Easter Lilies are a tough crop for a greenhouse grower. Why are they a tough crop? Because the Monday after Easter, they aren’t worth anything! Timing is very critical on Easter Lilies. You really only have a 1 week window where you can sell them.
Here is a great article on Easter Lilies from Texas A&M. In addition to some great history and other information about the lily, it provides great planting instructions so you can enjoy it for years and years as a perennial in your garden.