Fill a 2-gallon basket with fresh rose petals. Harvest the rose petals just after the flowers open fully. Don't press the petals into the basket; you want them to be fluffy and undamaged. Sort out any thorns, leaves, rose hips or insects you find.
Place your petals in an enamel or steel simmering pan and cover the petals with water. Simmer until the rose petals wilt and look like red, cooked spinach. You may also use a cast iron pan if you want dark beads, but stay away from aluminum. The rose petals will react and ruin both the petals and the pan.
Allow the wilted petals to cool for about an hour. Pour the mix into a blender and liquefy until thick, smooth and wine-dark. The mix should stick easily to a spoon if you gently touch it to the mix.
Pour the pulp back into your simmering pot. Add enough water to cover the rose pulp and simmer for about three hours. Do not boil; you'll cook the roses and they'll dry out. Keep the simmering steady.
Allow the pulp to cool overnight. It should dry out enough that it becomes doughlike in consistency. Pinch out little bits of the dough and roll them between your palms to make 58 beads about ¼ inch in diameter. This should be enough for 5 pater beads and 53 Hail Mary beads, the usual quantities on a Catholic rosary.
Let the beads harden for about 24 hours. Gently push them onto a bamboo skewer to create holes. At this stage, they should have a leathery exterior but still be soft in the center. Let the beads harden for an additional 48 hours before stringing.