Located in New Jersey. Please look into it, advice me what I should do for them. I feel so miserable.
It looks like the type of damage one gets when there is an early snow and the part under the snow survives and the top that is exposed is damaged by the cold and sun that is reflected off the snow. I don't know if our October 29, 2011, snow storm could have done that or not. I haven't seen it here and we got a foot of snow from that storm.
If that is the cause about all you can do is cut off dead portions and wait for the new growth to grow out. (To determine what is dead, scratch the "bark" and if there is a green layer under the bark, it is alive. This is not good for the plant. A better test is to bend the branches to see if they are brittle. If they are brittle, you can do the scratch test to make sure they are dead.)
The wilting of the new growth may be related to the slight drought we are in. In SE PA I haven't had any rain for 2 weeks and had temperatures in the 90s which caused lots of things to wilt. I have had to water a few things. Do not overwater. Deep watering is good but let is soak in. Wet soil will kill rhododendrons. Moist is good, wet is bad.
Here is a link that might be useful: How to care for rhododendrons and azaleas.
Thanks for your advice, rhodyman.
These were planted in March/April 2012. As you mentioned it might be caused from improper weather condition, I can't help. If bugs/fungus have made them sick, I can't bear with it.
One thing you might do is dig it up and inspect the roots. The roots should have been opened up and spread out before planting.
Whether the plant was balled-and-burlapped or potted, make sure that the plant is getting wet. Rhododendron guru Harold Greer noted: "Quite often a plant will get completely dry and then no matter how much water you apply, the rootball will just keep shedding it. The top of the soil may seem wet, and the soil around the plant may even be very wet, but the actual rootball of the plant is bone dry. This is especially true for newly planted rhododendrons, and it is the major reason for failure, or at least less than great success with that new plant. It is hard to believe that a plant can be within mere inches of a sprinkler that has been running for hours and still be dry, yet it can be SO TRUE!"
Most rhododendron and azalea plants sold at nurseries and garden centers are sold in containers or have a root-ball that is covered with burlap. These plants have a potentially serious problem when the roots reach the container and start circling inside the pot. They become pot bound or root bound. These roots must be cut so they don't continue to grow and start strangling other roots. Many apparently healthy plants die when the roots start strangling each other. To prevent this, it is necessary to remove the plant from the container and examine their roots. If the plants appear pot-bound and have a thick, dense mat of fibrous roots along the surface of the root ball, used a knife to make three to six vertical cuts, about 2 inches deep, equally spaced around the sides of the root ball. Then use your hands to gently loosen the roots where cuts were made and pull the roots outward. This process stimulates new root growth and allows water and nutrients to penetrate into the root mass. If the roots are not pot-bound, it is not necessary to slice them with a knife, but it is beneficial to loosen and pull them outward with your hands. When working with roots, make sure the plant is thoroughly watered. Any roots that dry out will die.
Thank you! Rhodyman.
You are right. I looked into the roots. They were all tangled, were dry.