..but in answer to your question;

Yes, they're real.
(I attend many flower & landscape exhibitions.)

Like the "Sugar Art" competitions I participate in
(My specialty is "Gingerbread"
You're allowed a VERY Low Percentage
of non-edible components in your presentation.)

Aside from the hidden Frame Work and Growing
Medium, ...the same applies to HortiSculptures.
"...or am I a butterfly dreaming she's a woman?"