Your plants will train to expect certain conditions and will perform accordingly. Never feed a sick plant, never exceed the recommended strength of a fertilizer, and never feed a plant that is dormant. Mature plants prefer a medium grade fir bark, while small plants, which need more moisture retention, prefer a fine grade. Repot when new growth is 2-3 inches tall. Mature plants should not fully dry out.
Improper humidity can cause bud drop.
Use pebble trays where possible. Do not use fertilizers containing urea on orchids, because urea requires breakdown by soil microbes that aren't generally in orchid media. Toxic salts can build up and damage roots. You should use both inorganic and organic fertilizers, and alternate your brands of inorganic fertilizers regularly to offer your plants the widest possible array of trace nutrients. To prepare your own organic fertilizers, place about 3 handfuls of poultry manure in a 3-5 gallon bucket.