Annuals are great companions around young perennials that haven't filled out yet, because for one year they'll bloom with intense flower power that'll give the space a finished look from summer to frost. Mecardonia is a fabulous example of this, excellent frost and heat tolerance means it'll give you a profusion of little bright yellow blooms from May through October. The habit is also useful for massing around perennials or as a filler in a container garden. It's semi-trailing, which is nice for rock gardens and hanging baskets. Mecardonia You may also like: Mecardonia is featured alongside other butterfly-attracting annuals in our Bring on the Butterflies Annual Collection.