I like annual Vinca's for certain areas that I'm don't have irrigation and they are awesome for bedding.

This year, with the super wet spring, I ended up doing a second round of planting as the 1st ones - slowly , each one aborted due to the very WET spring we had.

Now, as cooler days are upon us, sofar I've yanked 3 out as they went into decline (curled leaves, yellowing, etc)

Last year, all of them fared fine all the way close to the hard frost.

Any ideas/clues on what's causing the -established- vinca's to yellow off and abort. temps on average is around high 70's this time of the year