This is one of those cases where there are two hostas with the same name. One is registered and, therefore, the "official" version of H. 'Festival' while the other is a non-registered plant and needs to be renamed to avoid further confusion.

Alex Malloy of New York registered this sport of H. 'Carnival' in 1998. It grows to a medium size (15 inches high by 36 inches wide) with green foliage that has yellow streaked variegation. Its medium lavender flowers bloom from mid-July into August.

Hosta Helper will call this plant 'Festival' (Malloy).

According to The Hostapedia by Mark Zilis (2009), Paul Aden of New York gave this name to a green seedling with white marginal variegation.

Hosta Helper will call this plant 'Festival' (Aden).