Yellow spots on plant leaves? Here’s what to do in the case of leaf septoria

Yellow spots on the leaves: causes and remedies.

Modified on: 27/04/2022

Causes and solutions of leaf septoria, a very common disease that stains the leaves of plants yellow

The yellow spots on the plants’ leaves are the clear symptom of a fungal disease, specifically called leaf septoria or, more simply, Septoria.

Among the plants most affected are those of tomatoes and those of cannabis … And imagine what a tragedy, for those who sprout marijuana seeds and take loving care of the seedlings in every phase, to see the foliage spotted with yellow.

Today we want to tell you exactly how to manage this plant disease and prevent yellow spots on the leaves, to prevent them from recurring.

You can apply our advice to any plant, but beware of marijuana: planting cannabis seeds is, in the UK, an administrative offence or a criminal offence depending on the case, so we advise you not to develop this practice.

However, auto flower seeds, feminized seeds, and fast flowering weed seeds can be purchased for collecting or cultivated in countries where the UK’s restrictions do not apply.

And now, let’s focus on leaf septoria and remedies for this particular disease.

Leaf septoria: the cause of yellow spots on lemon leaves, tomatoes and many other plants

The spots on the leaves, when they appear yellow, are most likely caused by a fungus of the type Septoria. The most common is Septoria lycopersici, but the one that attacks hemp leaves is Septoria neocannabina or Septoria cannabis.

This fungal disease affects cannabis and numerous other plants, such as lemon and tomatoes, and causes the entire attacked plant to weaken.

The symptoms of leaf septoria are very evident, although the fungus first affects the oldest leaves, therefore lower on the plant. Here are what symptoms we talk about:

  • Spots on the leaves, circular, turn from white to yellow to brown, similar to small lesions.
  • In the later stages, the lesions on the leaves become lump-like.
  • As time passes, the lumps increase in size and quickly spread over all leaves.
  • The affected leaves dry out and fall off.
Plant leaf septoria symptoms

This disease does not cause the plantation’s death but drastically reduces the extent of flowering and, therefore, the harvest. It is, therefore, essential that farmers take the necessary measures to block the spread of Septoria.

It is not, therefore, a mere question of aesthetics! The yellow spots on the leaves are the symptom of a disease to be blocked immediately, first of all, investigating the causes.

Read also: The growth stages of the autoflowering plant step by step

Causes of Septoria: the fungus that storms the leaves of plants with yellow spots until they dry out

As you may have read, the cause of the yellow spots on the leaves is a fungus called Septoria, which spreads rapidly on both the affected plant and surrounding plants.

But what causes this fungus to develop? How to prevent it from forming on plants?

The first reason that leads to the development of leaf septoria is the high humidity rate, followed by a possible nitrogen deficiency.

If the soil is too wet, the stems grow closely together, or there is a lack of the essential nutrients for plants, then the conditions are perfect for developing the septoria fungus.

Therefore, to prevent the disease, it is good practice to avoid growing plants too close to each other, constantly monitoring the relative humidity rate and the nutrients present in the soil.

Another “trick” is to water the seedlings in the early morning or at the latest in the late afternoon. It helps to prevent the earth from remaining damp for too long.

Watering in the morning helps to avoid leaf septoria

But what to do when Septoria begins to affect plants?

How to manage and treat leaf Septoria

Here’s what to do in case of yellow spots on the leaves of the seedlings:

  • Eliminate fallen leaves immediately.
  • Destroy the diseased leaves still attached to the stem.
  • Avoid letting fallen diseased leaves stay on the ground for too long.
  • Disinfect every tool used on plants well.
  • After the harvest, it is essential to till the soil well, feed it with sterilized compost and add some fungicide before starting a new plantation. The spores hide in the earth, ready to attack the next plant.

If leaf septoria continues to attack your plants despite the precautions, then it’s time to use fungicidal sprays on the leaves not yet, affected!

Yes, because fungicides are unfortunately unable to cure leaves already affected by Septoria, they protect healthy leaves from the disease.

The most used fungicides include:

  • Chlorothalonil
  • Maneb
  • Macozeb
  • Copper-based fungicides such as copper hydroxide, copper sulfate, or copper oxychloride
  • And many more.

To take their course, you need to follow the directions written on the bottles to the letter.

Read also: Hashish and marijuana: differences, effects and varieties

In conclusion

Now you know all about the causes, prevention, and solutions to yellow spots on leaves caused by a fungal disease called leaf septoria.

We know how annoying it can be when a parasite attacks plants, but luckily, we have all the weapons to fight this situation.

Did you find this article interesting?

So, if you like it, feel free to share it on social networks and visit SensorySeeds, our online marijuana seed shop! A world will open up to you!