Speaking only for myself, I think it's dumb luck that my zinnias tend to do well. I say that because I don't do anything special to them - just full sun, watering with drip irrigation when it's dry, and a sprinkle of fertilizer once or twice during the summer. I do get some fungusy-looking leaves on maybe a quarter of the plants, but even those plants keep on choogling and still produce pretty good flowers. I see that you're in zone 5 in Maine, so high humidity is probably not a big issue for you.

It seems that every so often I see a post here or there on the web by someone who says the same thing you do - zinnias just don't do well for them. Other than maybe having especially fungus-ridden soils, there often doesn't seem to be any obvious reason for it. If there was, I'm sure you would have figured it out by now.

Do you have any major fungus problems with any other flowers? Do you do sprinkler watering?

Sorry I can't be of more help, Martha. Maybe someone smarter can chime in.

ThinMan

Do you have any major fungus problems with any other flowers? Do you do sprinkler watering?

Humidity CAN be a problem. We are literally ON the ocean. I get mildew on some varieties of other flowers like blue boy phlox. I rarely use a sprinkler, most of my beds are drip or soaker irrigated. Perhaps I should devise a plan for my zinnia bed to either stake or provide horizontal netting for them and plant them farther apart from each other. I would just have to come up with another veg or flower to underplant so as to not lose too much bed space (maybe lettuce.) Do any of you others stake them?

Martha, do other folks in your area grow zinnias? I seem to remember reading somewhere that they do NOT like sea air. Might be the reason. Kat

I mulch my zinnia rows with straw, which works quite well against black spot on the leaves. At the first sign of mold/mildew, they get a spray of fungicide. If a plant starts looking funky, OUT it goes into the burn barrel.