I've found they usually like the lighter colors best here. Tiffany has been hit the hardest. I don't see them much at all in the darker ones and I don't think I've ever found any in the dark reds at all. Maybe they're color blind?

I have 125-130 rose bushes & the only 2 roses I've seen them leave alone are 'Lavaglut' & 'Ramblin' Red'. I have a bad JB infestation in my area because I'm 2 blocks from a large, irrigated University athletic field. Some years the JB population is so bad that they eat the summer cycle rose buds before they even open. And it isn't just flowers & buds, they also skeletonize the leaves of my old garden roses that don't repeat & aren't in bloom with the JB's show up. They seem to start on the fragrant, light colored roses first but once they find your rose garden, pretty much everything is fair game.

WIrosarian is correct and it's pretty much like asking what can I plant that the deer won't eat? The answer is, it doesn't matter much because it depends on what they feel like that evening and if they can reach it, it's fair game. Same with the beetles, which begins here with rose chafers, different in appearance to JB's but oh, so alike in appetite. RC's emerge same time as the first roses begin to bloom. Early or late, I don't know how they time it but they time it right. Yellow's are goners for sure, followed by white and pink roses. Fragrance simply draws them in like a magnet, all of which means my old garden roses get devoured. Reds and dark colors will get eaten sometimes too, poor Bayse's Purple and scarlet red Eddie's Jewel this year being prime examples of apparently delicious petals.
After a month or so of the rose chafers, the JB's continue the assault, basically following the same preferences. My poor Polereis has not had an undamaged bloom all year. And some roses like Morden Sunrise have leaves that are entirely skeletonized. Yes, once they've found your garden, more beetles will come. They send out chemical signals to advertise the bounty they've discovered. But do you know which rose in my garden seems untouched by either evil beetle? Yup, the Double Knock Out that the previous owners had planted. Figures, doesn't it?

And so far, neither bug is interested in my daylilies. Small wonder why the number of DL's I grow is fast approaching and ready to surpass my roses! At least diverging into other collections allows me to separate and mix the roses in between other plants. Sometimes that helps a few rose blooms to escape detection here and there. My worst garden for damage is the strip along side the garage (facing east and prime rose territory) where I planted a long bed of mixed yellow rose varieties and purple and blue tall bearded iris behind. This was planned and planted before I realized the rose chafers here in the village are just as bad as they were out in the country where I was surrounded by hundreds of acres of fallow fields (their prime breeding ground.) And it was before I knew I ALSO had Japanese beetles here to contend with. That bed will have to be dug and redone at some point because it's just too painful to see all the damage there in a row with nothing else to look on.

Cheery, no? Still, I continue to tend my (fewer) roses and hope for the best. Maybe NEXT year, the beetle count will be lower and I'll see more blooms....hope (and gardening) springs eternal!

I have a theory: they seem to like my Asian lilies more than my roses. That said, they still get on those roses, but I've been picking them off my lillies assiduously. They are so gross!

Saw two of them on my 'Molineux' rose, a yellow rose about a month ago.

Beetle traps incorporate rose scent for the ladies plus female JB pheromones for the gents, and a blob of yellow for a visual target.

If you have fragrant roses in bloom, the scent will attract beetles to the yard, and then they home in visually to blobs of bright color, generally preferring lighter colors to orange, deep purple, and red, but also preferring whichever plants are prominently placed and in full bloom. Removing all the flowers before buds open will reduce the JB traffic in your yard. Gathering beetles every day and bagging them will cut down on the female sex attractant in the air.

In my neck of the woods, every rose in the garden was fair game this year. Even Pink Pet was destroyed. And they have never touched Pink Pet before. They'll be gone in a few weeks and I can start cutting back for the fall.

Oh well, it was worth a shot asking! Thanks everyone.

Some of the JB 's favorites in my garden are: PJPII, South Africa, & Beverly.