Thanks. 2 votes against it is sounding like a no go, unless anyone has a dissenting opinion.

I did notice that the Urban Harvest sale didn't have them this year...

Besides the fruit not being sweet, my now-departed vines did not live up to the "hardy" part. Some grapes did get fungus. Muscadines are both hardy and sweet. A self-fruitful variety like Ison could provide fruit for many years. They taste like the Welch's grape juice that is similarly dark purple in color. Unlike the bottled juice, the muscadines do have seeds. As do the Mortensons.

In Sylvania, Georgia is a Muscadine vineyard.
Many of the vine are over 20 years old & still going strong.
They are used to make wine & to eat.
I have a a table grape that a friend gave me.
He said it was an Italian wine grape.
I have had it for 10 year & he has had his over 25 years.
It is not too sweet, but I like it.

Putting this out there for posterity, but yes, Mortensen Hardy is capable of reaching 26 brix (that’s high, more than any muscadine), and has a slight pineapple flavor when fully ripened. The key is it takes a long time to reach optimal ripeness, at least a month after verasion. Berries are large on medium sized clusters. The vine is susceptible to anthracnose and black rot, but not nearly as bad as blanc du bois. Overall, I recommend it. Could possibly be a good neutral wine as well.

I have grown them in my yard for years in Houston, Texas. when not-quite ripe they are quite sour, grown in a form on either side of a central stem, rather than in bunches. Because of lack of space, we trellesed ours. they grown up the sides and top of a ten foot rectangular trellis, and cover the roof. They are VERY vigorous growers. They will sweeten, but suddenly over a few days, so, if you want them sweeter, you have to keep sampling. when ripe, the birds go crazy and eat them all, also squirrels, so you will need to keep sampling and harvest promptly. Perso Personally I prefer them sour. they have more charachter.