Oleander dehydrated or infested?

Question

My oleanders are in pots on a balcony in Sydney Australia, and have thrived there for years. In recent weeks they are browning at the tips and down the sides of some leaves, there is some yellowing with a scribbly pattern on one plant, and some leaves have brown spots. It’s possible (but unlikely) that they had insufficient water in a recent hot spell. It’s also possible it’s something else. We don’t yet have leaf scorch in Australia (unless I’m the first!), though the descriptions fit some of the symptoms. Any advice would be much appreciated.

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Answer 1

That is, certainly, an infection. There are many kinds from bacterial, to fungal, to viral.

Most can be cured easily. The best way for a potted plant will be to replace 1/4 of the water with peroxide the next time that you water. This will kill off the infection. You will only have to do this once, and when it is needed in the future.

This article will give you more information on the care of these: https://www.gardeningknowhow.com/ornamental/shrubs/oleander/growing-oleander-in-containers.htm

Answer 2

Thanks that’s most helpful and an entirely new approach. I presume that’s 1/4 at 3% peroxide concentration ?