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Cacti & Succulents

Black spots on the cactus

7 years ago

Hello everyone,

I desperately need help to figure out what's going on with my cactus!

Not too long ago, it was getting mealy bugs so I gave it a good soak with soapy water and then sprayed it neem oil. A week after, I put them in the sun and I started to see brown spots along the ridges. So I chanced the soil and I moved the cactus in the shady area just in case it was a burn but the spots are spreading more.

Does anyone can give me advices on what to do?

Thank you!

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Comments (3)

Christina Bay Area
7 years ago
last modified: 7 years ago
I'm not sure what is wrong, but I wanted to say that neem oil I hear can be harsh. Next time, you can just spray the plant with alcohol, or swab infected areas with alcohol soaked Q-tip. Some people like to dilute the alcohol with water, but I like to spray with full-on alcohol. It's very effective yet simple and it does not harm the plants.
Naraya Boo thanked Christina Bay Area
Kara 9b SF Bay Area CA
7 years ago
It was the neem. Now you know, but never spray with Neem oil then put in the sun. If there's Neem oil still on the cactus, might be a good idea to get it off. Some plants don't respond well to the oily substance. I use Neem oil, but always try to do a little research on the plant I'm about to spray and how it responds to Neem. Pretty sure your cactus will be fine:). It's all a learning lesson. Goodluck:).
Naraya Boo thanked Kara 9b SF Bay Area CA
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Naraya Boo
Original Author
7 years ago
Thank you so much! I will keep it in the shade for awhile and see what happens! I really appreciate your advices!

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