Nitrogen deficiency in cannabis plants: symptoms & solutions

Nitrogen is one of the most important nutrients for cannabis plants, as it plays a significant role in growth and development. It plays a key role in the production of chlorophyll, which is required for photosynthesis, and is therefore directly responsible for the plant's energy production. Without sufficient nitrogen, the plant cannot produce enough energy to grow healthily.

A nitrogen deficiency often manifests itself in the form of yellow leaves, growth disorders and generally weakened plants. If this deficiency is not remedied quickly, it can damage the plant in the long term and significantly reduce the yield - especially in the important flowering phase.

How do you recognise nitrogen deficiency in cannabis plants?

Nitrogen deficiency in cannabis plants can often be recognised early on by the leaves and general appearance. The most common signs include

• Yellow leaves A typical symptom of nitrogen deficiency is yellowing of the older, lower leaves. This is because the plant transfers the nitrogen from these leaves to the younger leaves in order to maintain growth.

• Wachstumsstörungen As nitrogen is responsible for cell division and growth, a deficiency causes the plant to grow more slowly overall. New shoots are smaller and the plant often appears weak and puny.

• Weak stems Another indication is that the stems become less robust. They may appear thinner and weaker, making the plant more susceptible to external influences, such as buckling under the weight of the Flowers.

These symptoms worsen if the deficiency is not corrected and can ultimately have a significant impact on the harvest.

Causes of nitrogen deficiency in cannabis

Nitrogen deficiency can be caused by various factors that restrict the plant's access to this important nutrient. The most common causes include

• Insufficient nutrient intake One of the most obvious causes is an insufficient supply of nitrogenous fertiliser. Especially in the growth phase, when the plant needs nitrogen in large quantities, a deficiency can occur if the nutrient plan is not balanced.

• Incorrect pH value The pH value of the soil or nutrient solution plays a decisive role in nutrient uptake. If the pH value is outside the optimum range (between 6.0 and 7.0 in soil, 5.5 to 6.5 in hydroponics), the plant cannot absorb nitrogen effectively, even if there is enough available.

• Nährstoffsperre Nutrient blockage can occur when certain minerals accumulate in the soil or nutrient solution and block the absorption of nitrogen. This can happen if too much fertiliser is used or the nutrient composition is unbalanced.

Understanding these causes is key to preventing and quickly remedying nitrogen deficiency in cannabis plants.

What nitrogen deficiency looks like in the flowering phase

A nitrogen deficiency in the flowering phase differs significantly from a deficiency in the vegetation phase, as the plant's nutrient requirements change during the various growth stages. In the flowering phase, the plant needs less nitrogen, as the focus is on the development of the Flowers. A slight deficiency in this phase is therefore normal, but a severe deficiency can have serious consequences.

Differentiation between deficiency in the vegetation and flowering phase:

• Vegetationsphase In this growth phase, cannabis needs a lot of nitrogen to form strong, green leaves and strong stems. A deficiency quickly manifests itself in yellowing leaves and slower growth. The plant appears weak and hardly develops any further.

• Blütephase : During the flowering phase, the plant shifts its needs towards phosphorus and potassium, which are crucial for flower formation. A slight nitrogen deficiency is normal during this phase as the plant shifts its energies from leaf production to Flower. However, too severe a deficiency can hinder the growth of Flowers and the plant becomes more vulnerable overall.

Effects on Bud development:

A severe nitrogen deficiency in the flowering phase means that the plant does not have enough energy to develop its buds optimally. The Flowers remain small and the density leaves a lot to be desired. The end result can be less yield and poorer quality Flowers, as the plant uses up its reserves to keep itself alive instead of investing in flower production.

It is therefore important to reduce nitrogen in controlled quantities during the flowering phase in order to maintain a balanced nutrient balance and ensure a rich harvest.

Correcting cannabis nitrogen deficiency: step-by-step instructions

If you notice a lack of nitrogen in your cannabis plants, you should act quickly so as not to impair growth. Here is a simple step-by-step guide on how to correct the deficiency:

Confirm 1st diagnosis

• Check symptoms Yellow leaves, slow growth and weak stems indicate nitrogen deficiency.
• Focus on older leaves : Especially when the lower leaves turn yellow, this is a classic sign.

2. measure pH value

• Test the pH value of the soil or nutrient solution : Use a pH meter.
• Optimum pH range : The pH value in the soil should be between 6.0 and 7.0, for hydroponics between 5.5 and 6.5.
• Adjust pH value : Use pH-up or pH-down products to bring the value into the optimum range.

3. add nitrogen-rich fertiliser

• Select a suitable fertiliser : Use a nitrogen-rich fertiliser that is suitable for the growth phase of your plant.
• Note dosage : Start with a lower dose to avoid over-fertilisation and observe the plant over the next few days.

4. use household remedies (optional)

• Urine as a quick solution : Fresh urine in the ratio 1:10 with water mix.
• Use with care : Pour this mixture sparingly, use only in urgent cases and always highly diluted.

5. monitoring and maintenance

• Observe changes Check the plants over the next few days for improvement. The leaves should stop yellowing and growth should recover.
• Stay patient It may take a few days to a week for the first signs of recovery to appear.

6. long-term prevention

• Regular pH control : Continue to monitor the pH of the soil or nutrient solution to avoid future problems.
• Balanced nutrition plan : Keep an eye on the nitrogen balance, especially in the vegetation phase, but reduce it slightly in the flowering phase.

By following these steps, you can ensure that your plants are sufficiently supplied with nitrogen and can recover quickly.

Tips to avoid nitrogen deficiency in the future

Nitrogen deficiency can be easily prevented with good care and prevention. Here are some effective tips to ensure that your cannabis plants are always sufficiently supplied with nitrogen and grow healthily:

Use of organic fertilisers (e.g. Biobizz)

Organic fertilisers such as Biobizz are ideal for providing your plants with a continuous supply of nutrients without the risk of over-fertilisation. Biobizz products contain natural ingredients that release nitrogen slowly and evenly, which helps plants to make optimum use of this important nutrient throughout the growth phase. Organic fertilisers also promote soil life and improve soil structure, which leads to better nutrient uptake.

Regular monitoring of the pH value

A stable pH-Wert is crucial for the absorption of nitrogen and other nutrients. If the pH is outside the ideal range (6.0 to 7.0 in soil, 5.5 to 6.5 in hydroponics), the roots cannot absorb nitrogen efficiently, even if there is enough available. Regular testing and correction of pH will help prevent nutrient deficiencies, including nitrogen deficiency.

Balanced nutrition plan

A balanced nutrition plan is the key to ensuring that your plants receive the right nutrients at every stage of their life cycle. While there is an increased need for nitrogen during the growth phase, the amount of nitrogen should be reduced during the flowering phase, as the plant then needs more phosphorus and potassium. A balanced plan prevents both deficiencies and over-fertilisation, which has a positive effect on overall growth and yield.

With these measures, you can effectively prevent nitrogen deficiency and provide your plants with an ideal environment for healthy growth.