New flower bed that faces south and gets full sun all day. The long end is 12', shorter end is 6' and the bed is 4' deep.Would like to plant something that doesn't get really tall. Annuals don't live long under my care so I need something that is somewhat lower maintenance. Was thinking drift roses might work good here? I have regular knockouts on the west side of the house that do good but they do get huge. Would appreciate any advice on drifts and how many I should plant in the beds. I am in zone 8b. Please excuse the messy porch/yard, too many projects going on at one time:)