How high should a Bluebird feeder be
Bluebirds will feel safe at a bird feeder when its some distance off the ground, yet the presence of pets or predators near by will prevent them feeding all together.
How high should bird feeders intended to attract Bluebirds be, is the same as any type of bird feeder in use. Suspend or place a mealworm-filled feeder or dish up to 4 feet minimum off the ground - with 5-6 feet being that little more safer. Bluebirds must be kept out of reach of predators or pests.
How high to hang a bird feeder that is filled with dried mealworms, and therefore intended to feed Bluebirds as its their favorite bird feed, must continue to rely on a place that is some distance off the ground.
Remember, stray cats will want to kill the Bluebirds for fun, thus cats will lay in wait for their opportunity. Which will be made easy if the bird feeder is hung only a couple of feet up - or placed on a high but still accessible to cats or predators' surface.
Suspending a Bluebird feeder at the recommended 4 feet minimum, isn't safe at all when it comes to cats; they can jump quite high as it happens yet would on occasions catch Bluebirds out. I will always shoot for as high as 5-6 feet if you can.
Bird feeder pole bracket setting is usually 4 feet or less, yet the bird feeder can hang even lower if its the long tubular-like bird feeder.
I would provide an open bird feeder tray to feed dried mealworms to Bluebirds - which you can now also put live mealworms in - as a bird feeder tray won't drop close to the ground, as its essentially a flat bottomed dish that will provide no additional length.
You will probably hang a bird feeder on a bird feeder pole to attract Bluebirds, which is perfectly fine, and safer if pests or predators frequent an available tree in your yard.
Do hang or place a Bluebird feeder as high as you can when cats or other predators are about in your yard. Bluebirds may still feed with these animals present, but they won't really bother if they are forced to feed within reach of dangerous animals.
Never below 4 feet on pole
To keep the Bluebirds intended bird feeders out of reach of ground predators and pests, you should never suspend or place a bird feeder below 4 feet at the very minimum.
A rule which will apply to suspending all hanging bird feeders really, thus it won't be any different when its a mealworm feeder intended to attract Bluebirds.
When it comes to how high should a Bluebird specific bird feeder should be - simply depend on the default setting on a bird feeder pole. Bird feeder poles provide a reliable distance off the ground... thus there's no need to be concerned about how high again.
Let's assume for a moment you are utilizing a suspended bird feeder tray, which is usually hung with the use of chains.
Well, this type of bird feeder will in fact provide no additional alterations on your part, as the shallow depth of this bird feeder won't drop any further to the ground - which can be unintended but a deadly oversight on your part.
What I mean by that is a long seed or peanut bird feeder for example, will drop an additional foot or so, because they are a long tubular-like bird feeder.
Bird feeder trays or dishes will not extend the length of this type bird feeder dish, below what would be the danger zone, close to the ground.
Safer at 5-6 feet high
With a 4 foot minimum distance off the ground in an effort to protect Bluebirds from pests or predators - including the always troublesome pet cats - to go higher than 4 feet is absolutely recommended.
In fact, there are no hard or fast rules how high a bird feeder can be hung, providing its found in a lit up area.
Bird feeder poles still remain the number one place to locate a Bluebird feeder, although realistically it isn't going to do well to defend against predators if they do indeed visit your yard on a regular basis.
What you can do then is make your bird feeder pole higher by sinking it into an additional hallow pole, to raise the Bluebird feeder to as much as 5 to 6 feet.
Six feet or higher can be achieved when still depending on a bird feeding station pole.
Where else a feeder can go that is intended to attract Bluebirds, is to hang it off any available high branch if there is a suitable tree in your yard.
Shy feeder-bird requires space
While Bluebirds are bird feeder birds like your common Finches or some Warblers, they would prefer a bit of space of their own.
With that in mind, there's no harm in suspending a Bluebird feeder all on its own.
Space available in the yard to hang a bird feeder can be short, which I understand, yet when you do find a place to hang the bird feeder, preferably filled with dried mealworms, hang or place it in an isolated area.
Not so hidden the Bluebirds feeders are suspended in an out of the way, undisturbed location, where the bird feeder will actually end up going unused.
How most of us attract Bluebirds into our yards, is with a wide open lawn that will provide the earthworms and insects Bluebirds scoop down to grab. When a suitable lawn isn't available, in the end a Bluebird-intended feeder must be used.
I would still hang a mealworm-filled bird feeder tray along with other bird feeders on a bird feeder pole or tree branch - as there's no guarantee a Bluebird will in fact want to feed alone.
Although it can help to provide mealworms separately in a dish or to scatter them on the ground, so the Bluebirds can avoid use of a classic bird feeder; a device that Bluebirds often avoid unless its an open top dish or platform.
Summary
Much like a bird feeder made to store suet, seeds or nuts, none of which must really be hung or placed below 4 feet if you can help it.
Backyards of today frequently receive visitation by stray animals or the neighbors cats; cats of course being the biggest killer of our wild birds. With that, some distance off the ground can at least provide Bluebirds some protection, however futile it might be.
Cats regularly catch wild birds out of thin air, so to will they pounce on birds, and therefore Mountain, Western or Eastern Bluebirds, eating at feeders.
Four feet isn't all that high, but it is the most common default setting on any bird feeding station, or Shepherd's hook pole available.
If you can, go out of your way to buy a bird feeding station pole that is promoted as extra long, or indeed provides a telescoping pole that will extend up to 7-8 maximum.
When that doesn't work, there are solutions to extending a short bird feeder pole, into a long one that is sure to protect Bluebirds at feeders.