Sinningia ‘Invasion Force’

I am always on the hunt for great, new plants to add to our production at Little Prince of Oregon where I am the director of business development. A few years ago, I was visiting Shinglehouse Nursery in Coos Bay, Oregon, which is owned by plantsman extraordinaire Blair Haynes. Haynes has turned me on to numerous plants over the years, and that day, it was Sinningia ‘Invasion Force’. The genus Sinningia is made up of some 75 species, most of which are native to Brazil and all confined to Central and South America. They belong to the family Gesneriaceae and most species are tuberous herbaceous perennials, which is the case with the hybrid ‘Invasion Force’. Sinningia was named after Wilhelm Sinning (1792-1874) who was a botanist and gardener at the Bonn Botanical Garden associated with the University of Bonn in Bonn, Germany. The hybrid ‘Invasion Force’ was introduced into ornamental horticulture by John Ingram of Floral Horticulture. It was grown from seed from the Gesneriad Society. It was named ‘Invasion Force’ because of its vigor, which is considerable compared to other species of Sinningia. In fact, most species in the genus are not hardy at all and are sold as houseplants, often under the name gloxinia, which is a misnomer dating back to 1817 when a nursery owner mistakenly placed them in the genus Gloxinia. The name gloxinia has persisted in common usage ever since and serves to remind all of us in horticulture that getting names right matters. Sinningia ‘Invasion Force’ thus is commonly called hardy pink gloxinia.

There are a number of hardy Sinningia selections available today. ‘Invasion Force’ is likely the hardiest hybrid, being a solid USDA Zone 7b or perhaps hardier with protection. I’ve had a specimen growing in my landscape for years, and it’s seen 5° F and been unphased. With a presumptuous name like ‘Invasion Force’, it better be hardy, right? The name itself helps sell the plant at the retail level. Also, the fact that it’s a beautiful plant with 2- to 3-inch long pink tubular flowers that attract hummingbirds and pollinators makes it a very desirable plant for gardeners. The fact that it’s a Zone 7 plant should not dissuade those of you in colder climates. It’s a great container plant that can easily be overwintered with a little effort, and it grows fast enough that it’s certainly worthwhile growing as an annual. Despite its name, I would describe it as vigorous, but not “invasive.” Consider growing it in quart to 2-gallon containers. Garden center buyers should certainly be on the lookout for this great plant.