I recently rehabbed an old bluebird house, so that it is more secure and rainproof. I cemented in a galvanized pole and the house is at approximately 6ft. off the ground, next to a fence. It faces kinda North, but that is the best to keep wind and rain from entering the front door. When is the opportune time to put a box up, previously I had heard by March 15th, but that could have been for a different part of the country?
Locate houses in an open, grassy field edge or lawn area away from trees (300 ft or more apart). Place the houses at least 50 feet away from birdfeeders and your main house. Mount the box with the hole facing south approximately 5 feet high. South or East are the best direction to face a nestbox. The further north you are the more important this is. You can read more about that in a previous article: Which Way Do You Face a Birdhouse? http://lansingwbu.blogspot.com/2010/02/which-way-do-you-face-birdhouse.html
Perching areas near to the nestbox like a fence, stakes, small trees, etc. are preferred by bluebirds to give nestling a safe place to make their first flight.
If Tree Swallows compete for the nest site, place another box near the first (15 to 25 feet from the original house). They seem to tolerate overlapping territories of other species, but bluebirds will not nest less than 300 feet from each other. Both swallows and bluebirds are dependent on cavities for nesting, but otherwise they are different in many of their survival strategies. Bluebirds feed on ground-dwelling insects while swallows feed on insects in the air. Given places to nest, they can coexist within an area quite effectively. It may even be beneficial for bluebirds to have swallows nearby to warn them of potential predators or danger.
One important item to mention is that sparrows may try to take over a bluebird nesting box. The only way to help reduce this possibility is to make sure the house is mounted away from the edge of trees or away from human dwellings and to remove the nests before they are complete (a sparrow nest is a sloppy collection of grasses or litter that fills the box, while bluebirds make a neat cup nest and swallows line their nest with feathers). You can also leave the top and side of the nestbox open to make it less desirable until the sparrow relinquishes its claim on that house.
The earlier you can mount your boxes the better. Bluebirds can scout for boxes as early as late January and start build a nest as early as mid-March. Older, established bluebird couples nest first. Younger birds have to court their new mates and find new houses later.
Ultimate Bluebird House http://bit.ly/xeGs0e
Feeding and Raising Bluebirds http://bit.ly/A39dAh
How to Protect My Bluebird House http://bit.ly/zI48Ts
5 Tips to Attract Birds to Nest in your Bird Houses http://bit.ly/yNT6Ye
When is the best time to put up a bird house? http://bit.ly/yAI123
Bluebird House Designs http://bit.ly/w7FWRE