Frank Giglia said that some growers in South Florida will use the blue shade cloth to keep the plants growth compact and it delays the blooming, the buds will form but are reluctant to bloom while under the blue cloth.
Then after they receive an order, they put the plants under red shade cloth to initiate blooming. If the order is delayed they put it back under the blue cloth to stall the blooming process.
He said they can produce multiple "batches" of blooming plants from the same crop so the retailers have a constant supply of plants that are in fresh bloom.
I would love to see a university do a study of this over here in the states.
JT