Finished! This fall centerpiece would be beautiful as wedding or shower arrangements for your tables. Keep in mind, however, that fresh pumpkins will not last as long as the flowers - you may have to transfer into another container after the pumpkin begins to get soft.
I like to guard against possible table stains by placing a clear or colorful plate under the pumpkin.
Check your pumpkin daily for spoilage and add water to the flower foam to replace what is drawn up by the flowers.
I always spray my finished flower designs with a flower sealant such as Finishing Touch. It seals in the moisture. This is especially important around fall time, since furnaces suck moisture out of the air (and out of your flower petals!)