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If you’re growing marijuana, the trip is not always going to be easy. Like growing any other type of plant, cannabis plants can suffer problems along the way, preventing them from growing properly.
A common issue when growing cannabis plants is that they suffer a nitrogen deficiency.
This can be a particularly harmful problem, because nitrogen is needed for plants to grow properly, and if it’s got a deficiency then you’re going to notice your plant losing lots of leaves.
Fixing the problem all begins with using good soil, which will be rich in nitrogen.
But what else should you do if your cannabis plants are nitrogen deficient?
We’ve got the answers! In our useful guide below, you’ll find information on cannabis plants suffering nitrogen deficiency, an explanation of why nitrogen is important, and a variety of ways that you can help solve the nitrogen problem. Read on!
Why Is Nitrogen Important For Cannabis Plants?
To begin with, it’s worth outlining why nitrogen is important for cannabis plants (and all plants!) in the first place.
It all begins with chlorophyll. Chlorophyll is a pigment that all plants use to help them use the sun for development and growth, making it an essential part of any planet’s life.
In addition to that, though, nitrogen is used by plants to help them produce the needed amino acids and protoplasms – which are essential to the building of plant proteins and tissue.
Nitrogen In The Vegetative Stage
Nitrogen is most needed during the cannabis plant’s vegetative stage, which is when the plant is growing.
If the cannabis plant isn’t getting the right amount of nitrogen it needs, then its development and growth will slow down, and the plant won’t be able to grow as well as it can. Worse, it could lose all its leaves and fail completely.
As a result, it’s important that you spot the signs of nitrogen deficiency at this stage, and fix them with our advice from later in this article.
Nitrogen In The Flowering Stage
However, that isn’t to say that nitrogen is needed in large amounts for all stages of the cannabis plant’s development and growth.
Specifically, when it comes to the flowering stage then you can expect the cannabis plant to have a mild deficiency of nitrogen, which is normal.
This is because cannabis needs less nitrogen as it is forming the buds, because too much nitrogen can affect the harvest for the worse.
With that being said, you don’t want the nitrogen levels to be really low instead, because the nitrogen is still needed and a lack of it will impact your plant’s growth.
How To Spot Nitrogen Deficiency In Your Cannabis Plant
If your cannabis plant is suffering a nitrogen deficiency, then the first signs you will spot are on the tips of its leaves, where you will notice it losing color and turning yellow.
You should be able to see small yellow spots between the leaf veins, and the presence of yellow will mean that the plan’s growth is going too slow.
Unfortunately, the loss of color will get worse if the deficiency continues, the yellow spreading until the entire leaf goes pale.
After that, the leaves of your cannabis plant will begin to wrinkle and turn brown, getting worse until they fall off the plant completely.
This loss of color and wrinkling will begin with the oldest leaves of the cannabis plant, which also happen to be the lowest ones.
Thankfully, this gives you some time to solve the problem, before the decoloring spreads to the newer, higher leaves.
If you notice leaves turning yellow and falling off your cannabis plant just as it’s reaching time to harvest, then this should be normal.
In order to make the plant’s buds as potent as they can, the plant will consume as much as it can, and this can cause the leaves to go this way.
Besides the general threat of your cannabis plant’s leaves falling off (before harvest) the presence of a nitrogen deficiency will also cause your plant to stop developing, with its growth being halted.
However, this doesn’t just mean that your plant isn’t going to grow properly, but it also makes it vulnerable to outside threats like cold temperatures and diseases.
On top of that, it’s also not going to be able to protect itself from pests and insects.
How Can You Fix Your Cannabis Plant’s Nitrogen Deficiency?
As you’ve seen, a nitrogen deficiency can really harm your cannabis plant, stopping its growth. Thankfully, though, it’s quite easy to fix, as long as you fix it in time.
There are a variety of different ways that you can fix it, with some of them harder than others.
Is Nitrogen Deficiency Really The Issue?
However, before we get to these solutions, make sure to inspect your plant thoroughly.
If it’s the newer, highest leaves that are growing yellow, then it doesn’t mean that your plant is suffering a nitrogen deficiency, rather a deficiency of another nutrient – or a different problem altogether.
Alternatively, you might already be taking steps to increase the nitrogen content of your soil. For example, you might be using a fertilizer that increases the amount of nutrients, yet it still isn’t working.
In these cases, the problem is likely to be that your irrigation water or your substrate have a pH variation that doesn’t work for your soil.
In order to know that your soil and irrigation water does not have the wrong pH level, you’re going to need to test it. You can do this with a variety of different methods, such as pH test strips.
Alternatively, you can also buy digital pH soil testers that you insert into the soil and they give you a reading of the pH level.
You’ll want to have a pH level between 5.8 and 6.8, which is just a little under neutral and on the more acidic side. A typical cause for pH issues will be nutrient burn, which is where over-fertilization has damaged the plant.
Using A Growth Fertilizer
The easiest and best way to fix a nitrogen deficiency with your cannabis plants is by using a growth fertilizer. These are readily available and you should be able to buy them at any plant nursery.
You can buy two types of growth fertilizer: organic and mineral. An organic growth fertilizer gives your soil the added nutrients it needs, while a mineral fertilizer will give you a quicker and more accurate job.
It achieves this by containing specific chemical elements that will be absorbed more quickly.
Whichever you pick, the growth fertilizer should be both water soluble (allowing the roots to absorb it) and high in nitrogen.
Use Blood Meal Fertilizer
Another type of fertilizer that you can use to help eliminate a nitrogen deficiency in your cannabis plants is blood meal. True to its name, this uses animal blood as a source for its nitrogen.
With that being said, blood meal is a risky fertilizer to use, since it can make your soil too acidic. As a result, it should only be used by experienced fertilizers.
Speaking of acidic soil, it’s important that you are aware of your soil’s pH levels when using blood meal.
Before you apply, use soil strips or a pH tester to find the pH level of the soil, then keep testing it after you’ve applied the blood meal.
On top of this, you’re going to want to mix the blood meal with some water, because otherwise the soil may not cope. How do you do this? Read on!
How To Add Blood Meal
To begin with, you’re going to want to mix the blood meal with some water. Get a bottle and fill about 10% of it with blood meal fertilizer, before filling the remaining 90% with standing water.
Mix the two up, then leave them still for a while. As it’s waiting, occasionally re-mix it.
While doing this, you’ll need to remove the bottle lid, otherwise new gasses will be trapped inside it. Once it’s been mixed and left a few times, leave it along for a couple days.
Once you can see that there are no solids inside, you’ll notice that the level of the mixture has gone down. Mix it with standing water again, allowing for 10% solution for every 90% of water.
Now you’ve got your mix! Take your bottle and go to your cannabis plant. Very carefully remove the top few inches of your soil (not damaging the roots) and pour a small amount of your mixture into it.
In general, for every twenty square feet of soil you have, you’ll need to add a cup’s worth of the mixture.
Blood meal will be able to feed your cannabis plant the nitrogen it needs for anywhere between 6 and 8 weeks, with the fertilizer breaking down very slowly.
However, it’s a good idea to water with blood meal on a weekly basis, being sure not to overdo it.
Using Worm Castings Fertilizer
Another type of fertilizer that you can use is worm castings, which is a great choice for those who have never fertilized before.
Worm castings are very reliable, especially for cannabis plants, because they provide many of the key nutrients necessary. They’re made from the droppings of earthworms.
It’s easy to apply worm castings to the soil, too. However, if you’re not noticing results and your cannabis plant is still yellowing, then you can make some worm tea for the plants instead.
In order to make the tea, first get some buckets and fill them with water. After that, leave them open and exposed for a full day, allowing it to become cleaner.
Once you’ve done that, get something made out of porous fabric, such as an old top or sock.
Now you want to add tablespoons of worm castings inside the material. The amount all depends on how many liters you have, with 3 or 4 tablespoons of castings for every liter of water.
Tie up the fabric after this, then let it stand in the open bucket of water for about 3 days.
After that time, you’ll notice that the water will have turned dark brown – this is your worm tea! Use the tea to water your plants.
Using Your Urine
It’s not the nicest idea, we know, but your urine can be a great fertilizer for your cannabis plant – if it’s in the right conditions.
Everyone’s urine has nitrates that will help to provide your plant with nitrogen, eliminating the nitrogen deficiency.
If you’re using your urine with soil that’s in a container with good drainage, you’ll want to water the urine down. Additionally, if you’ve got irrigation water then it will need to be exposed for 24 hours so that it’s clean.
In order to water down your urine, first use a plastic container to hold the urine, before adding 10 times more water. For example, if you have half a liter of urine, then you’re going to need to add 5 liters of water.
After that, go to your cannabis plant and gently remove a tiny layer of the soil, ensuring you don’t damage its roots. Removing the soil will help to prevent any bad smells building up.
Then get your diluted container of urine and pour it into the soil carefully. Once you’ve done that, place the layer of soil back on, then water it all with regular water so that minerals won’t build up.
You should repeat this process as much as your cannabis plant needs. If it’s thriving, it needs less, but a pale and drooping plant will need more. In general, you’ll want to do it once or twice per week.
What If You’re Using Hydroponics?
Hydroponics is a process of growing plants without soil, instead using mineral nutrient solutions that are water-based.
If this is the method that you’re using to grow your cannabis plants, then it’s not going to be so easy to use your urine as a fertilizer. As a result, we’d recommend using another fertilizer.
If you want to attempt your urine, though, you’ll want to try applying around a cup of urine for every 3 gallons of reservoir water that’s present.
Nitrogen deficiency can be a big problem for cannabis plants, but if you identify it early and use our guide’s fertilizer fixes, it should be solved.
Whichever methods you try, you should see the plant and its leaves becoming much healthier after a short while.
I’m an avid gardener and cannabis enthusiast. You can usually find me in my garden caring for my plants or at my computer crafting helpful blogs for my readers.