An arch that includes an array of flowers can make a lovely addition to a wedding, outdoor party or other event. Generally, arches are fashioned with wood or metal. While the prospect of attaching a flower arrangement to the arch can seem daunting, it's relatively easy, especially if you're prepared to build the arrangement on site and have the right supplies in hand.

Secure the arch to the site where you would like it positioned during the wedding, party or other event. Position a ladder next to the arch as you're likely to need it when you're creating the arrangement.

Place an assortment of freshly cut flowers and greens in a water-filled bucket where they can remain hydrated as you assemble the floral arrangement. Submerge a brick of plastic-backed floral foam in a water-filled bucket until it is completely saturated. Choose floral foam bricks that have a green plastic backing on one side.

Remove the floral foam brick from the water. Determine where on the arch you want to position the floral arrangement. Typically, an arch arrangement is centered at the top of the arch and faces outward so everyone can see it.

Secure the brick of floral foam to the arch using floral wire or cable ties. You'll probably want to stand on the ladder to do this and to complete the rest of floral arrangement.

Pick up a piece of greenery. Trim its stem to your desired length using a floral knife. Insert the greenery into the floral foam as desired, using it to create the foundation of the arrangement. Let long pieces of greenery drape down from the bottom and sides of the floral foam for a graceful effect. The advantage of creating the arrangement on site is that you can tailor it specifically to echo and flatter the shape and dimensions of the arch.

Insert your flowers into the floral foam. Echo the shape of the greenery with the flowers. Drape longer flower stems from the bottom and sides for an arch-inspired shape.

Make sure the floral foam, floral foam backing and floral wire or cable ties are all completely hidden by flowers and greenery. Step down from the ladder and away from the arch to view the arrangement from a distance.