When is the best time to put out nesting materials for birds?

Kenn and Kimberly: Birds gather materials to line their nests at various times of the year—including fall, when they make shelters for roosting during the winter—but most nest building is in spring and early summer. In your area of New Hampshire, eastern bluebirds and house finches might begin to build nests as early as the end of March, so that would be a good time to start if you have lots of material to offer. If you want to wait for the peak season, start at the end of April.

Female Baltimore orioles use straw, grass, bark, animal fur and other materials to create elaborate hanging nests sometime around May. ADEPT BUILDER