| They are hydroponic rocks and you can grow a Cattleya either as true hydroponic with a clay saucer, or as I do just use the rocks for its good drainage and water it like in was in bark but a little more often.
They have no organic matter so they need to be fertilized regular. Mine are outside in the rain so they get flushed naturally. If not flush yours by running water over it for 15-20 minutes once about every 3-4 months.
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jerry  |