Could this be a result of too much sun? I have 3 other Coral bells in the same location around a small tree, all getting full sun, but the other 3 are doing fine. Maybe a watering problem?
Yes. These are shade plants, and will not tolerate full sun.
Here is an article that will help:
https://www.gardeningknowhow.com/ornamental/flowers/coral-bells/coral-bells-plant.htm
I wonder if I should move them in the fall? The tree is young, but it would eventually offer some shade....but maybe not till the next season or two.
Thank you for your help! Our coral bells have struggled in this location. The location faces east and gets a mix of sun and shade (sun in the morning and early afternoon depending on the season). All of the coral bells were very healthy in the spring. The location gets more sun in the summer time, which is when the plants die off. The green coral bells are the only ones that have fared ok with the change in seasons. The purple and gold ones have not done well. I did use miracle grow bloom booster (the hose sprayer certain) towards the end of this spring and one of the plants died off shortly thereafter, so I stopped using it at that time. The other plants died off later in the summer. The location is on a slight incline, so I think the water should drain ok.
They may be getting too much sun. Coral bells do best in filtered light or in woodland gardens. Too much water will also sound the death knell. Here are ideal growing conditions:
https://www.gardeningknowhow.com/ornamental/flowers/coral-bells/coral-bells-plant.htm
I planted them about two months ago. Two of them don’t look well. The other one looks much better. Could it be a watering problem? If so, what do I need to do differently?
It could, very well, be overwatering. This will, usually, lead to infection. I would suggest a fungicide and only watering when the soil is dry down to, about, 4 to 6 inches. these articles will help:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/ornamental/flowers/coral-bells