I've been told that dahlias just won't survive in my area's brutal summers, but having managed to keep a border variety alive (despite powdery mildew) I'm ready to step up to the big leagues and try a dinner plate variety. Are there commonly available varieties that perform better in hot, humid conditions?

Welcome to NGA UncleWill! Where would you be trying to grow dahlias? They are successfully grown from coast to coast and border to border. Like most plants they do have preferences, but are really adaptable to most areas.

I'm growing in south eastern NC. My yard has a profound lack of shade, it sits in the middle of open fields so the sun bakes it all day. I do have some shade under a line of pines but they quickly suck up any available moisture. Exposure to wind may also be an issue ( i understand that can be an issue but they would be caged once established).

Hi UncleWill!
If you google "The Dahlia Society of Georgia Heat Tolerant List", there is a PDF that should pop up in the search results that lists several dahlias that perform a bit better in hot and humid climates. The list isn't super up to date (I think it was last updated in 2013?), but it is still a useful guideline.

They will undoubtedly need to be staked. We all experience winds which will take them down. They are best grown in full sun but many of us have to deal with some shade. Some of the colors may not stand up to your sun. They will need to be watered regularly too. They may droop during the hot part of the day, but should perk up with cooler evening temps.

If you click on your profile you can add some info such as your zone and location which will allow others in your zone to be able to help with questions.

Welcome to the dahlia forum, UncleWill! I have family in SW Virginia who grow a lot of dahlias. I'm not sure what zone that is but I've been down there on some brutally hot days. I have no idea whether your area would get hotter and more humid than their's in a more mountainous area. We get enough heat in NE Ohio to make the dahlias wilt terribly during the day but they have always perked up by morning. We also get some mildew during humid periods. There are/were at least a couple dahlia suppliers in NC, not sure what part. That would be a great place to ask about heat resistant varieties. Dahlias are certainly worth a try.

As Gary said, dahlias definitely need to be supported, especially the larger dinner plate types. We often get high winds from Lake Erie in the spring and fall. I start staking mine when they're 12-18" tall.