by Wally Richards

BLACK SOOTY MOLD

From my search engine Perplexity comes the following….

Black sooty mold is a fungal disease that appears as a dark, soot-like coating on plant leaves, stems, and twigs. It doesn’t directly attack the plant but grows on honeydew, a sticky, sugary substance excreted by sap-sucking insects such as aphids, whiteflies, mealybugs, and scale insects.

The presence of sooty mold is often an indicator of an underlying insect infestation.

The Characteristics and Effects:

Appearance: Sooty mold looks like a layer of black or grey fireplace soot over plant surfaces.

Growth: It can vary from a fine, powdery deposit to a thick sheet that may crack or peel during dry conditions.

Impact: While not directly harmful to the plant, a heavy coating of sooty mold can:

Block sunlight, reducing photosynthesis and slowing plant growth.

Make the plant appear unsightly and In severe cases, reduce overall plant vigor.

Causes and Associated Factors:

Sap-sucking insects feeding on the plant, producing honeydew.

Poor air circulation and high humidity, which create favorable conditions for fungal growth.

Some plants, like gardenias, citrus and roses, are more susceptible due to their proneness to pest problems.

Prevention and Control To manage sooty mould:

Control the underlying insect infestation using appropriate insecticides or organic methods.

Improve air circulation by pruning crowded branches.

Encourage natural predators like birds and beneficial insects to control pest populations.

For the fastest removal of black sooty mould use Wallys Karbyon.

Karbyon is a new product that solves a problem which a solution has been sort after for years; to remove black sooty mold off plants.

Called KarbyonTM it is micro encapsulated potassium bicarbonate 900 g/kg in form of water-soluble powder.

It’s used at 50 grams per 5 litres of water. (A scoop provided in container is 50grams when filled level)

To mix place 2.5 litres of water in spray tank, while mixing slowly add the 50 grams of KarbyonTM then the other 2.5 litres of water (warm water will be better).

When spraying ensure a good spray coverage to run off for optimum disease control.

48 hours later spray the target plant with a jet of water from the hose. If not all the sooty mold is removed, then a second application of KarbyonTM may be needed.

There is a withholding period which is; Do not apply within 7 days of harvest of food crops.

Storage Instructions: Store below 35C. Keep out of reach of children.

Store out of direct Sunlight. Keep container tightly closed. Do not store diluted product.

Karbyon is used for not only removing black sooty mould off plants but also for the prevention of powdery mildew on plants. That means it will also help prevent black spot on plants.

For either of these uses I would recommend adding Raingard to the spray so it does not wash off in rain for up to 14 days. If using for black sooty mould then do not add Raingard to the spray as you want to wash it off after 48 hours.

The cause of the black sooty mold is insect pests such as whitefly, scale, mealy bugs, aphids and thrips all of which feed on your plants and then pee out honey dew. The honey dew turns to black sooty mold and also attracts ants.

You can do one of two things: firstly kill the insects that are causing the problem by spraying Neem Tree Oil and Wallys Super Pyrethrum mixed together; or you can treat the sooty mold first and then the insects afterwards. Also the placing of Wallys Neem Tree Granules under the plants and in particular with citrus trees in the root zone also helps with insect pest control.

Black sooty mold not only makes the plants unsightly it also reduces the energy the plant can obtain from sunlight. If they are not getting the energy they should pest insects will be sapping their vital energy as well. The plants are in stress and can lose leaves, fruit, flowers and eventually die.

A real problem on citrus trees is from the Australian White Fly which arrived in Auckland in 2000 and now has spread over a lot of the country.

At least now you have a means of removing the sooty mold.

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