potassium cannabis

Excess or lack of potassium in marijuana

Chemical symbol for potassium with two cannabis leaves

The symptoms of a deficiency or lack of Potassium in marijuana plants are easy to recognize, as long as you’ve read this article before of course… So, I’ll explain you how to identify this nutritional problem.

🚀 Lack of Potassium Symptoms

  1. Older leaves start yellowing from the tips inwards
  2. The stems and petioles of the leaves weaken and cease to be erected.
  3. Plants become more vulnerable to pests and diseases
  4. Development rate slows down, affecting final production

Image of a cannabis plant affected by a severe potassium deficiency*

Now we are going to take a closer look at each of these points, to facilitate the task of identifying a Potassium deficiency in cannabis.

1 Why do you see it earlier in the older leaves? This is because Potassium is a macro-element, and these are mobile within the plant, so when it lacks to form new shoots, it takes the stock from the lowest leaves.

2 The stems and petioles of the leaves lose strength for several reasons, the main one being malnutrition itself, but they are also weakened by the inability of the leaves to carry out photosynthesis properly.

3 Many times the lack of nutrients in weed is associated with other misfortunes, such as pests and fungi attacks. This is because when the plant is healthy it has a much stronger immune system, just as it happens to us humans.

4 When cannabis plants are healthy, it is almost as if their growth can be seen with the naked eye, it is the plant that develops fastest. But that speed slows down drastically when they lack some macronutrient, something that is easily perceived.

✅ What causes lack of Potassium?

  1. Poor substrate quality
  2. Inadequate PH
  3. Excess Calcium blockage in irrigation water or substrate
  4. Lack of Potassium in the nutrient solution
  5. Blockage by excess of salts in general

As a general rule, when we suffer a deficit of Potassium in cannabis crops is for one of those 5 reasons but, why does this happen?

1 We all have met a grower friend who, by trying to save some money on substrate, ends up buying a low quality one. This is a big mistake, you save a small amount and it will usually cause you problems, so we strongly recommend growing with quality soil.

If we cultivate with a quality substrate and detect that the plant lacks Potassium, it can only be for one of the other 4 points. What we usually do is discard until we find the problem, more or less like doctors do.

2 The pH of irrigation water is very important for the absorption of nutrients. Potassium has an optimal pH range between 6.1 and 7.1 approximately, so values above or below that range can cause a lack of K.

3 An excess of Calcium can cause a lack of both Potassium and Magnesium. The balance between the elements that nourish the cannabis plants is indispensable, because some are antagonists of others, and when there are excesses of ones they can provoke the blockage of others.

4 All the cannabis varieties do not eat the same, in nature the Landraces have been adapting to their environment over the years. But today most commercial genetics are hybrids and polyhybrids, with different nutritional needs. Sometimes it happens to us that because we are afraid to use too many composters, we give them less fertilizers than plants need at that moment, causing a deficit of Potassium among other disorders.

5 This usually happens in crops where the plants have been in the same pot for a long time. It is due to the accumulation of salts in the root system, since roots do not assimilate the whole fertilizer, and the excess remains in the substrate, which gradually interfere with the perfect absorption of nutrients. The use of Enzymas and root washing corrects this problem.

Image where you can see the evolution of a lack of Potassium in cannabis leaves

🔥 Too much potassium in the marijuana plant

Besides the lack of potassium, it can also be in a situation of excess thereof, therefore, blocks the absorption of other minerals, such as calcium, magnesium, manganese, zinc or iron..

This excess, visually, causes the plant has a much darker color. If in the case of lack plant was becoming yellowish, in this case it turns dark brown. In addition, it will give way to other multiple deficiencies caused precisely by this overfertilization.

If this is your case, but still time to save your plant because this is not dead or has not been greatly affected, you must take charge and give you a solution. Is there any perfect? The word would not be perfect, but simply a quick and effective response to the problem that your plant right now.

Thus, in these cases, the solutions to follow are the following: firstly, a wash of roots, so that they can return to absorb all the nutrients. They are getting your plant develops as expected it. Some may even improve many of the processes that follow the plant until we collect the fruits expected during harvest. Returning to the subject of washing, it is recommended to do so with at least triple water capacity of the container.

During this root cleaning, we can also add an enzyme solution to the water with which we water our plant, helping to break down the salts and thus leach the substrate. Once this step has been carried out, it is recommended to water with a light and complete fertilizer.

Do you recognize with the naked eye a lack of potassium in cannabis crops? ⚠️ In this article we easily show it to you ✨ It will never affect you again.