I've been using copper wire to hang cork and pots in my vivarium. Copper compounds can be harmful to plants, but is there any danger in using metallic copper for this purpose?
Keep it away from bromeliads. I have been told by commercial growers even water from a brass rain gutter will kill Tillandsias, and care should be taken to choose only copper-free fertilizers for them. Pineapples (Ananas) seem to be indifferent to copper.
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