A sport of H. 'Undulata' from Japan, this large size plant has lightly rippled, smooth textured foliage of average substance. The fast growing mound is 21 inches high and 47 inches wide with elliptic to broadly elliptic leaves. Pale lavender, funnel shaped flowers bloom in July. 'Undulata Erromena' was registered by the The American Hosta Society in 1987 as "parentage unknown".

According to The Hostapedia by Mark Zilis (2009), "...surprised at how much larger it becomes than all the other Undulatas...the most durable plant of this group..."

This cultivar has been awarded the Royal Horticultural Society's Award of Garden Merit in the UK. It may have been sold at one time under the name Mackwoods No. 3.

 In Latin, the word "erromena" means vigorous growth.

An article about H. 'Undulata' and its origins by Bob Solberg in The Hosta Journal (1996 Vol. 27 No. 1) states that, "H. 'Undulata Erromena' is a garden sport, first originated in Holland and introduced in 1867 by von Siebold. It is not found in the wild of Japan. H. 'Undulata' is not a sport of it...While the data presented here strongly support these conclusions, they do not provide absolute proof. DNA testing of these cultivars would prove very interesting."