Camellia Bush Dying
The flowers are wilted or never bloom out all the way, have brown petals around the flower, but not inside. Some of the leaves have yellow blotches with small, black raised spots along the undersides. The entire bush is sparce this year, but the one next to it is doing fine. Should I get rid of it (4 feet high), prune it or spray it??
chueyy, please don't apply herbicide to your camellia as it may kill it. Sometimes blooms on some peony, camellia and heirloom rose varieties, especially those with many petals, have difficulty in full expansion. This could be caused by several things. Rain can "glue" the petals together, or cause water marks on the blooms. Too much or too little water could be stressing the plant, therefore affecting the blooms. Mites or thrips could be on the plant, they can be seen with a powerful magnifying glass. If it is thrips, the blooms will definately be affected. If it is a mite, yes, you will have to use a miticide...insecticides will not work on mites. Your leaf problem could be caused by either an insect or disease, in either case there are sprays that work to control it.
The following article might help answer some questions: https://www.gardeningknowhow.com/ornamental/flowers/camellia/camellia-flowers-not-opening.htm
At the beginning and end of the article is a search window. If you enter the word, camellia, several more article links concerning camellia will come up and you will access to a ton of information.
I would spray it with pesticides, selective herbicides, and fungicides. Some kind of fertilization issue jumps out at me but I can not be sure. Has the bush ever been healthy? If you could provide pictures of the problem it would considerably help diagnose this problem. Do not give up on the plant, remember it is a living thing and can recover with a little love and patience. Good Luck and Happy Growing!