The problem could also come from your ph being too high or maybe too much sun for its respective age.
Don't think that it's the sun; they're in a mostly shady situation and only get early morning or late afternoon sun directly.
It might be the pH, though, except that three of the four are where they are getting rained on directly. Only one is getting filtered water given manually because it is in a 4" pot. And as earlier mentioned they have been given 1/4-strength water-soluble fertilizer about every third or fourth watering.
And on all four of these individuals the new leaves emerge, expand, and mature perfectlly green and healthy. It is only a few weeks later that they start to show edge burn –and that is usually after the next set of new leaves has emerged and matured.
I'm wondering whether it might be the amount of water that they are receiving. I was told by the seller in HI that in nature they receive a
lot of water in their native habitat.
It's all very curious and I'd really like to succeed with these cambucá!
¡Saludos! William . . .
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