Measure the diameter of a topiary wreath frame. Cut a pantyhose leg to the length of the topiary diameter.
Fill the pantyhose leg with potting soil. Tie the opening of the pantyhose leg in a knot.
Thread the soil-filled pantyhose leg into the inside of a wreath frame, like a tube inside a tire.
Stuff Spanish moss into the wreath frame so it covers and holds the stuffed pantyhose in place.
Make three to four slits into the pantyhose, evenly spaced around the wreath. Transplant ivy starters or seedlings into the slits.
Hang the wreath in partial light and in a cool area.
Spray the wreath thoroughly with water to saturate the moss and soil. Spray the wreath periodically to keep the soil moist. Do not allow the soil to become soggy or dry out.
Tie the ivy branches to the wreath frame with string or wire as they grow to maintain the circular shape of the topiary. After the wreath fills, trim excessive or wild growth to keep the wreath from becoming overgrown.