When it comes to BYDs—Big Yellow Daisies—gardeners have no shortage of choices. The trouble is, the flowers, whether they belong to a coreopsis, a helianthus, or a rudbeckia, tend to be much of a muchness. Also, many don’t get going until August (that “composite-ridden month,” as Louise Beebe Wilder called it), at which point there’s a glut of them. Heliopsis helianthoides, a species that occurs widely throughout the eastern half of the United States and southern Canada, bucks the trend by beginning to bloom in June and continuing for many weeks, but in other respects it’s a typical bold, brassy, and not terribly exciting BYD. Which is why the selection ‘Prairie Sunset’, made by renowned plantsman Neill Diboll, of Prairie Nursery in Westfield, Wisconsin, comes as such a refreshing surprise. Whereas the typical wild species has somewhat open, lax, monochrome flowers, ‘Prairie Sunset’ has trim, rounded, two-inch flowers with an attractive orange-brown ring near the center. The flowers are borne on long branching stems that grow from four to six feet tall, although the plant itself is svelte and airy, which makes it easy to tuck in among bulkier plants at the back of the border. The stems themselves are a striking blackish purple, and the undersides of the leaves are purple as well. Against a dark background, the flowers almost seem suspended in air.
‘Prairie Sunset’ isn’t the only heliopsis cultivar around, but, to my eye at least, it is easily the most pleasing. The others are mainly German selections of H. helianthoides var. scabra, and while they share ‘Prairie Sunset’s long bloom period and strong consitution, they lack its delicacy (especially the dumpy doubles) and dramatic stem color. All heliopsis, by the way, are excellent for cutting.
Provided you can give it full sun and soil that isn’t waterlogged, ‘Prairie Sunset’ with thrive. It is also quite drought tolerant once established, although flowering will be more prolific if moisture isn’t curtailed too drastically. The only pests I’ve noticed were some exotic-looking, raspberry-pink aphids, but a squirt of insecticidal soap made short work of them.
In my sunny border, I’ve got ‘Prairie Sunset’ tucked into a fairly tight spot between dark blue delphiniums. It picks up the yellows and oranges of some Asiatic lilies and hemerocallis in the foreground without calling too much attention to itself, which is just the effect I wanted. Mae West had a point when she said, “Too much of a good thing can be wonderful,” but with BYDs, understatement wins the day.
A version of this article first appeared in Horticulture magazine, vol. 100, no. 6 (November/December 2003).