Take the following:
Two cups (475 ml) rose scented pelargonium leaves
One Cup (240 ml) lavender flowers, preferably still on stem.
One cup (240 ml) lemon-scented herbs
Two cups (475 ml) rose petals
One cup (240 ml) Oakmoss
One cup (240 ml) Larkspur petals
One cup (240 ml) Rosemary leaves
A few small spruce or fir cones.

For a sharper fragrance, mix 50 drops Rose pelargonium oil with 6 tablespoonfuls (40ml)orris root (cut and sifted and add this mixture to the potpourri. Orris root is a fixative, a substance that helps the fragrances last longer.
(Taken from "Scented Geraniums,knowing, growing and enjoying Scented Pelargoniums" Jim Becker and Faye Brawner,Interweave Press.)