Dispose of sick plants
Sick plants that have been received, should not be disposed of on the compost. You can usually do all the organic waste on the compost heap. But if you have plants that have been attacked by pests or a plant disease, you should dispose of them separately.
Most compost piles do not get hot enough to completely eliminate viruses and germs.
If you let the sick plants rot on the compost heap, you drag yourself back with the new earth the pests or pathogens.