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Brown spots on Mint after spraying with Neem Oil

Hello, this forum is great by the way ! :D

I was wondering if an expert here could have a look at my discolored Mint leaves :arrow:

:idea: This is growing in a pot outside on my balcony (I live in a flat), and as a preventative measure I sprayed it with Neem Oil.
It looked fine before the spraying, so I am wondering if maybe it was the Neem Oil that did this :?:

Any help would be greatly appreciated ! :)

Thank you

Cool Member
Posts: 78
Joined: Fri Feb 19, 2010 1:13 am
Location: Houston, TX

I have similar spots

I have similar spots on my mint. I didn't spray with neem oil, but there was neem oil in the watering solution. Hm....

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Super Green Thumb
Posts: 25279
Joined: Sun Feb 15, 2009 6:04 pm
Location: TN/GA 7b

Mint is very tough and is insect repellant. I would not bother spraying it with anything preventatively. Mint oil is used to keep insects away from other plants!

Cool Member
Posts: 78
Joined: Fri Feb 19, 2010 1:13 am
Location: Houston, TX


I am thinking, if the spots might be due to too much fertilizer.

Here is the history:
When I planted the mint, I mixed some powdered fertilizer in the soil in the ratio stated on the fertilizer package. (5 nitrogen 5 phosph. 5 potash) The package said that the fertilizer can be used every 30 days. But I decided to go 2 mos before fertilizing again.

4/30 & 5/15: I gave the plant some liquid fertilizer that contains nitrogen & potash. This fertilizer says it can be used every 2 weeks. And I did use the ratio as listed on the bottle.

Neem oil/soap flush: The last time I flushed the mints with neem oil was 4/19. So that was a whole month ago.

Watering: I'm watering with the cinnamon & chamomile mixture (2 chamomile tea bags + 1 cinnamon stick per 1 gallon of water) on a regular basis.

It seems like to me that I didn't have any spots until I put that liquid fertilizer. I've been using the liquid fertilizer on the other plants with no problems, but I am thinking it might be the fertilizer...

I think I will go completely off fertilizer for a month and see what happens. Any thoughts?

(Also, I still have a few fungus gnats but they are much reduced from before.)

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