No, you generally should not put bird seed in a bird house. Bird houses are designed as nesting sites, not feeders, and most cavity-nesting birds prefer a clean, empty box with just the nesting material they bring themselves. Adding seed can attract pests, create unsanitary conditions, and even discourage the very birds you want to host.
Why Bird Houses Are Not Feeders
A bird house mimics a natural tree cavity—a protected hollow where a bird builds a nest and raises young. In the wild, a cavity doesn’t come pre-stocked with food. Parent birds forage outside and bring food to the nestlings. If you fill the floor with seed, it serves no nutritional purpose and can actually cause problems:
- Seed attracts house sparrows, starlings, mice, rats, squirrels, and insects—none of which you want inside a nest box.
- Accumulated seed and droppings create a damp, moldy environment that can harbor bacteria and fungi harmful to chicks.
- Many cavity nesters, such as bluebirds, chickadees, and wrens, are insect-eaters during breeding season; they won’t eat the seed you leave, and the clutter may make them reject the box.
What a Bird House Should Contain
For most songbirds, the ideal bird house is empty except for whatever the birds themselves bring in. Different species build different nests:
- Bluebirds and tree swallows build cup nests of grass, pine needles, and sometimes feathers.
- Chickadees and titmice line their nests with moss, fur, and soft plant fibers.
- Woodpeckers, which excavate their own cavities, may use a nest box but typically leave it bare or add just a few wood chips.
- Wrens often add twigs and may fill several boxes with “dummy nests” before choosing one.
You can help by leaving a few natural materials nearby—like dried grass clippings, pet fur (from brushing, not chemical-treated), or small twigs—but never place them inside the box. Birds prefer to do their own arranging.
When Seed Might Be Acceptable
There is one narrow exception: some people use bird houses as winter roosting boxes. In cold weather, birds like bluebirds, chickadees, and wrens may huddle inside a box to stay warm. In that case, a thin layer of dry grass or wood shavings (not seed) can provide insulation. Seed still isn’t needed—the birds will leave at dawn to find food. If you want to offer food in winter, place a separate feeder nearby, not inside the roost box.
How to Choose and Place a Bird House
If you’re setting up a bird house for nesting, choose one with the right entrance hole size for your target species—too large lets in predators and competitors. Mount it at the recommended height for that species (bluebirds prefer about five to six feet off the ground; chickadees often nest higher). Face the entrance away from prevailing winds and direct afternoon sun. Avoid placing multiple houses too close together, as many cavity nesters are territorial.
Make sure the box has drainage holes in the floor and ventilation near the top. A hinged or removable side makes cleaning easier after the breeding season.
Cleaning and Maintenance
After each brood fledges (leaves the nest), remove the old nest and debris. Wear gloves and discard the material away from the house. Rinse the interior with a mild bleach solution (one part bleach to nine parts water), then let it dry completely before closing. Do this between broods and again in late summer or early fall. A clean box reduces parasite loads and encourages return visits next year.
Common Problems and Misconceptions
A frequent mistake is assuming birds will eat from the house like a feeder. They won’t. Another is placing a feeder too close to a nest box—this attracts predators and can lead to repeated disturbance. Also, many people worry that leaving old nests will keep birds away; in reality, most birds prefer a clean box, but they will sometimes reuse a site if the old nest is removed.
If you see wasps, ants, or mites in the box, clean it thoroughly and consider applying a non-toxic insect repellent around the pole (not inside). Never use pesticides inside the box.
Alternatives: Feeders and Nesting Material
If your goal is to feed birds, use a separate bird feeder. Tube feeders, hopper feeders, and platform feeders are designed to dispense seed safely. Offer a mix of sunflower seeds, millet, and cracked corn in winter; suet or mealworms attract insect-eaters during breeding season. For nesting material, you can hang a mesh bag with natural fibers, pet fur, or short lengths of cotton string in spring—but keep it away from the nest box entrance.
Frequently Asked Questions
Will birds use a bird house with seed inside? Some may, but they’ll likely remove the seed or build on top of it. The clutter increases the risk of disease and pests, so it’s better to leave the box empty.
What should I put in a bird house to attract birds? Nothing. A clean, empty box with the correct entrance hole size is the best attractant. Place it in suitable habitat away from heavy traffic.
Do birds bring their own nesting material? Yes, most cavity nesters gather grass, twigs, moss, feathers, and fur. You can offer loose material nearby, but don’t stuff it inside.
Can I put bird seed in a roosting box in winter? No—seed can spoil and attract pests. Use dry grass or wood shavings for insulation, and provide seed in a separate feeder.
How often should I clean a bird house? Clean after each brood fledges and again in late summer. Use a mild bleach solution and let it dry completely.
What if I see mold or insects in the house? Remove the nest, clean the box, and improve ventilation. Avoid using chemicals inside; instead, relocate the box if pests persist.