap that sits out for 24 hours water ph around 6.5 to a supersoil mix I bought online. They’ve been going for 6 weeks in veg and started showing yellow down on the bottom I had them in 3 gallon smart pots and moved them to 5 gallon thinking I’d refresh the soil though they’re still yellowing. My buddy brought rabbit manure over and said it has a slow release N 2.4 P 1.4 K 0.6 saying this will fix it. He grows tomatoes and uses it in his garden I’m just hesitant but also at the moment cash strapped till Friday so was thinking about top dressing and watering in would love your comment on this.

  3. I’ve had two plants turn yellow overnight in Week 7 now. I’m talking 85% of the plant turning bright yellow with some larger fans coming loose & falling off. I know nitrogen deficiency is common, but how the HECK does it happen so suddenly? How can a plant go from green & healthy to completely yellow in a 24-hour period? TWICE!!!

    The first time it happened, I was growing in a Solo cup & had just fed some concentrated banana tea. I was just sure that was the cause: rootbound & a pH problem or over-fertilizing. But now my 2nd plant in a 3-gallon fabric pot has done the same exact thing at the same time! It’s actually worse this time around–I was able to reverse most of it in the Solo cup by applying diluted urine & grass tea. The color returned to most of the yellow leaves last time. Not so with this plant.

    I don’t have the funds to buy nutrients right now so I’m just trying to hang on until harvest. Any common household items/ingredients that contain fast-acting nitrogen? I’m at a loss here.

  4. Hi my bottom leaves are turning yellow my plants are still very young,
    is it nutrients? im giving water and food as store told me, with right ph level.

    What to do?

  5. Thanks so much for the info. One of my plants has bad nitrogen deficiency not sure if phosphorus too cause stems are purple (almost all) . this happened over a 2 week period because I transplanted into a 4 gallon and watered without nutrients and the pot has now taken 2 weeks to dry out so I can water again with nutrients and in the while its growth came to a halt. If I feed now you say it will take about a week I really hope so. I was not going to water with nutrients as I have destroyed many a plant by over watering and I learned to wait it out even if the plant needs food. I just foliage fed but it didn’t seem to prevent this starvation. I guess I did the best out of that situation?

  6. Quick question for everyone in this we have been growing for maybe two months 3 months now and are completely new to this we have just figured out that our plans have been nitrogen deficient my question is if we have replanted them in Fox farm soil from using miracle grow which in hindsight was a bad idea now that I know do still need to add more nitrogen

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