How much water does my potted Belinda's Dream rose need?

I got it this spring, and it's not doing well. I mistakenly potted it using dillodirt, since that was all I had at the time. Two weeks ago, I repotted it using good rose dirt from the natural gardener, great organic place. I'm hoping it will rebound, but am not sure how frequently to water it. It's in a large pot, with 2 inches of mulch.

Thanks!

Stick your index finger all the way down in the soil. if it is dry when you pull it out then water

Makes sense. Thanks.