It could be too much water. Are they in soil that drains well? Have you had a lot of rain before this happens? When you planted these waves, did you spread their roots a little before putting them in the soil? Sometimes if there are a lot of roots in the pot and they aren't broken up somewhat before you plant them, they will keep growing around in a circle and eventually die. They'll grow fine at first, but then they will start dying. It could be a fungus too, but I haven't heard of any problems with them, and I haven't had any disease or bug problems.
Hope you find out what's happening! Good luck!!

Kat

In my experience with plants, sudden death usually means root rot or fungus. Are they in the ground or in pots? I've read not to plant petunias in the same place in the ground or with the same soil in a pot for 2 years in a row because of a fungal problem. I don't think it's the heat - petunias are fine in the heat. Do they turn yellow, or are they still green and suddenly wilt?

Deanna

The ones that died first this year are in a somewhat raised bed. They are planted at the edge, which is sloped, so the drainage is good. It hasn't rained here enough to count in three weeks, so they only get water from my sprinkler system (they are on a mister). I water well, twice a week. If they look dry I will hand water as well.

Yes, I always loosen the roots of plants before planting.
Our soil is heavy red clay, but when I created this bed I roto tilled it and amended with mushroom compost. This fall when I planted the waves I added a good soil conditioner. I haven't planted petunias in several years before last fall. When they died they didn't change color, just wilted and died.

I can pretty much grow anything else. Just not petunias!
If it is a fungus, is there a particular fungicide I can apply to the few that haven't died yet?

Thanks for your help!

Susan

I have experienced Wave Death in southeast Texas - again, plants did well initially but over a period of days began languishing and dying in the late spring heat.

It's possible that this type of petunia is susceptible to some kind of fungal or bacterial disease that is a particular problem in hot weather (i.e. deep South 90s during the day and above 70 at night for months on end). Do other sorts of petunias (grandifloras etc.) perform better in your climate?

I googled and came to this site. I have the same problem. Some are great. Others in same pot withered and died. Conincidentally, they are pink/lavender. I saw some others on this site under wave petunia that described the same color. Do you think it is color related? Very disappointing

I have been having the same problem for years. It used to be that only my regular petunias would do this. But this year my wave petunias in pots are doing the same thing. It is something that is spreading because it started in one pot and spread to a pot that was ten feet away and when it started in the second pot it started on the side that was closest to the other pot. I am glad to hear I am not the only one. For years I couldn't fine anything on it. I have asked at several nurseries and no one ever seems to know anything about it. Like it was stated in a previous post I can grow any other flower in the same soil.

I too had the same problem and I stopped growing them several years ago. I had planted them in pots, as well as in the ground. One day they looked great and the next day--sudden death. All the other flowers in the pots or in the ground near the Waves--no problems.

Petunias and pansies- I forget where I read it, but they should not be planted two years running in the same spot, because of fungal diseases specific to the plant. These develop in warm weather climates in particular.
Renee

Don't plant any petunias in same spot next year is my suggestion. My dear MIL never planted her tomatoes in same place every year. No problems except with the squirrel feasting on them and she always had a beautiful garden. One year she would plant the garden with the rows one way; the next year, they would be just the opposite way. Something the Pa. Dutch people did in their gardens.

If it is fungus what can I do