LEAF SEPTORIA VS. CALCIUM DEFICIENCY IN CANNABIS PLANTS: HOW DO THEY DIFFER?

A lot can happen when growing cannabis, and most of the time these problems manifest themselves on the leaves. Two common problems that cannabis growers encounter and have to learn to distinguish between are leaf septoriosis and calcium deficiency. It is therefore important to check the plants regularly to detect any symptoms appearing on the cannabis leaves early on, which could be a sign of nutrient deficiency or infection. In fact, recognising signs of disease or nutrient deficiencies will allow you to take immediate corrective action.

Since many of the symptoms of leaf septoria and calcium deficiency are similar, it is important to recognise and differentiate between them. In this article, we will look at the differences between leaf septoria and calcium deficiency in cannabis plants and how to deal with them.

What is leaf septoria?

Leaf septoriosis is a fungal infection of cannabis plants. It first appears on the lower leaves and causes mottling and yellowing of the leaves. The cause of the disease is usually the fungus Septoria lycopersici. It occurs mainly in summer, when high temperatures combined with rain or moisture from watering cause the leaves to become wet.

Untreated leaf septoria causes cannabis plants to show symptoms of chlorosis, a condition that prevents the leaves from producing enough chlorophyll. Although septoriosis does not kill the plants, it will reduce their yield. Early interception and intervention are essential as the disease can spread to other plants through wind, water and insects.

How to avoid cannabis leaf septoria?

It is always better to prevent diseases and pests than to deal with them afterwards. To prevent or at least reduce the likelihood of leaf septoria , do the following:

• Clean your grow site regularly, especially if you are growing indoors.

• Space the plants further apart to retain moisture and reduce humidity.

• If you are growing indoors, make sure the room is at the right temperature .

• Make sure there is plenty of fresh air flow.

• Prune the plants regularly.

What should I do if septoria appears on cannabis leaves?

If septoria appears on a plant, you can take the following steps once it has been detected:

• Immediately remove all affected leaves.

• Trim all leafy parts of the plant to improve airflow.

• Keep the soil under the plant clean. Rake up all fallen leaves. You can also prevent the spread of disease by adding mulch.

• Monitor temperature and humidity. You can lower the temperature by using air conditioning.

• Do not water the plants from above. Watering from above will wet the leaves, which creates the right conditions for fungus and disease.

• Copper-containing fungicides or biofungicides can be effective in preventing the spread of fungi.

What is calcium deficiency in cannabis?

Calcium deficiency is the cause of calcium deficiency in the plant. Cannabis plants need important nutrients such as nitrogen, phosphorus, potassium and calcium for proper growth. To reach their full potential, cannabis plants need calcium at all stages of their growth, from seed to harvest, even at flowering stage. Calcium contributes to the formation of healthy roots, strengthens the stem and reinforces its structure.

Calcium deficiency in cannabis results in symptoms on the leaves that resemble leaf septoria. Calcium deficiency causes bronze to brown spots to appear on the leaves of cannabis. If left untreated, these spots will turn red or dark.

How to treat calcium deficiency in cannabis?

The best way to deal with this problem is to supply the plants with a fertiliser containing a high amount of calcium. Watering is also a good option. A water solution with a neutral pH should balance the nutrient levels in the substrate.

Leaf septoriosis vs. calcium deficiency: Five main differences

Calcium deficiency and leaf septoria can be very similar, but can be distinguished by the appearance of the plant. Note the following factors:

The colour of the leaf spots

Leaf septoriosis produces yellow spots on the leaves that turn dark brown or tan in colour. Plants with calcium deficiency have a yellow-green colour at the beginning and towards the end the leaf colour changes to reddish brown.

Distribution of leaf spots

If the spots are only on the lower leaves, it is very likely that it is septoria. This is where the fungal infection begins.

Root strength

If the leaves of the cannabis plant are turning over, this may indicate that the plant has weak roots. This is a sign of calcium deficiency, not leaf septoria.

pH level

By checking the pH level in the soil, you can easily tell if the plant has leaf septoria or just a calcium deficiency. A normal pH indicates leaf septoria, while a low pH indicates a calcium deficiency.

Weakness of the branches

If the calcium supply is insufficient, the twigs are immediately weakened. Leaf septoria does not initially affect the vigour of the plant. The whole plant only weakens when the infection is left untreated.

Leaf septoriosis and calcium deficiency

When growing cannabis, it is important to be observant of any spots on the leaves. Problems with leaf septoriosis and calcium deficiency are easy to deal with, so it is important to learn to recognise the symptoms early. Both problems can be corrected by using the right fertiliser, but it is important not to overdo it with the amount of nutrients and additives added to the soil.