If you’ve ever grown weed, the chances are that you’ve faced a level of nitrogen deficiency in cannabis. This common issue often goes unnoticed as its symptoms mimic many of the natural aging processes we’ve come to expect in plants.

Learning how to identify and solve cannabis deficiencies early will set you up for future success. Today, we explain the importance of nitrogen in cannabis and how to spot a lack of this vital nutrient in your crop.

You’ll also learn how to treat a nitrogen deficiency in weed, allowing you to reap bigger yields and better buds. Let’s get started!


What does Nitrogen do for Cannabis Plants?

You could say that marijuana and nitrogen go hand in hand—this nutrient is a crucial component of any living organism, including you. It serves as a necessary building block responsible for growth and vitality.

Nitrogen in cannabis is responsible for one of the most important phenomena in plants, known as photosynthesis. This is the process that allows leaves to convert sunlight into the energy your marijuana needs to survive. It does this by helping to produce chlorophyll.

Chlorophyll is the green pigment present on all marijuana plants. Without this chemical, the leaves will turn yellow and stop converting energy. This is also one of the first symptoms of nitrogen deficiency in cannabis and one of the easiest ways to spot it.

Nitrogen is also one of the main ingredients in amino acids. These compounds act as the building blocks of a marijuana plant. They help to metabolize inorganic materials like water and carbon dioxide. It then turns them into proteins, effectively creating food for your plant.

Another crucial role for nitrogen in cannabis is to create nucleic acids. You may know these molecules as DNA and are responsible for carrying genetic information. Without these nucleic acids, your plant wouldn’t reproduce or grow.


How to fix a nitrogen deficiency in cannabis


Nitrogen is a Mobile Nutrient - What does this mean?

If you’re not familiar with the term, a mobile nutrient describes a compound that can move around as needed. If there’s a shortage, such as a nitrogen deficiency in cannabis, the plant takes from older parts to assist newer areas.

On the other hand, immobile nutrients, like calcium and magnesium, can’t move around. This is an important distinction to make to help you identify whether you have a cannabis nitrogen deficiency or something else.

As a rule of thumb, mobile nutrients give new leaves and growth priority. That means you’ll first identify issues like a nitrogen or potassium deficiency in weed in older sections of your plant. In comparison, a lack of immobile nutrients presents itself in young leaves.

Throughout your plant’s life cycle, it requires different amounts of this all-important mobile nutrient. Understanding when to add or take away traces of this element helps you avoid a nitrogen deficiency in cannabis.


Vegetative Stage

The vegetative or vegging stage describes the portion of your plant’s life cycle where it spends its time growing. During this phase, plants produce plenty of leaves, so their nitrogen requirements are at an all-time high.

It’s also at this stage that you’ll most likely encounter a nitrogen deficiency in weed. Losing a leaf here and there during this time is a natural occurrence and nothing to worry about. However, if the majority of your marijuana leaves turn yellow, you probably have an issue.

Lacking this crucial nute can lead to poor yields and unsavory buds at this point of the growth cycle. If you don’t remedy this issue quickly, there’s even a chance your plant will die.


Flowering Stage

Like most plants, the flowering stage is by far the most beautiful phase to behold. This is the point where it begins to bloom flowers, or in cannabis terms, juicy buds destined to enhance your mood and soothe the soul.

At this point, a marijuana plant’s need for this mobile nutrient decreases dramatically, but not entirely. To avoid a nitrogen deficiency in cannabis during the flowering stage, you’ll need to use nutrient systems with low amounts of this compound.

What’s more, a nitrogen deficiency in marijuana at the later stages of flowering is a good sign. An abundance of this mobile nutrient can reduce the smell and taste of your weed. It can also prevent your buds from developing properly, affecting your yield.


How do you Identify Cannabis Nitrogen Deficiency?

As you can see, this mobile nutrient is incredibly important for your weed plants. To prevent a nitrogen deficiency in cannabis, you should look out for a few tell-tale signs. These symptoms are relatively easy to pick up as long as you know where to look.

Below, we take you through the most common ways to identify marijuana nitrogen deficiency.


Yellow Leaves

The first key symptom to look out for is your weed plant’s leaves turning yellow. This process occurs naturally, where older parts begin to lose color, wilt and fall off. A plant always prioritizes growth, diverting energy to new leaves that receive the majority of sunlight.

This phenomenon is even more present as your plant enters its flowering stage. It focuses less on growth and more on the development of buds. When the majority of your marijuana leaves turn yellow, you’ll need to remedy this deficiency.

You should also notice the lower fan leaves start to curl and fall off. This is also a symptom of a phosphorus deficiency in cannabis. The way to tell the two issues apart is by the dark colors displayed for the latter.


How to fix a nitrogen deficiency in cannabis


Stunted Growth

A nitrogen deficiency in cannabis also causes stunted growth as it affects the root system. Spotting this issue is slightly more difficult for obvious reasons. The only time you can thoroughly inspect roots is when you’re moving your plants to bigger pots. 

Roots can become damaged from a marijuana nitrogen deficiency because of its effect on the soil’s pH level. Once your soil medium becomes too acidic or alkaline, your plant will struggle to absorb nutrients and grow.

A nitrogen deficiency in cannabis causes the roots to become slimy or underdeveloped, indicating a toxic pH level. If left unattended, this issue can lead to premature flowering and overall lower yields.

An easier way to spot stunted growth is when your plant remains small in stature. This can become slightly difficult if you’re only cultivating one plant, as you don’t have anything to compare it to. For the most part, your plant should show signs of new growth almost every day.


How to Solve Nitrogen Deficiency

If you’ve noticed any of these symptoms displayed in your marijuana crop, don’t panic. A nitrogen deficiency in cannabis is easily remedied. You can even completely avoid this issue by implementing a few good habits.

Below, you’ll find three of the best ways for you to solve a nitrogen deficiency in cannabis plants.


Amend Nutrients

The first way to solve a nitrogen deficiency in weed is by giving your plant additional nutrients. You’ll need to gauge the level of insufficiency by the amount of yellow on your leaves. The more discolored they are, the more nitrogen you’ll need to provide.

You can identify the percentage of nitrogen in a bottle of nutrients by the three numbers indicated on the label. These readings provide the ratio of N-P-K present in the fertilizer. The first number represents nitrogen, followed by phosphorus and potassium, respectively.

There are products with low levels of nitrogen, which are used in the flowering stage. For the most part, you need a high amount to treat a nitrogen deficiency in cannabis.

It’s also worth noting that there are different kinds of fertilizer available. Water-soluble types work quickly, allowing your plant to absorb nutrients faster. In comparison, you could use an insoluble version like bat guano that releases slower but for a longer period.

Whatever option you choose, remember that results aren’t instant. After amending your nutrients levels, you may need to wait up to a week before seeing an improvement. Refrain from adding too much fertilizer, as this causes even more problems.


Maintain Good pH Levels

A good habit to practice for any cultivator is testing the pH levels present in your soil and water. Not only will this help you avoid nitrogen deficiency in marijuana, but also other illnesses.

When it comes to your soil, you should aim for a pH balance between 5.8 and 6.8, with 6.3 being the ideal number. You won’t solve a nitrogen deficiency in cannabis if the roots can’t absorb any nutrients.

As for the water that you use to feed your plants, it should have a balanced pH of 7. Never assume the quality of your liquid food, as it can change due to many different factors. Regularly testing your water source is a great habit to adopt.


Trim Affected Leaves

The last way to solve a nitrogen deficiency in cannabis is by removing the affected leaves, stopping the spread. Trimming the lower fan leaves turning yellow during the veg stage helps the plant direct nitrogen to its newer foliage.

Maintaining your plant’s leaves is a necessary part of growing cannabis. You’re killing two birds with one stone, cutting affected leaves off, and increasing airflow around the plant.


Nitrogen Toxicity

Treating a nitrogen deficiency in cannabis is somewhat of a balancing act. As we’ve already mentioned, there is such a thing as giving your plants an excess of nutrients. Whether it’s due to inexperience or impatience, your plant’s nitrogen levels can become toxic.

Although nitrogen toxicity rarely occurs during the plant’s vegging stage, it can become an issue once marijuana starts to flower. One way to spot this issue is when lower leaves turn a dark green color.

High levels of nitrogen in cannabis also cause the plant’s stems to weaken. You’ll notice the branches and leaves wilting.

Another symptom of nitrogen toxicity is your plant absorbing far less water than you’re used to seeing. This is a sign that your plant’s roots have become damaged, making it hard to transport fluids.


You reap what you sow

If you hope to see massive yields and potent buds, you’ll need to avoid a nitrogen deficiency in cannabis. Luckily, this insufficiency is easily remedied by monitoring your plant’s nutrient levels and physical appearance.

Remember that improvement isn’t something that happens overnight, and patience will always triumph in the end. Don’t lose faith in your crop at the first sign of weakness. Instead, consider these issues as an opportunity to learn and become a better cultivator overall.

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