Carnations, mums, roses and spray roses are good choices for flowers that are readily available and non-toxic. Ranunculus, peonies, and eucalyptus, while beautiful flowers, are not ones that I would recommend placing on a cake (even when just decorative) as parts of them can cause stomach upset.
Leaves, ferns, rosemary and olive branches are all great choices and pretty easy to get a hold of, perfect for rustic wedding fans! Use small sprigs in order to not create a small forest on top of your cake!
Flowers That Are Safe: Pansies, Lavender, Violas, Violets, Roses, Marigold, Cornflower, Carnations, Chrysanthemums, Day Lily, Hibiscus, Peony, Chamomile, Freesia, Gerber Daisy, Lisianthus, Queen Anne's Lace, Primrose, Sunflowers. Here's a longer list (and what parts of each flower are actually edible!).
In a pinch almost any kind of tape you have around the house will hold floral foam or other anchoring material in place. Narrow strips of electrical tape, masking tape, adhesive tape, freezer tape, or any waterproof vinyl tape will do. Cellophane tape is not a good choice.
Baby's Breath (Gypsophila sp.) has white or pink flowers that have a mild, slightly sweet flavour, perfect for dessert garnishes. The leaves can be tossed in with other greens for a mixed salad, typically to bitter to eat on their own they will add a tangy kick to an otherwise bland salad.
Pop them in the freezer, but make sure they are well covered. For a freezing time of more than a few days. cover your flowers, or they will get freezer burn. From this point, just pipe a small blob of Buttercream, peel your flowers from the backing parchment, and attach your flowers wherever you want them.
While cake layers and frosting can be made in advance, I do not recommend adding fresh flowers to a cake ahead of time. Flowers need water to prevent them from wilting. If they're added to cake more than a day before an event, they can really lose their luster.
Roses are red, violets are blue, but biting a thorn can do damage to you… and your pets. Threat to pets: Although roses do not often cause serious poisoning beyond gastrointestinal upset, there is risk for trauma to the mouth and paws from the thorns. If a large amount is ingested, a bowel obstruction may result.
Can you put fresh flowers on cakes, like roses, peonies, lillies or orchids. Fresh flowers are (mostly) not safe for cakes. A surprising fact is most flowers (especially the most popular for wedding cakes, engagements, etc) are toxic. They contain poisons that can seep or leach into the icing and cake.
Gypsophila or Baby's Breath.(I often suggest my brides go and smell it before they decide they definitely want me to use it!) (Then they come back and ask me for other ideas!!!) Despite the fairy tale romance and 'frothiness' gyp offers, it's toxic if eaten. It can also irritate your nose and cause asthma.
If you want to decorate your cake with flowers, then choosing to use artificial flowers may be the right decorative decision. Silk flowers are beneficial to cake decorators. They do not require watering, will not wilt once placed on the cake and can be bought during any season.
