I am making a buttercream iced wedding cake with silk flowers can I stick the ends of the florist tape directly into the cake??
The ends of the florist tape?? Usually silk flowers don't have florist tape--are you wrapping the stems of the flowers with florist tape?? Yes you can stick that in there I think. But you can slip the stems into a straw to protect the cake too.
The idea here is the cleanliness of the silks and the tendency of the wires inside the stems to rust inside the moist cake. So that's the deal on that.
Usually you find the florist tape used on hand made flowers.
I wouldn't stick anything not food-safe into a cake. I would definitely follow k8memphis' suggestion to insert straws into the cake first in order to sheath the stems. Otherwise, wrap them in plastic wrap first.
I know there are of plastic deco's that are always stuck in cakes but I too would worry about the wire part inside the floral stems, not to mention if there is actually floral tape that you asked about, if so then between the paper tape and adhesive, can't imagine that is good for your food!