I was recently asked to make two large flower arrangements for a church's 8th grade graduation service. The students picked bright orange and bright green (!!!) Gerbera daisies as their class flowers, so the arrangements would center around those flowers.
1. THINK IN 2D: Regular tabletop arrangements need to be beautiful from all angles; this kind of arrangement will only be seen from one angle which changes the way you approach arranging the flowers. Height and width are important for impact; depth isn't as crucial.
2. FACTOR IN SCALE: This is especially important if you are making flowers for a church altar. The space is large and most people will be seeing the flowers from far away. Tiny flowers and small arrangements don't work as well.
3. HAVE A PLAN: While you are picking out silks at the store, hold them in your hand or lay them out on the floor to get an idea of how they will look after you have arranged them. This will help to prevent you from buying too many (or too few) stems.
4. KEEP IT GREEN: As pretty as the focus flowers may be, large flower arrangements don't look right without filler flowers and greenery.
5. MIRROR, MIRROR: If you are making two arrangements, it is best to make them mirror images of each other. To do this easily, work on both arrangements simultaneously. Place a flower in one arrangement, then place the same kind of flower in the other arrangement.
6. STEP AWAY: Since the scale of these arrangements is bigger than usual bouquets, take a minute now and then to step back and look at the whole picture.
To make a large silk flower arrangment, you will need:
several stems of silk flowers
vase or container
floral wire and/or tape
floral or wire cutters
hot glue gun (optional)