Ageratum houstonianum 'Patina Delft'


Ageratum 'Delft' Yeah, yeah, yeah. Ageratum. It’s got a kind of bluish-purple fuzzy flower and you buy it in six-packs at Home Depot for two bucks and plug it in where something died or got eaten by bugs. Its best attribute is that the flowers seem to last forever. Next plant.

Then, you see Ageratum ‘Patina Delft’ and you stop dead in your tracks and say, ‘wow, where did that come from?’

The aforementioned Ageratum (‘Blue Jay’ and “Blue Ribbon’ for example) is a lowest-common-denominator kind of plant. It flowers reliably and seems immune to both neglect and over-attention. It seeds prolifically and the seeds germinate in just five days. As such, it is sold widely and, to be charitable, is over-used.

But in the AAS Trial Garden, in a container at the back of the area, is an Ageratum unlike anything you’ve ever seen. It’s large, free-flowering, well-branched and, well, it’s gorgeous.

‘Patina Delft’ may be the most accurately named plant cultivar in quite some time. To see it is like seeing one of those delicate pieces of Delftware in an Amsterdam shop window. The large flowers are medium blue fading to white centers; the flowers themselves delicate buttons of floss. The plant forms a mound twelve inches high and more than twelve inches across, although a report on a trial of the plant at the University of Florida described it as achieving a height of 18 inches. The same report also noted that newer flowers emerged just above the older ones, effectively eliminating the need for deadheading.

The plant was developed by Syngenta Seeds which, fittingly, is based in the Netherlands.

Like other Ageratums, Patina Delft wants a minimum of four to six hours a day of sunlight. As an annual, it can be fed repeatedly across the summer to maintain its bloom. Alas, it will die with the first hard frost, leaving behind memories of windmills and wooden shoes.