| Firm or crisp and white, green, creamish, or brownish is good. Leave these roots as they are.
Soft or mushy and grey, dark brown, or black is bad. These are probably rotten and should be removed.
Please note that it also depends on what kind of orchid you are looking at. For example, some Coelogyne have thin, hard, dark brown roots which for them are perfectly healthy.
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