Blemish? Question. Black stuff on cacti Question.

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JCcares
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Blemish? Question. Black stuff on cacti Question.

Post by JCcares »

See images. Looks similar to mold in my shower. What is it do I need to be concerned do something about it?

Thank you very much for sharing your knowledge
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My name is Joe I Live in Hickory NC USA four equal perfect seasons.
Pd1973
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Re: Blemish? Question. Black stuff on cacti Question.

Post by Pd1973 »

opuntia looks healthy, you have no reason to panic, it is a hardy cactus.
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JCcares
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Re: Blemish? Question. Black stuff on cacti Question.

Post by JCcares »

Pd1973 wrote: Fri Aug 26, 2022 2:03 pm opuntia looks healthy, you have no reason to panic, it is a hardy cactus.
Thank you. Awls I know is it wasn’t there a few weeks ago and not sure that this opuntia Argentina was safe.

After spider mites over the winter I guess I’m just paranoid now about any little blemish. Thank you again 🙏🏽
My name is Joe I Live in Hickory NC USA four equal perfect seasons.
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JCcares
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Re: Blemish? Question. Black stuff on cacti Question.

Post by JCcares »

JCcares wrote: Fri Aug 26, 2022 3:11 pm
Pd1973 wrote: Fri Aug 26, 2022 2:03 pm opuntia looks healthy, you have no reason to panic, it is a hardy cactus.
Thank you. Awls I know is it wasn’t there a few weeks ago and not sure that this opuntia Argentina was safe.

After spider mites over the winter I guess I’m just paranoid now about any little blemish. Thank you again 🙏🏽
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My name is Joe I Live in Hickory NC USA four equal perfect seasons.
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greenknight
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Re: Blemish? Question. Black stuff on cacti Question.

Post by greenknight »

When you said "similar to mold in my shower." you pretty much nailed it. Could be due to extrafloral nectaries, which many plants have, including many cacti. These secrete nectar on various parts of the plant to attract ants, which benefit the plant in a number of ways. If ants don't clean up this nectar, it often grows black mold, which is unsightly but harmless.
Spence :mrgreen:
DaveW
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Re: Blemish? Question. Black stuff on cacti Question.

Post by DaveW »

You may be able to blast it off with a fine water spray. I use one of the pump up mist sprayers with the nozzle twisted to produce a needle jet instead of spray. You can also use a spray on fungicide to help stop it forming. As Spence says it is not usually detrimental to the plant, but can be unsightly if excessive.
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JCcares
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Re: Blemish? Question. Black stuff on cacti Question.

Post by JCcares »

DaveW wrote: Sat Aug 27, 2022 10:10 am You may be able to blast it off with a fine water spray. I use one of the pump up mist sprayers with the nozzle twisted to produce a needle jet instead of spray. You can also use a spray on fungicide to help stop it forming. As Spence says it is not usually detrimental to the plant, but can be unsightly if excessive.
Thank you again Dave!!! Will try that.
My name is Joe I Live in Hickory NC USA four equal perfect seasons.
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JCcares
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Re: Blemish? Question. Black stuff on cacti Question.

Post by JCcares »

greenknight wrote: Sat Aug 27, 2022 1:06 am When you said "similar to mold in my shower." you pretty much nailed it. Could be due to extrafloral nectaries, which many plants have, including many cacti. These secrete nectar on various parts of the plant to attract ants, which benefit the plant in a number of ways. If ants don't clean up this nectar, it often grows black mold, which is unsightly but harmless.
Thank you GreenKnight!!! You teach me so much!!!! Appreciate your willingness to help us newbies.
My name is Joe I Live in Hickory NC USA four equal perfect seasons.
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