Can you name a small evergreen native-to-Florida tree that has good salt and alkalinity tolerance, pretty white flowers, edible reddish orange fruit, interesting exfoliating reddish-brown bark and a reputation for curing diarrhea? Well, it’s Myrcianthes fragrans, Simpson’s stopper or Twinberry.
It’s modestly threatened in the wild. While rarely encountered, it can be found here and there in the landscape trade in Florida. We’ve had this plant for a good number of years at SFA Gardens and it’s performed well, but we like it even better in our Moody Gardens research plots on Galveston Island where it’s held up to epic wind and salt challenges. Of course, there are some negatives. First is cold hardiness. While it’s considered a Zone 8B or 9A plant, we beg to differ. It’s been quite tolerant of freezing temperatures into the teens at SFA Gardens and returned well from near the ground after the February 2021 winter storm Uri event when temperatures fell to -4oF, a record all time low in our Pineywoods Texas home. A second characteristic we’ve observed is that it’s a bit slow to make a strong salable plant. From seed or cuttings, Simpson’s Stopper takes its time.
In the wild in Florida, it occurs naturally in coastal strands and hammocks. There it is reported to have year-round blooms that attract a variety of butterflies and bees. The fruit is appreciated by many bird species and while the sweet flesh is edible to humans, eating the bitter seeds is not recommended. The flowers remind me a bit of widow’s frill, Silene stellata, and are dramatic in full bloom. Each fragrant flower has four white petals and many long white stamens. Leaves are bright green, ovate to elliptic and leathery. When crushed, they emit a citrusy aroma. Fruits start off as greenish ovoid berries that transition into bright reddish-orange as they mature. They are typically born in pairs (hence the name “twinberry”). There are a number of varieties in the trade but they are difficult to find. In general, seedling grown plants in Florida top out at around 20’.
Plants grown in sun are denser and flower more. The champion Simpson’s stopper comes in at 38 feet tall and it’s living in Okeechobee County in Florida. We have a form from Mexico via Adam Black and it appears to differ little from the Florida genotypes. We have a variegated form, ‘Stoppermorph’ but it doesn’t bloom at all and, for us, it seems close to impossible to root. That said, we have found that it is sold by Agristarts as a tissue culture plant.
There’s a dwarf version form called ‘compacta’ on our wish list. Finally, Jim Berry of JBerry Nursery picked out several seedlings from our nursery and has one that sports showy burgundy new growth. Hopefully, we can twist Jim’s arm and he’ll let us have it back once he’s gotten it multiplied.
With so many positives, we think this plant is a Gulf South native that deserves more attention. There’s good opportunity for selecting improved forms and we think this might be a perfect patio container plant that needs protection only from the worst freeze events.