Plant of the week: Southern Red Trillium (T. sulcatum) or is it Trillium erectum or is it T. simile?

Of all the spring wildflowers the trilliums are perhaps the showiest of them all and Kentucky is privileged to have a variety of species including large white-flowered (grandiflorum), Nodding or bent (flexipes), Yellow (luteum), Sessile (sessile), prairie (recurvatum), Ozark (pusillum), snow (nivale), painted (undulatum), and sweet Betsy (cuneatum), and the topic of this post, Southern Red (T. sulcatum) and Stinking Benjamin (erectum).  There is no doubt that the genus trillium is a southeastern genera and nationwide there are over 40 species known to science.  Of that number, the one that perhaps Kentucky can claim as the most Kentucky of the species is Southern Red Trillium (T. sulcatum) as the primary range for this species is the Cumberland Plateau.  This species can be quite difficult to tell apart from Stinking Benjamin or Red Trillium as they both have red, white, or cream colored flowers, they both have a dark ovary in the center and they grow side by side.  So how do you tell the difference? One of the keys is to look at the flower (a member of the Lily family so it has 3 petals, 3 sepals, 3 leaves - hence the name trillium) from the side.  T. sulcatum typically in Kentucky has the petals enclosing the ovary so that it is not very visible from the side and kind of looks like a candle snuffer.  T. erectum has, you guessed it, more erect petals from the side and the ovary is clearly visible.  One other closely aligned species is T. simile, but that does not occur in Kentucky, which helps identification.  Other factors to consider are smell, T. erectum smells like a wet dog, T. sulcatum has very little or a very faint odor. Supposedly T. erectum has a shorter pedicel and the the leaves are not as curled as they are in T. sulcatum, where they kind of look like canoes (use your imagination here).  Growing all the trilliums is pretty similar in the garden and thanks to nurseries getting divisions from existing stock and growing from seed (takes 5-7 years), many species are now available in the trade.  They like high organic or very rich soil that is well drained in a woodland setting and where the pH is normal to slightly acidic.  Because they like moist conditions, try not to plant them next to mature trees where there could be a moisture problem. Do not dig these from the wild because invariably they will die because they have a very delicate ecology and often you will notice smaller flowers for a year or two then the plants disappear because they are stressed.  Good companion plants include a variety of ferns, maybe some foamflower to fill in, ginger, bellwort, and Jacob's ladder.  The best time to plant them is right now - before the spring season arrives.