| Hello...
I'm an amateur gardener raised in humid, temperate New Jersey, currently living in arid, subtropical Lima (Perú). I have four specimens of 'Aloysia triphylla' I've bought at different markets that have all developed this strange disease on their leaves... rust-colored blemishes surrounded by yellow, with the leaves and branches becoming brittle and the former coated on the bottom with a powdery dirt-like substance that resembles some sort of bluish fungus.
I have four questions, if you would be so kind as to drop me some hints:
1. Lima's weather is bone dry with the only humidity coming from the nearby ocean -- can fungus spores become airborne on sea mist? I mean, I was used to seeing fungus kill European grapes in Jersey; but I thought I had left that problem behind when I arrived in Lima...
2. I thought perhaps the plants were suffering from too much sun, which might be triggering water stress; but then if when I moved them to a shadier location, the locals told me it was bad for the plants, which apparently love the difficult combination of full sun + plenty of water... so does anyone know exactly what type of environment Aloysia triphylla is native to? Maybe that can shed some light on what is causing my Lemon Verbena plants to die while nearby farmers easily grow three- to five-foot tall bushes :(
And...
3. Any insight on what determines whether three-leaf whorls predominate over pairs of two at each node? I have two plants where almost every node bears the classic whorl of three leaves, and two strange specimens with basil-like pairs of leaves at each node.
Sorry if I wrote a book, but this plant fascinates me. I will be very grateful for any information anyone out there can provide me.
Thank you...
Ron
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