Here are a few things that have worked over the years to attract lots of birds to my yard. I've lived in shady yards with lots of trees, yards with wide open spaces in the city, shady city lots and out in the county with both trees and fields. the same methods have worked in all places.
It also helps to have a source of water. A bird bath will work for this or even a big flower pot saucer filled with water near the feeder. I have my little puddle that I recently posted about. Water is not totally necessary, birds will manage to find water but I have noticed they stay around longer if there is water nearby.
Some sort of protection helps. Bushes, nearby trees, etc. We don't want the cats to get the birds! Besides if there is cover this also provides nesting places for them to raise their babies. Nothing is more fun than watching mama wren trying to keep up with and feed a nest of fledglings.
Now about what to feed. DO NOT WASTE YOUR MONEY ON WILD BIRD SEED! It ends up mostly uneaten on the ground. Buy black oil sunflower seeds. Nearly all seed eaters love them. In summer we sometimes by niger seed for the goldfinches but they will eat the sunflower seeds too and don't make nearly as big a mess. Speaking of mess. You will have dropped bird seed and hulls under your feeder. The ground feeding birds like Rufus Sided Towhee, Doves and others eat what the other birds drop. We rarely clean this up. It keeps weeds from growing under the feeder. If you use wild bird seed, you will have weeds. Sunflowers are usually treated to deter sprouting and this does not harm the birds.
Suet will attract Woodpeckers. We love watching these beautiful birds. They rarely eat at our feeders because the squirrel proof ones are a little hard for them to access. Sometimes they eat on the ground and on snowy days I put sunflower seeds our in pie pans, etc so they can get to them. Woodpeckers love suet! Here is a link to my post about suet feeders...We always have suet even in summer. BTW: feed your birds all year. They need to eat in summer too and it helps with the baby birds when they hatch. see The Baby Wren Saga
Providing nesting boxes and bird houses goes a long way toward attracting more birds, especially Bluebirds and wrens. See my birdhouse posts for more info on that.
Another thing we do is feed meal worms to our birds. Every one of them love meal worms! I feed these near the house so we can watch from the window. Here's another post about that Feed The Birds
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