I need a butterfly friendly fungicide for my zinnias
I have a very large bed of zinnias (160+ plants) that I'm growing to attract butterflies and last year, many of them got brown crispy lower leaves. This year, I've only seen a couple brown leaves so far so I'm hoping there's still something I can do to prevent it that will not kill or repel butterflies. They're not blooming yet but almost, within the next couple days. I have lots of buds.
I've never had a mildew problem. This is something else. I'm pretty sure some kind of fungus, but possibly just nutritional.
My mistakes so far - I planted them in the same spot as last year, didn't clean up old plants very well, and I've been watering them overhead, almost every morning because they're small and we've had triple digit temps.
Someone in another forum mention powdered cinnamon for zinnias, but not sure if they meant for mildew or other diseases.
Whatever my zinnias had last year didn't kill them. They just looked terrible and of course didn't bloom as well as they should've so I don't think I need complete control.