Answer: Based on your description I am not certain what is happening to your geraniums. It is possible that the sickly ones have not rooted out into the soil in the box but instead the roots have stayed in their ball of container mix they came with originally. You could gently dig down and see. If this is what is happening, you can try slicing or unwinding some of the encircling roots and replant. Otherwise I would suggest you consult with your county extension and/or a professionally certified nurseryman to see if they can diagnose the problem for you specifically and then based on that, decide what to do. They may appreciate a sample and/or some photos of the different ailing plants. I'm sorry you are having trouble with them.
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