It can happen that a cannabis plant gets curly leaves relatively early or at some point during its development. There can be several reasons for this. Here are the most important ones:
genetic predisposition
Some cannabis plants develop curly leaves because they have a genetic predisposition to do so. Most often, this phenomenon occurs in Hazes or Sativa dominant hybrids, which at the same time are extremely sensitive to fertilizers and overfertilization.
Overfertilization
Curly leaves can also result from overfertilization and when the soil is so enriched with fertilizer salts that the excessive salts in the soil deprive the plants of water. As a result, the leaves curl and dry up.
To solve this problem, the plant pot with the soil should be well rinsed with clean water, so that excess fertilizer salts are removed. For example, at least 5L of pure water should be poured into an 11L pot. The excess water will then run back out of the drainage holes at the bottom of the pot, taking the excess fertilizer salts with it. The next two times the plant needs to be watered, only water without fertilizer is used. Then continue with the addition of only a little cannabis fertilizer (1/3 to ½ of the previous amount of fertilizer) and watch the plants and leaves closely. If the curly leaves occurred due to overfertilization, the problem should resolve after a few days and the new leaves will continue to grow normally.
Confusion
If the daily exposure time is reduced to 12 hours and then switched back to an 18/6 rhythm, there may be more confusion in the cannabis plant. The leaves will then grow in a spiral.
too much heat/dryness
If the marijuana plant loses water faster through the leaves than it can absorb through the roots, the leaves react accordingly. Water is withdrawn from the edges of the leaves and the leaf edges roll up or down.
Countermeasures:
- Lower the temperature in the grow room
- Concentration on a healthy and robust root system of the plants
Root rot
If the planting substrate is not suitable or is too wet for too long, sufficient gas exchange cannot take place and the roots do not get enough oxygen. Under the aneorobic conditions, root rot then easily develops or roots die due to the lack of oxygen. The consequences can be seen in droopy leaves, the entire plant, and stunted growth. Finally, it can also lead to the death of the plant.
Overwatering
Overwatering creates the perfect environment for a wide variety of diseases. Many beginners think their plants aren't getting enough fertilizer and give their ladies even more. However, this makes the problem worse. Overwatering and overfertilization often occur in combination and cause problems and abnormalities such as curly leaves in many plants.