An open-pollinated seedling of H. 'Subcrocea', Russ O'Harra registered this cultivar in 1991. Forming a small to medium size (9 to 11 inches high) mound, it has slightly rippled foliage and medium purple flowers in July.

According to The Hostapedia by Mark Zilis (2009), "Growing 'Yellow Boa' with a few hours of direct sunlight per day helps retain its bright gold color longer during the growing season. It is slightly brighter than that of 'Feather Boa'..."