Banking frames hold multiple queens
For short term storage, queen bees can be kept in a banking frame. This is a simple device made by installing a horizontal bar into a regular frame, creating a space that is just large enough to hold your queen cages. The banking frame can be used for up to about three weeks. Queens kept longer than that should be released into a nuc so they can develop normally.
The key to successfully banking queens is to install the frame in a queenless colony or in a queenright colony above a queen excluder. In addition, the frames should be constantly supplied with newly hatched nurse bees to care for the queens. In a queenless colony, you will have to provide a steady supply of ready-to-hatch brood from another source. Individual cages should not contain attendants—just the queen.
Banking is a good option if you are raising queens for sale, if you have an oversupply of queens in your own apiary, or if you are experiencing a long stretch of inclement weather. Remember, though, that the host colony must be strong, well-fed, disease-free, and have a good supply of sealed brood.
The banking frame shown below holds the cages vertically and works fine for a small number of queens. Alternatively, you can build a frame with multiple bars that hold the cages horizontally—sort of like bees in a pantry. The horizontal arrangement can hold many queens but, remember, you must have a supply of newly hatched nurse bees large enough to care for all those queens. Consider the colony strength when deciding how many queens to bank in a single hive.
Even though I made the opening in my banking frames just large enough to hold the queen cages, over time they still sag in the middle. If the cages are too loose they can fall out, especially when you are first installing them in a hive. In a few days they will be firmly propolized in place but, until then, be careful not to drop a cage. Sagging of the horizontal bar can be prevented by fastening the center cage in place, or by installing a vertical support piece.
Also, although queen cages are basically the same size, they differ radically from one manufacturer to the next. If your cages come from multiple sources, you may need to build slightly different frames for each type. Even cages from the same source may be slightly different lengths, so the banking frame often requires a little tinkering to get it right. Banking frames can be made from any size frames, depending on the size of equipment you use—deeps or mediums are the most common, but a shallow frame would work as well.