A tradition in many congregations
In a lot of Muskogee churches, the flowers at the front on Sunday morning are given by a member. The bulletin might say, The altar flowers are given in loving memory of a parent, or in honor of a couple's anniversary.
Each church has its own way of doing this. Some keep a sign-up sheet, use a regular florist or need flowers by a certain time on Saturday. Check with the church office before ordering, then give the florist the details.
Seasons matter in church. Easter lilies, Christmas poinsettias and red flowers for Pentecost are common. See Easter flowers and poinsettias.