
Certified GKH Gardening Expert
This will depend on many factors. I will need to know which bulbs you plan to plant, what area you are located in (climate zone), and several other factors. Many bulbs will require a certain set of conditions to flower. When you combine many bbulbs of different plant, then those times will vary even greater, as many other them will have different requirements to flower. I would suggest sticking to one type of bulb, unless you have a multi segment greenhouse that you can, carefully, control each plants' environment individually. Otherwise, it could be best just buying bulbs already in flower from someone with those kinds of facilities.
On the other hand, if it is just one flower type, and it happens to thrive in your conditions, then all you have to look for is a plant that will naturally flower at that time in your area.