I feel confident that this rose is from Graham Thomas, or at least a near-Charles Austin descendent. I think GT is correct, though. I am unsure what else this rose could be.
Grew it when it was new, it mildewed, and I dumped it. I have had both Yellow Brick Road and Yellow Submarine for more than a decade now, and I find them far more preferable.
Mr. Graham Thomas was not interested in breeding roses I understand. He died in 2003. Michael would have been referring to the <2007 rose ‘Graham Thomas’.
'High Voltage' has been a beast in my Olympia, WA no spray garden. Even in about 1/2 day sun, I get minimal foliage problems. Every year I cut it down to about 2 feet. By the end of summer, it's about 8 ft tall. It requires no staking, either.
I live in Zone 8, so it was obviously hardy. But it did mildew, which is odd for here. It did not black spot here. I got the impression that this was was bred from Austin types, and probably also descended from something like Flower Carpet Yellow. I found Yellow Submarine and Yellow Brick Road to be superior garden plants. But I am told High Voltage is hardier than those two, which is too bad.
