Place flowers where they will not crowd the food
Use the room around the table when the meal needs the center for itself.
Flowers do not have to sit beside the plates to belong to a dinner. A vase near the entry welcomes people before they sit down; a smaller arrangement on a shelf can be seen from the table without occupying it. Moving flowers away from food also gives you more freedom over height and shape.
Choose the view first. Stand where guests enter, then sit at the table and look around. A sideboard directly opposite the seats may be more noticeable than the center of the table. A vase placed behind everybody will have less effect, however carefully it is arranged. Think about where the flowers can actually be enjoyed rather than where an empty surface happens to be.
Keep stems and falling petals clear of eating and serving areas. A spreading branch can look graceful but reach farther than expected as it settles. Turn the arrangement and inspect it from more than one side. Put it in a stable vessel suited to holding water, with protection appropriate to the furniture beneath it.
Strong fragrance can compete with a meal. If a bouquet smells noticeable across the room, move it farther from the dining area or choose a quieter place for it. Guests may have their own sensitivities, so a room does not need several scented arrangements to feel welcoming.
A single bouquet can be divided, but the smaller vessels should have a reason to be where they are. One near the door and one by the seating area may connect those places. Filling every spare surface with a miniature vase can create extra work and leave no room for glasses or bags.
Check the off-table location during the evening as well as before it. A sideboard that later becomes a coffee station may need its vase moved again. Leave a stable alternative surface available, with suitable protection beneath the vessel. Near an entry, keep spreading stems clear of the place where people collect coats and bags. Off-table flowers work best when they accompany the movement through the room without borrowing space from another useful task.