To throw rice on the freshly married couple is used after they got married.
Rice means fertility for them for lots of kids.
Nowadays some places do not allow the rice anymore as it attracts birds and rats to eat the grains of rice. It also leaves stains on the dark jacket of the groom. So better use natural bio-rice.
In Europe in the last centuries rice was quite expensive, so people used peas and millet (remember Cinderella ?).
Instead of rice why not use coriandoli, small paper pieces. There are real canons of them available.
Quite cute are the wedding bubbles, which can be found in all wedding-adapted shapes.
Or rose petals that can be in the same color as all other decorationOr rose petals that can be in the same color as all other decoration.
Or the classical white balloons.
A moment of joy is created by letting fly white doves.
In Italy they pasta into the bride and groom. This I remember very well when my niece throw pasta at me, quite big pieces, so that almost hurt me.
In Indonesia bride and groom get a garland of paper around their necks.
Or in Hawaii you get the famous necklaces made of fresh flowers.
The Indians from America let fly butterflies. They say that the butterflies do take all unspoken wishes into the sky. Very important is not to speak out loud.
Enjoy planning your wedding,
Britta, Creative Wedding