Spilt bird seed can be a messy problem indoors and out; but you can keep your home far from foul with one of two types of seed catchers. The first is called a seed guard or cage skirt, and is designed to fit around the base of your pet's cage; they can be rigid and moulded to fit a particular cage, or flexibly-sized resembling a shower cap. The second kind clips on to the bottom of a hanging feeder and prevents seed from falling onto your lawn. Using a bird feeder seed catcher outdoors is particularly important, because spilt seed can cause brown spots, sprout undesirable plants and attract unsanitary pests such as rats.
Select a durable, washable fabric such as cotton or lightweight denim.
Measure the diameter of the base of a round cage. Cut a round of fabric the diameter of the cage plus 8 inches -- for example, a 12-inch cage requires a 20-inch round. For a square cage, measure the length and width of the base of the bird cage. Add 8 inches to each dimension. Cut a piece of fabric this size.
Wrap an elastic band around the cage horizontally, as if measuring a waist, so that the elastic fits snugly and the ends overlap 1 inch. Cut the elastic.
Hand stitch the elastic to the perimeter or the cloth piece using a basting stitch, a loose straight stitch.
Roll the edge of the round inward twice as if hemming the base of a skirt; the first roll enfolds the elastic, the second encloses the raw edge.
Stitch over the hem to keep it in place with a zigzag stitch.
Select a fine mesh netting or water-permeable fabric.
Cut a piece of cloth 3 inches wider and longer than the feeder. Increase the measured diameter by 3 inches for a round feeder.
Straighten a wire hanger. Bend the wire so that it is proportional to the perimeter of the fabric, but 2 inches smaller -- for example, an 8-inch round of fabric will have a 6-inch wire round. Clip excess wire or bend it around the loop, to double the thickness of the material.
Hem the end of the material to enclose the raw edge. Fold the fabric inward 1/4 inch, twice. Sew over the folded material.
Sew the fabric to the wire frame with a whip or blanket stitch. Insert the needle into the material and pull out, around the wire and into the front. Repeat. Use a water-resistant nautical thread or fishing line.
Cut six to eight, 2-foot lengths of thread. Tie the thread to the wire frame at even intervals.
Tie the thread to the birdfeeder or the tree above the feeder. Ensure the bird seed catcher is positioned under the feeder.
Test the catcher to ensure the seed does not bounce off the material. Make the fabric round larger if it does.
Birdseed catchers for square cages have excess material in the corners. These corners can be mitred for a neater appearance that is flush with the walls of the cage. Put the seed catcher on the cage. Tuck the excess material against the cage, inside of the catcher. Pin the fold closed. Remove and invert the seed catcher. Sew along this fold and trim the excess fabric.