Pale Meadowbeauty - Rhexia mariana

Pale meadowbeauty (Rhexia mariana) occurs nearly statewide in Florida in open savannas and marsh edges.  It also is common throughout much of the eastern half of the U.S.  Within this region, flower color can be variable, from the nearly white form pictured above to pink (a color common to many other meadowbeauties). The flower-color variability could make identification confusing, but this species has very conspicuous "hairs" along the stems. It is very similar to R. nashii, but the hypanthium (the tube portion of the urn-shaped seed capsule) is much longer in the latter.
This is a perennial herbaceous wildflower that often dies back to the ground each winter and reemerges in the early spring. Mature plants reach a height of 2-3 feet by summer. The leaves are linear and opposite each other on the very hairy stems.  Like other members of the genus, pale meadowbeauty forms extensive colonies by underground stems.
Flowering occurs in early summer to fall.  The four broad petals recurve slightly backwards and the overall flowers are about 1 inch across.  The stamens end in conspicuous yellow curved anthers and, following pollination, the urn-shaped seed capsules are distinctive.
Meadowbeauties, as a genus, are only rarely propagated and sold commercially.  All make wonderful additions to a moist-soil setting, if provided sun to mostly sunny conditions.

Zigzag Spiderwort - Tradescantia subaspera

Common spiderwort (Tradescantia ohiensis) is so common in Florida that we sometimes forget our state hosts other species.  Zigzag spiderwort (T. subaspera) is one of those. Zigzag spiderwort is found in Florida only in the central Panhandle, in a four-county area around Torreya State Park and Apalachicola National Forest.  It also occurs to our north, across much of the Midwest to the Northeast. In nature, this spiderwort occurs in partial to nearly full shade beneath the understory of upland deciduous woodlands.
Zigzag spiderwort is a perennial herbaceous species that dies back to the ground each winter and reemerges in spring.  Mature plants are a bit lanky and stand 12-18 inches tall by early summer.  Although it looks a lot like common spiderwort, one distinct difference is in the foliage. Zigzag spiderwort's leaves are much broader at the point of attachment to the stem than they are elsewhere. In common spiderwort, the leaves are pretty much uniformly the same width throughout.
The flowers of zigzag spiderwort are similarly shaped to common spiderwort, but tend to be much smaller in size.  In all of the plants I have seen, they are light blue in color and there does not seem to be the variability in shades of blue present in common spiderwort.
Although zigzag spiderwort is tough and adaptable to a wide variety of growing conditions (provided it is not planted in full sun), it is not currently propagated by anyone associated with the Florida Association of Native Nurseries (FANN) and it seems unlikely to be anytime soon. This would be an interesting addition to a shade garden as so few wildflowers bloom in summer in shady settings.

Chapman's Crownbeard - Verbesina chapmanii

Chapman's crownbeard (Verbesina chapmanii) is another interesting Florida plant, endemic to a 6-county area in the central Panhandle.  Its core population is found within the Apalachicola National Forest, where these photographs were recently taken.
Chapman's crownbeard is a perennial forb with rough-as-sandpaper oblong leaves that vary in length from 1-4 inches.  The leaves alternate on the wingless 2-3 foot tall stems. Rounded flower heads form atop these stems in late spring and early summer. Each head is about 3/4 inches across. The bright yellow flowers are quite distinctive; no ray flowers are produced and they appear similar to those produced by Palafoxia spp.- except for the canary yellow color. Like other members of the aster family, the blooms attract pollinators.
Chapman's crownbeard occurs in open wet prairies, pine flatwoods, and bogs and forms an interesting part of the extremely diverse wet-prairie habitats found throughout the Apalachicola National Forest and parts adjacent to it.  Though several members of this genus have become common cultivated wildflowers in Florida, Chapman's crownbeard has never been offered for home gardens to my knowledge. I suspect it is somewhat adaptable, but have never grown it myself to verify that.  Watch for it along roadsides in moist open areas of the Forest and admire it for its simple beauty.

White Birds-In-A-Nest - Macbridea alba

White birds-in-a-nest (Macbridea alba) is endemic to the Apalachicola National Forest region of Florida - Liberty, Franklin, Gulf, and Washington Counties. In this localized area, it can be relatively common in scattered populations, but is listed as a state endangered species and by the federal government as a threatened species because there are so few of them.  This is a plant that occurs in seasonally wet, open habitats - wet prairies, flatwoods, and bogs.  The plants photographed above were found in an expansive bog dominated by yellow pitcher plants (Sarracenia flava), bit in elevations slightly higher than where the pitcher plants were thriving.
White birds-in-a-nest is a member of the mint family.  Few native mints are truly pure white, and this species stands out among the understory because of the way it glistens in the sun.  Its common name is easily understood by looking at the third photo above.  Flowers open atop the 18-inch stem in June and July. As they open, the winged blooms encircle the unopened white egg-shaped flower buds.
This is a perennial. I do not know if it persists overwinter as basal leaves or if it dies back to the ground; none of the published resources I have consulted describe this feature. Regardless, it is not a very interesting foliage plant. White-birds-in-a-nest reaches a mature height of 12-18 inches and rather succulent elliptical leaves line the stems, opposite each other, and with rough teeth at the outer margin.  The plants can be solitary or in small clusters.
White-birds-in-a-nest is threatened by modern forestry practices and by changing hydrology. It is not a good candidate for home horticulture because of its habitat specificity, but it is relatively well protected at this time in the State Forest where its well being is closely monitored.

Nuttall's Thistle - Cirsium nuttallii

Although there are nearly a half-dozen thistles sporadically present in a few north Florida counties, only two are found within the peninsula.  I have previously written about purple thistle (C. horridulum) which is common in open disturbed sites statewide. Nuttall's thistle (Cirsium nuttallii) is the second species, found throughout Florida, except much of the western panhandle, in sunny, open disturbed habitats.  Nuttall's thistle also occurs in much of the Southeastern Coastal Plain. It is not uncommon to see this and purple thistle growing in the same location, but they are distinctly different from each other.
Thistles are biennials; they do not flower in their first year, but develop a deep taproot and a basal rosette of leaves. Flowering occurs in the second year, they go to seed, and then the plants die. The large number of seeds produced by their parents, however, ensures that more plants will emerge next spring.
Nuttall's thistle is a robust, lanky species that reaches a mature height of 5 feet or more. The basal leaves are more narrow than in purple thistle, but they are equally armed with numerous sharp spines.  In fact, the entire plant is exceedingly spiny.
A great many flower heads are produced atop the stems in summer.  These too are much narrower than in purple thistle. The flowers vary in color from nearly white to a more common light pink.  Plants remain in flower for many weeks, and as with other thistles, they are exceedingly attractive to pollinating insects.
Though thistles are wonderful plants for pollinators, they are extremely difficult to control in a landscape garden.  Their thorniness makes working with them a challenge and the fact that they need to reseed to persist means that they need to be left alone until the seeds are dispersed. By then, you may have hundreds of seedlings germinating in every corner of your landscape (and in those of your neighbors).  In many Midwestern states that I have lived in, growing thistles in a landscape is prohibited because they can be invasive.
If you have a more naturalistic setting and wish to add this species, despite its drawbacks, it is easy to propagate from seed collected when mature ("fuzzy"). This species is not currently available from commercial sources. Use it in out-of-the-way locations, away from pathways and trails and be prepared to weed out seedlings that appear in locations where they are not desired. Weed them when very small, when they are less well armed by thorns. Nuttall's thistle does well in partly sunny areas, but also can be grown in full sun.

Baldwin's Eryngo - Eryngium baldwinii

Baldwin's eryngo (aka Baldwin's button snakeroot) (Eryngium baldwinii) is a diminutive prostrate perennial common to moist open to partly sunny habitats throughout most of Florida and parts of southern Georgia.  A member of the carrot family, this deciduous wildflower forms a taproot and tends to hold its basal leaves through winter. Growth is quick in the early spring and it then proceeds to creep across the ground, often less than an inch tall.  The thin stems branch outward in many directions, extending up to 2 feet from the root. The small, finely dissected leaves are sharply pointed and slightly prickly.  The small button-shaped flower heads emerge from the axils of each leaf.
Baldwin's eryngo is easily overlooked when not in bloom as it blends in with the other plants of the understory, but it stands out once the bright blue flowers are present.  Flowering can occur in most months, but is most common in early summer. The plants above were photographed in mid-June at the outer edge of an oak hammock, in disturbed soil, next to an infrequently used unimproved roadway. The flower heads are composed of many dozens of extremely tiny flowers. Each head is no more than 1/8 inch across. The flowers are pollinated by equally small bees and butterflies; one pollinating bee is apparent in the middle photo.
Several eryngos serve as larval plants to the eastern black swallowtail, but this species has not been documented as one of them. Baldwin's eryngo could make an interesting ground cover in moist partly sunny locations, along trails and walkways, but it has never been cultivated commercially to the best of my knowledge.  It exhibits some drought tolerance, once established, but will flower best if given some sun. Plants grown in full sun, require more moisture.