Q.knockout roses have yellowing leaves
Some of my knockout roses have yellowing leaves. Am I overwatering? Under watering? My roses are newly planted and I’ve never cared for this type of plant before. How often do they need water?

Here is an article that will help you that discusses why rose leaves turn yellow - it will give you specific guidelines on how to water:
https://www.gardeningknowhow.com/ornamental/flowers/roses/yellow-rose-leaves.htm
For more information on the care of knockout roses, please visit the following link:
https://www.gardeningknowhow.com/ornamental/flowers/knockout-roses/care-knockout-roses.htm

once established your roses should be watered when the dirt feels dry about 2 inches deep