Frostweed in the Dr. John Gorrie Ice Garden

When it comes to our Historic Tree Grove, we always feel a bit sorry for the Dr. John Gorrie Red Cedar. It's tucked away in a corner of the garden where it's often overlooked. The tree itself had some difficulty getting established, so although it's the same age as our Fort Matanzas Red Cedar, it's significantly smaller. The garden area around it is small, too, and a bit overshadowed by some of the bigger gardens nearby. And how many people have actually even heard of Dr. John Gorrie anyway? (You can learn more about him - and why his tree has an Ice Garden planted around it - by clicking here.)

But right now, in mid-fall, the Dr. John Gorrie Ice Garden is putting on quite a show. The Frostweed has grown to 8 feet tall and is covered in small white blooms that are a draw for every pollinator in the area. They flank the tree on either side and tower above the Dr. John Gorrie mural bench (shown above), drawing the eye to this somewhat neglected corner of the Tree Grove.

Frostweed (Verbesina virginica) is a native wildflower in the aster family, found in much of the eastern US. It prefers part sun and moist soil, but thrives in a variety of conditions. Our Frostweed receives pretty much full sun, and grows in average to dry soil. This plant dies to the ground (or near the ground) each winter, returning to grow rapidly over the spring and summer months until it tops out with heads of small white flowers beloved by butterflies and bees. The foliage a host plant for the Summer Azure, Bordered Patch, and Silvery Checkerspot butterflies within their respective ranges.

"Frost Flowers" on Verbesina virginica,
photographed by  Bob Harms in Texas

Like many native wildflowers, Frostweed has a variety of other common names. One of these is "Winged Stem", referring to the wing-like appendages that grow along the tough, thick stem of the plant. Others, like White Crownbeard, are easy to understand given the white-flowering nature of the plant.

But the common name "Frostweed" doesn't refer to the plant's tendency to bloom late in the season close to frost-time. Rather, it refers to the ability of the plant to exhibit crystallofolia, crystallized ice formations that are formed when water is emitted from the stem near the base of a dormant plant during a hard freeze. Relatively few plants exhibit this behavior, so the tendency toward this interesting natural phenomenon has given this plant one of its common names. This is a curiosity we're unlikely to experience first-hand in Tampa, but one that is undoubtedly fascinating to observe.

Frostweed is available at many native plant nurseries, especially in late summer and early fall when it begins blooming. It's not the tidiest of plants, and belongs at the back of a wildflower or native butterfly garden where it can soar to the skies each summer, then die back for a well-deserved rest in the winter.