Sunday, May 8, 2011

Sandweed - Hypericum fasciculatum

Sandweed (Hypericum fasciculatum) is yet another evergreen wetland St. John's-wort found statewide and limited to the states of the Deep South.  I have compared it previously with coastalplain St. John's-wort (H. brachyphyllum) as the two share some of the same characteristics; namely flowers with 5 petals and needle-like leaves.  Compare the foliage of the two and it is not difficult to see the differences. While coastalplain St. John's-wort has leaves that fold backward, sandweed has flat leaves with no apparent fold. 
The other obvious difference lies with its growth form.  Sandweed reaches a mature height of about 5 feet. The bark is reddish and often peels back; somewhat like that of the gumbo limbo tree.  In sites that remain flooded for long periods, sandweed also forms adventitious roots; somewhat like the prop roots of a red mangrove, but thin and wiry. Mature sandweed forms an attractive, but somewhat irregular shrub.
Flowering can occur from late spring through fall.  Each flower is no larger than 1/3 inch across, but large numbers can be present at any one time.
Sandweed is sometimes available commercially, but is grown mostly for wetland restoration projects.  It is particular to hydrology and requires seasonably wet soils, but water depths no greater than about 6 inches.  I have grown this species successfully in my wetland garden at Hawthorn Hill, but have not found it to be especially long-lived.  It also has not spread by seed like many of my other St. John's-worts; seemingly because something was "missing" in its planting location.
If you have the right conditions, sandweed makes an extremely attractive addition to a pond edge. Use it in the middle of the planting in areas that occassionally flood to depths of 6 inches or less.

Coastalplain St John's-wort - Hypericum brachyphyllum

Coastalplain St. John's-wort (Hypericum brachyphyllum) occurs statewide on stream banks, pond margins, and wet savannas and pine flatwoods.  It is a Southeastern species that occurs only in the Deep South. It is an erect perennial evergreen shrub that reaches a mature height of about 4 feet.  Florida is home to 31 separate species of St. John's-worts and they can be difficult sometimes for the average person to differentiate.  The first key should always be habitat.  Many, like coastalplain St. John's-wort, are wetland species that rarely stray too far from wet or saturated soil.  The second is leaf shape. Coastalplain St. John's-wort has thin, needle-like leaves that are strongly revolute - the leaf margins are rolled backwards. The third is the number of petals. Most, like this species, have 5.  The fourth is the overall aspect of the plant.  Coastalplain St. John's-wort forms a round, dense bush that is somewhat uniform.
This is a common species to wet habitats.  In these habitats, it may be most confused with sandweed (H. fasciculatum); the latter being differentiated by its somewhat taller and irregular stature and its needle-like leaves that do not roll backwards along the margin. Sandweed also often develops reddish peeling bark - and prop roots when it grows in flooded situations.
Coastalplain St. John's-wort is an attractive member of this widespread genus, but has never been propagated as far I as I am aware by anyone associated with FANN - the Florida Association of Native Nurseries.  Its rounded evergreen aspect and bright yellow flowers have great aesthetic appeal, but it requires moist to wet soil to prosper.  Use it along the edges of wet to permanently flooded habitats, but near edges where its smaller size will not get lost.
We do not propagate this species at Hawthorn Hill.

Saturday, May 7, 2011

Dwarf Dandelion - Krigia virginica

Dwarf dandelion (Krigia virginica) is a tiny member of the aster family, but only distantly related to the true dandelion (Taraxacum officinale); a non-native species from Eurasia more common to states to our north.  Dwarf dandelion is found in a variety of upland habitats throughout the northern half of Florida. It is also found in most states and provinces in the eastern half of North America.
This is an annual that forms a basal rosette of strap-like leaves, with irregular teeth - each about 2 inches long.  They look very much like a dwarf version of the common dandelion. Multiple flower stems arise from the central portion of this leaf mass and reach a height of about 2-3 inches. The small yellow flowers occur one per stem in the spring and are about 1/2 inch across. The flowers remain open for at least a week and eventually produce a fluffy seed head - again, much like the common dandelion.
It is unlikely anyone will ever offer this diminutive wildflower for sale.  It is an attractive plant nevertheless.  Look for it in open sunny well-drained habitats in April-May and admire its simplicity.

Late Purple Aster - Symphyotrichum patens

I love asters for a number of reasons.  They have great value in the butterfly garden and most have wonderful blossoms that open primarily in the fall.  Regrettably, few of Florida's many native asters are grown and sold commercially at this time.  It has been one of my primary missions at Hawthorn Hill to rectify this and bring the best into cultivation - including the beautiful late purple aster (Symphyotrichum patens).
Late purple aster has been reported in scattered populations within 6 counties in north Florida. from the far western panhandle to Dixie and Duval County.  It is more common to our north, however, and is found in nearly every state in the eastern half of the U.S. from Maine to Texas.  
This is a drought tolerant perennial aster and occurs in a variety of upland habitats; but not the most excessively well-drained sandhills and scrubs.   Plants die back to the ground in winter and emerge in early spring.  Growth is rather rapid and plants reach their mature height of 2-3 feet by mid-summer.  Multiple stems are common and each plant may be nearly as wide as tall. 
Foliage is a rich green and the leaves are about 1 inch long and elliptical, sometimes with a wider base where they attach to the stem.  The leaves get noticeably smaller up the stem and closer to the flowers.
Late purple aster produces extremely showy flowers in late summer to fall.  The ray petals are a rich lavender color and they surround a bright yellow central disk.  A mature plant in full bloom may have dozens of flowers open at one time and they beckon a wide variety of pollinating insects, including butterflies and bees.
Like most native asters, late purple aster suckers - but not aggressively.  Over time, multiple stems emerge adjacent to the main stem and plants become quite "bushy." For this reason, they should be initially spaced no closer than 2-3 feet apart in the garden.  Use this wonderful aster in a mixed wildflower planting in average growing conditions and plant them in the middle of the garden.  It mixes well with other asters, grassleaf goldenaster, downy phlox, black-eyed susan and other medium-sized species.
I am not aware of any nursery associated with FANN (the Florida Association of Native Nurseries) that has ever offered this stunning aster for sale.  We are hoping to have seedlings available at Hawthorn Hill in spring 2012.  If you are interested, let me know.

Tuesday, May 3, 2011

Indian Plantain - Arnoglossum floridanum

Indian plantain (Arnoglossum floridanum) is endemic to Florida and found in sandy upland habitats in the peninsula from our northern border south to Sarasota and St Lucie Counties.  While most members of this genus are wetland plants, Indian plantain requires deep sands and ample sunlight to prosper.
Indian plantain is not our showiest wildflower, but I love its foliage and overall aspect.  In most winters, it loses its broad, almost succulent basal leaves and retires below ground.  They emerge early and quickly form a basal rosette that is quite attractive.  Each leaf is nearly round and thick, with teeth along the outer edges. 
A central flower stalk is produced in late spring and reaches a mature height of 2-3 feet by late April.  A broad flat umbel of flower buds are produced at this time; each bud oval in shape and noticeably keeled (winged).  The first time I saw this plant in the wild, I thought these buds were the unripened seed capsules as they do not look like typical flower buds in the aster family.  By early May, these buds open and the rayless tubular flowers emerge.  Each is greenish white with a bit of maroon coloring in the reproductive parts.  Strange, but not showy, they attract pollinators just the same.
Indian plantain has never been offered for sale commercially by any of the nurseries associated by FANN (fka AFNN), the Florida Association of Native Nurseries, and is unlikely to be added anytime soon.  I love this wildflower just the same and have grown it in my Pinellas County landscape for several years.  It makes an interesting addition to a mixed wildflower planting in well drained upland soils.  Use it near the back half of the planting bed and combine it with other medium to tall sandhill species such as blazing star, Silphium spp., Carphephorus spp., and various asters.  It is exceptionally drought tolerant and easy to maintain.
Each year, I grow a few extra of this one at Hawthorn Hill.  If you are interested, let me know and I'll start a few more.