Overwatering will definitely produce yellow leaves. Given the sequence you outline above, I would say too much water is the problem. New plants sometimes need more water to get going than established plants need, but deep watering won't help newer plants since they do not have deep roots. Just let them dry out a bit for now.

They must be doing all right in general since you've had some blooms. Deadhead those spent blooms--just snap off the old bloom head. That will encourage your rose to work on producing new growth.

If you are not sure whether the soil is dry or not, just poke a finger into the soil. If it is moist several inches down, it is probably doing all right.

In about a week, your roses will probably perk up. Nothing fatal probably happened unless you absolutely drowned them--I don't think you did.

Happy rosing,
Kate

I would think about poor drainage first. The light green leaves and the dying yellow ones in your photo are characteristic of both the low oxygen and the low nitrogen found in poorly drained soils. If you dig down with your hand, is the soil sopping wet or just damp? Drainage is more a matter of location than anything else. Are your roses located in a low spot or are they on the upper parts of sloping ground?

Thanks for the input.

It may be a drainage problem. I just checked the soil and its still pretty moist, not sopping wet but more moist than I think it should be after 3 days of high heat with no rain. They are located on the top part of a slope.

Is there anything I can add to the soil to help? Would any fertilzer help? I placed Bayer Rose Care granular fertilizer around it when I planted it.

There are soil conditioners that contain gypsum that will take some time, but will effectively break up the clays, improve drainage, without totally loosing the moisture retention character of the clays.

The classic symptom of waterlogging is pale green leaves with yellow veins, appearing first at the bottom end of shoots and moving upward. The leaves go limp and drop. I'm not sure if that's your problem.

You need to know how much you are watering, as opposed to "a good soaking." Roses will use around an inch of water a week, or a bit more during your hottest weeks. Use a rain gauge and measure the output of your drip. Two gallons or 1/2" every three days might be appropriate for small and medium-sized plants in summer, less in spring or fall. IMO, new plants from pots need to be watered twice a week because most of the roots are still "in the pot." I start them off with water every two days.

As Ann says, gypsum is a good amendment for acid clay soils, if that is what you have.