Hi there, Heather!
Epcot is so beautiful during the Flower and Garden Festival (F&G); the weather is warm and breezy, the smells of blooms mingle with the sweetness of the funnel cakes in the air ... ahhh. And in 2012, F&G is scheduled for March 07 - May 20.
The commercial-grade play structures (which my children greatly enjoyed!) are sponsored by a company called Landscape Structures, Incorporated. According to their Web site, they have "partnered with Epcot® and its preeminent landscape architects to create magical play environments for children of all ages at the Epcot International Flower & Garden Festival in Lake Buena Vista, Fla." since 2001.
While there is currently no
public sponsorship agreement between LSI and Epcot, there does not seem to be much reason to doubt the continuing relationship between the two. I spoke with a Cast Member at Epcot who told me that the structures were so popular, he could not foresee an end to having them available. That's not an official answer, but it's a likely supposition.
Your best bet is to check the
Disney Parks Blog for updates as F&G draws closer -- and, of course, the
official site for F&G as well.
Have a great time as you stop and smell the roses!
See you later, celebrator,
-Deborah B.