It looks to me like the Iceberg is planted RIGHT NEXT to, as in practically up against, the Eden. It's quite possible the Eden is sucking the available water from the soil before the Iceberg even knows it's been watered ;) You're going to have to make sure there's enough moisture for both roses.
It's never a good idea to plant a new rose practically in the same space as an established one. With two roses as robust as Eden and Cl. Iceberg, even planted at the same time, with plants of comparable size, I wouldn't plant closer than 18 inches, preferably more. They are going to compete (read:fight over) for resources. Right now, Eden is winning.
