How to Use Floral Foam

Man placing irises in floral foam

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Floral foam, that green Styrofoam-y looking substance you see in craft stores and at the bottom of your gift flower arrangement, is one of the top ten most important tools florists use to create their professional-looking designs. The foam is inexpensive, and, let’s face it, fun to touch and work with, but it can be frustrating to get the maximum performance from this simple looking substance. Learn how to make florist foam enhance your floral arrangements.

Shapes and Colors

Floral foam comes in many shapes that save you time on cutting. Bricks, spheres, cones, and wreaths are the most common forms available, but you can also find inspiration in novelty shapes like hearts, footballs, or even high-heeled shoes. If you can’t find the shape you want to prepare your design, consider buying a floral foam sheet that you can cut into a monogram or symbol. You can purchase floral foam mounted on a base for table centerpieces, or wrapped in netting to facilitate hanging arrangements like pomanders.

Although green is the standard color for floral foam, you can find rainbow floral foam in brilliant hues ranging from bright yellow to fuchsia. Rainbow floral foam provides a way to add embellishment to topiaries or centerpieces for weddings or holidays when you need an extra pop of color.


Floral foam usually doesn’t come with detailed instructions, and this is the beginning of the end for someone who hasn’t worked with the foam before. You must resist the temptation to crush or press the delicate foam in its dry state. The air-filled cells crush easily, and the water-holding capabilities of the foam are destroyed when the foam is compacted.

You must thoroughly hydrate your floral foam before working with this material. You can use tap water or a prepared solution of cut flower preservative to accomplish this. There’s no need to weigh the foam down or otherwise attempt to submerge it; the foam will gradually sink in a container of water as it fully hydrates. This can take five minutes or an hour, depending on the size of your foam piece. Condition your flowers when the foam is almost hydrated; do not allow the foam to dry out before cutting it or inserting stems.

Use in Vases and Containers

The foam brick you bought probably won’t fit into your container or vase; you must carefully cut it to fit. If your container is shallow, the surface of the foam should be a few inches taller than the dish. This creates a full look and will give the illusion of more flowers in a small space. Secure the foam in a small dish with a few strips of clear waterproof floral tape.

For deep containers and vases, shave off the four corners of your brick just enough to gain clearance into the vase. It isn’t necessary to cut the brick into a perfect circular shape to match the opening of the container. For large containers, you don’t need to fill the entire container with floral foam. You can use a filler in the bottom of the vase, like styrofoam peanuts, sand, or craft stones.

Inserting Flowers

If your flowers have sturdy stems, you can cut them at an angle and plunge them into the hydrated foam. Do not pre-poke holes in the foam for easier insertion of weak flower stems. This will result in poor stem-to-foam contact, causing flowers to wilt from lack of water. For weak stems, wire the stems to a wooden florist pick and insert the pick and stem together. If you need to reposition the stem in the floral foam, pull it out and make a fresh cut in the stem to eliminate life-shortening air bubbles.