What we am doing for our wedding (tight budget too) is I am using hydrangeas (as a nod to my grandma who had them in her garden when I was growing up) but we are not using cut hydrangeas because they are too pricey. We are using small pots of hydrangeas (about $15 at the grocery store here) and I am going to cover the pots with a chocolate brown fabric (our accent color). We are also going to put a little tag on the centerpieces inviting people to take them home and plant them so whenever they see them growing in their garden, they are reminded of our growing love (hope no-one accidently kills them)