Sunday, May 13, 2012

Purple Thistle - Cirsium horridulum

Purple thistle (aka yellow thistle) (Cirsium horridulum) is an annual or biennial herbaceous "weed" that occurs throughout Florida and in much of the eastern seaboard - though it is classified as a state-endangered species in much of the northeast.  This is a plant of roadsides and other disturbed habitats, and thrives across a wide variety of soil types in full to partly sunny conditions.
As its Latin name implies, it is a robust, wickedly spined plant. The broad rosette of basal leaves may be several feet across.  The sharply toothed leaves are armed with stout spines at the end of each tooth.  This, and the milky sap it produces, protects it from herbivorous wildlife; but, like so many times in nature, the caterpillars of the little metalmark butterfly are uniquely adapted to feed on it.  This tiny, but beautiful butterfly, is featured at the top of this post, nectaring on an aster flower.
A husky flower stalk arises from the center of the rosette by summer.  It too is spiny and eventually reaches a height of about 3-4 feet. Large spiny flower heads form at the end of each stem - and along a few side stems near the top.  These open to large and very showy lavender flowers that are exceptional nectar sources for all types of pollinators.
Though few wildflowers are better nectar sources, purple thistle is impossible to control in a landscape setting. Once established, it often there to stay - producing new plants from underground suckers and from the copious fluffy seed that gets carried everywhere by the wind. I do not recommend it for landscapes, but it is a hub of activity if you are out looking for butterflies, bees, and the like.  When I am hiking or driving and see a stand of purple thistle, I always try to stop if I have my camera with me. You never know what you might see nectaring from it.

Mock Bishop's Weed - Ptilimnium capillaceum

Mock Bishop's Weed (Ptilimnium capillaceum) is a member of the carrot family.  It occurs statewide in Florida, in a wide variety of moist to wet soil habitats, but is also well adapted to average soils and can be found as a lawn or old-field weed.  Mock bishop's weed occurs in much of the Southeast and Midsouth to about Ohio.   Throughout this range, it is an annual that prospers by producing large numbers of seeds.
As a "wild carrot", this species produces a deep taproot, highly fragrant foliage, and umbels of tiny white flowers.  The taproot provides it with good drought tolerance once it is established and the foliage feeds the caterpillars of eastern black swallowtail butterflies.  In our landscape, mock bishop's weed shows up everywhere we water - especially around our potting benches, inside our flats of wildflowers, and in the wetland garden.  We weed some of it or we'd be overrun by this plant in just a few years, but we leave the rest for the butterflies. 
Mock bishop's weed rarely stands taller than 18 inches at maturity. Like many other "carrots" (e.g. dill, fennel), the main stem is hollow and a great many leaves attach to it and off the many side branches.  These leaves are compound with finely dissected leaflets.  The flower heads arise from the ends of every stem.
Many "carrots" produce flowers in specialized heads - called umbels.  Mock bishop's weed is no exception. Each bloom is tiny and bright white.  At full bloom, mock bishop's weed is attractive. This is a spring/very early summer bloomer.
This plant is rarely offered for sale by commercial sources; its main draw being butterfly gardeners interested in adding larval food plants.  Because it blooms early, it is one of the best larval food plants for eastern black swallowtails.  From my experience, it is their preferred spring plant and a great majority of 1st generation butterflies are produced from it.  If you add it, you are likely to have it forever if you plant it in a moist to wet location.  Just make sure you give it some bare soil for the seed to land on. 

Wednesday, May 9, 2012

Wild Sweet Basil - Ocimum campechianum

Wild sweet basil (Ocmium campechianum) is a state-endangered annual herb found only in the extreme southern tier of Florida counties - Collier, Monroe and Miami-Dade.  As its Latin name suggests, however, it is more common in Mexico - and it also occurs throughout much of tropical Latin America.  In those regions, it is used as a culinary herb or as a "cooling" tea.  It is also sometimes used to ward off mosquitoes - hence its other common name of "mosquito plant."  The genus, Ocimum, includes standard basil and all its many varieties.  Though our native basil seems to have rarely been used in that fashion, it has highly aromatic foliage.
Wild sweet basil is a tropical species that persists in frost-free areas by reseeding heavily.  It has no cold tolerance, but has fared well to date in our Pinellas County landscape despite some cold winter temperatures because seed has sprouted from frost-killed plants.  It is unlikely, however, to persist in areas where the climate is more harsh.
Wild sweet basil rarely stands much taller than 18 inches, but it rapidly becomes much wider than that.  And, because it reseeds so heavily, it often forms large patches of plants that can extend for many feet.  The leaves are oval, opposite each other on the stem, and about 2-3 inches long.  They are also slightly pubescent.  The stems are often purplish - especially on the newest growth. 
Flowering can occur throughout the year.  Like other basils, they occur in small terminal spikes. Each flower is pink/lavender in color and only about 1/8 inch across.  They are especially attractive to small bees.  As the flowers are pollinated, they form a small thin papery seed.
Wild sweet basil is an attractive and useful native wildflower that is easy to cultivate from either seed or cuttings.  It is, however, rarely offered by nurseries affiliated with FANN - the Florida Association of Native Nurseries.  With the strong attention that sustainable landscapes have garnered in recent years, it would seem that this is one native that might be offered more regularly in the future.  We often have a few plants for sale at Hawthorn Hill, but do not plan to add it as a regular feature of our nursery.  That could change if demand seemed to warrant it.

Monday, May 7, 2012

Small-fruited Bur-Marigold - Bidens mitis

Small-fruited bur-marigold (Bidens mitis) occurs nearly statewide in Florida, except for the extreme southern tier of counties.  Outside Florida, it is confined to the Atlantic Gulf Coast - the one-state-wide row of states from Texas to Maryland. Throughout this region, it is an herbaceous obligate wetland wildflower, common to a very wide variety of fresh and brackish habitats.  This species thrives in the open, but can tolerate partially shaded areas.
Small-fruited bur-marigold is similar to its close cousin, Bidens laevis.  Both are found statewide, but only B. mitis occurs in brackish systems as well as freshwater ones.  Though both species bloom mostly in the fall, B. mitis is more likely to also bloom in late spring and early summer.  Finally, there is an obvious difference in the foliage.  B. laevis has wide elliptical leaves that are unlobed while B. mitis has variable leaves, some of which have lobed margins.  I have written about B. laevis previously. The plants photographed above were in flower in late March.
Small-fruited bur-marigold is an annual.  Seedlings grow rapidly in the spring and can reach their mature height of 2-3 feet by March.  They are rather weak-stemmed plants and have a tendency to bend over under the weight of the open blooms.  They may occur on the shore of wetland systems, but more often occur in the shallow water edge, 4-6 inches deep.
The flowers are bright yellow. Both the ray and disk flowers are similarly colored.  Each is about 1 inch across.  Multiple flowers are produced on the long wiry stems and their many side branches.
Like all members of this genus, small-fruited bur-marigold produces seedheads full of small dark seeds (achenes) covered by tiny spikes that cause the seeds to stick to clothing and hair.  In this way, "beggar-ticks" as they are sometimes called, move about to new habitats and sometimes earn the ire of both hikers and pet owners.  B. mitis, unlike other species of this genus in Florida, do not have long "horns" at the end of their seeds that further enable them to stick, just many small spiny "hairs".
Small-fruited bur-marigold makes a beautiful addition to certain wetland restoration projects, but is not a great choice for home landscapes except in areas that will not be walked in and along shorelines of permanently wet systems. As such, it is sometimes offered by commercial nurseries that specialize in wetland restoration.

Sunday, May 6, 2012

Trailing Arbutus - Epigaea repens

Trailing arbutus (Epigaea repens) is another one of Florida's relict flora; a species exceedingly rare here, but more common to our north. This species occurs as an isolated population within Torreya State Park in Liberty County as well as in the three furthest western counties in the panhandle.  Because of its rarity and vulnerability, it is classified as a state endangered species.  It is far more common to our north and west, however; occurring in nearly every state in the eastern third of the U.S. and most of the southern tier of Canadian provinces to Manitoba. Throughout its range, it is most common to the understory of deciduous woodlands - in places where it is not routinely buried by leaf litter.
As its name implies, trailing arbutus is a low-growing ground cover. It spreads slowly by rhizomes and eventually occurs as a mat of deep-green evergreen foliage.  Each leaf is leathery and somewhat wooly, and the plants themselves rarely stand taller than about 4-6 inches.
Flowering occurs in very early spring, often before any of the other spring ephemerals have bloomed.  The bright white flowers occur in small clusters at ground level and are exceptionally fragrant.  The flowers soon give way to small fruits that are whitish and somewhat reminiscent of a raspberry.  The photos above were taken in Torreya State Park in early March.  Most of the flowers were well past blooming and the fruit were becoming well developed.
Trailing arbutus has potential as a ground cover for deciduous-shady woodland landscapes in north Florida, but it has never been propagated (to my knowledge) by anyone associated with the Florida Association of Native Nurseries - and, it is unlikely to be.  Though more common to our north, this species is unlikely to fare well here unless specimens close to our border are used.  I have read that it is difficult to propagate as well.
When all is said, this species is best considered to be another of Florida's interesting flora, appreciated in the woods where it occurs. 

Golden Ragwort - Packera aurea (fka Senecio aureus)

Golden ragwort (Packera aurea) is the only perennial member of this genus of wetland asters in Florida.  As such, it is also the only one to be grown commercially to any extent.  Golden ragwort is rare in Florida, found only in Liberty, Gadsden, and Leon Counties in the central Panhandle. It is much more widely spread outside our state, however, and occurs in nearly every state and province west of us to Manitoba south to Texas.
Golden ragwort is distinctive for its rounded basal leaves.  These remain evergreen through the winter months. The rich green basal leaves are, in fact, one of this plant's most attractive features.  In early spring, a flower stalk emerges from the center of the rosette and may reach 2-3 feet high. Like other members of this genus, multiple flower buds occur at the end of each stem and these open to clusters of canary yellow flowers.  In our garden here in Pinellas County, golden ragwort blooms in February to early March - making it one of our earliest wildflowers.  The flowers attract bees and butterflies. By April, the seedheads have dried and the flower stalks have withered.
Golden ragwort is a wetland plant and requires moist to wet soils to prosper. It will tolerate some drought during the cooler winter months, but do not allow it to get too dry during the heat of summer.  It also tolerates partial to mostly shady conditions, though it will bloom best if given higher levels of sunlight; just keep it wet if grown in the sun.
Though restricted naturally to a 3-county area in Florida, it can be grown well outside this in a landscape setting.  We have kept it for many years now in our wetland garden here at Hawthorn Hill and I suspect it could be grown even further south if given the conditions it prefers.  Golden ragwort is offered by a few nurseries associated with FANN - the Florida Association of Native Nurseries.  You may have to search a bit to find it, but it is worth the effort if you are looking for a wetland wildflower that is attractive for both its foliage and its flowers. 

Butterweed - Packera glabella

Butterweed (Packera glabella) (fka Senecio glabellus) is a common component of freshwater wetlands throughout Florida.  It also occurs throughout most of the eastern half of North America, from Ontario to the north and Texas to the south.  Within this range, it can be encountered nearly anywhere soils are moist to seasonally flooded.
Butterweed is an annual that often emerges in fall, overwinters as a basal rosette of leaves, and quickly sends up flower stalks in the spring.  Unlike the perennial species, Packera aurea, that is sometimes sold commercially in Florida, this species has alternate multi-lobed leaves that look a bit like those of many mustards (at least to me).  Butterweed, however, is a member of the Composite (Aster) family.
Tall, hollow flower stalks emerge from the center of each rosette in early spring. By its March/April flowering time, each may be about 3 feet tall.  Many buds form at the tip and these open to revel the canary yellow flowers.  Both the ray and the disk flowers are similarly colored.
Butterweed often forms dense stands in places where its growing needs are best met, and a stand of these in bloom can be spectacular.  The flowers are attractive also to a wide range of butterflies and bees so areas of butterweed are often a-buzz with activity. But, because the stalks are hollow, they often fall over if subjected to high winds or other similar forces.
Because its an annual, this butterweed has not generally been made available commercially as its perennial (and rarer) relative has.  It is easy to grow from seed, however, should you wish to add it to a wetland setting.  Collect the fuzzy seed as soon as it ripens in late spring/early summer and sow it immediately.  This species will persist and spread if it has open moist soils. It will prosper in full sun to partial shade if its soil-moisture needs are met. We do not propagate this at Hawthorn Hill at this time.

St. Peter's-wort - Hypericum mutilum

St. Peter's-wort (Hypericum mutilum) may be the most overlooked member of this large genus in Florida. Though the plants themselves are large enough, the tiny yellow flowers are noticeable only on close inspection.  And, when that happens, it is easy to see that this species is, in fact, a St. John's-wort member.
St. Peter's-wort occurs throughout Florida and in nearly every state and province of North America. Throughout this range, it is most frequently encountered in moist, open habitats - the upper edges of marshes and low pockets in pine flatwoods, especially.  St. Peter's-wort is an annual (sometimes a very short-lived perennial), but in Florida it reaches blooming size by late April to early May.  Mature plants are seldom taller than 2 feet and they tend to be rounded in shape - sometimes taller than wide.  The oval leaves are opposite each other on the stem and they clasp the stem. The bark on the lower, more-developed stems is cinnamon colored and peeling.
Like other members of this genus in Florida, the flowers are yellow - a pale lemon yellow instead of a deep canary color.  Each bloom is no more than 1/3 inch across and has 5 petals arranged  in a starlike pattern - not whorled like a pinwheel.  These attract very small pollinators.
St. Peter's-wort is not likely ever to be the subject of landscape interest because of its annual nature and its tiny flowers, but it is an interesting species nevertheless.  Look for it as you hike outdoors anywhere in Florida at the edges between upland and wetland.  If you haven't noticed it before, I bet you will find it if you look for it.

Saturday, May 5, 2012

Grassleaf Yellow Star Grass - Hypoxis juncea

Grassleaf yellow stargrass (Hypoxis juncea) is a diminutive member of the Hypoxidaceae family, though it has at times been included as an iris and as a lily. Regardless, it is a monocot - like the lilies, irises, and amaryllises and arises each spring from a tiny bulb. Grassleaf yellow stargrass is common to most of Florida, in moist woodlands. Its national range is restricted to the Deep South - from Alabama to North Carolina. In Florida, it is most common in wet to seasonably moist pinelands.

Yellow stargrass is a perennial that dies back to the ground during a brief period in winter. In warm years, however, it is possible to find it in bloom at any time. Slender grass-like leaves extend about 6-12 inches from the bulb, but often lie near the ground instead of standing upright.

A single yellow flower is produced at any one time, though individual plants may produce more than one flower during the year. These are bright canary-yellow in color, about 1 inch across and consist of six petals in a star-shaped arrangement. Flowering in the southern half of Florida can occur during any month, but is often confined to spring through fall elsewhere. The flowers are showy, but are held close to the ground.

Yellow stargrass is not available commercially to the best of my knowledge and we do not propagate it at Hawthorn Hill. If you had access to a source, it should be used in an open sunny, moist setting that does not stay dry for long - especially during the hot summer months. Use it in the front of a garden and make sure it does not get crowded out by taller more-aggressive species.
Look for yellow stargrass any time you are hiking in flat open areas in Florida. You may have to look close for it, but once your eye is trained to see it, I expect you will see it often.

American Squawroot - Conopholis americana

American squawroot (Conopholis americana) is the only member of this genus in Florida and part of a family (Orobanchaceae) that acts as root parasites.  American squawroot is also in the smaller group in this family that does not produce chlorophyll - making it completely dependent on its host for its nourishment.  This is a widely occurring species in Florida, and can be found throughout most of the northern half of the state.  It is also widely distributed outside of Florida.  American squawroot is found from Manitoba in central Canada to our north and south to Mississippi.  Throughout this range, it is most often found in the understories of well-drained woodlands.
American squawroot is deciduous and emerges in the spring.  It does not have leaves and produces a cluster of pine-cone-shaped flower heads in early spring to early summer. The plants photographed above were just past their peak of flowering in early March.  The individual flowers are yellowish white. They are subtended by an orange-tan bract. I have not observed the types of pollinators that visit this plant, but suspect it is of most interest to bees and pollinating flies.
American squawroot is never likely to be the target of home landscaping interest, but it will always remain an interesting component of our flora. Look for it in the understory of well-drained oak woodlands and admire it for its unique character.

Wild Comfrey - Cynoglossum virginianum

Wild Comfrey (Cynoglossum virginianum) is rare in Florida, found only in Gadsden and Liberty Counties in and around Torreya State Park.  As such, it has also been classified as a state endangered species. Like so many of our natives, confined around Torreya, it is much more widely distributed elsewhere outside of Florida. Wild comfrey is distributed north to Quebec and the Yukon in Canada, and westward in the U.S. to the Dakotas and Texas.  In Florida, wild comfrey occurs in the understory of deciduous hardwood forests. Here it blooms before the canopy closes and it gets protection from the summer sun after flowering has past.
Wild comfrey is a perennial herb in the Borage family.  It dies to the ground each winter and emerges in the spring.  For the most part, it exists as a basal rosette of broadly oval, fuzzy leaves.  Each is nearly 8 inches long and about 4-5 inches wide.  A flower stalk is produced from the center of this leaf cluster in spring and it eventually stands 2-3 feet tall.
Flowering occurs in March to very early April in Florida.  Each flower stalk has several side branches and each has a small cluster of small flowers.  Most often, these flowers are pale blue in color, but some are nearly white and a few are almost pinkish. 
Wild comfrey has never been offered for sale by any of the nurseries associated with FANN- the Florida Association of Native Nurseries and it is unlikely to be offered in the future.  As a relict species, wild comfrey is not widely adaptable to most Florida landscape settings. I have not tried to propagate this species though I suspect it could be found from commercial sources outside Florida.  In my opinion, this species is just another good example of an interesting part of our flora that should be looked for in the right places and admired there.

Friday, May 4, 2012

The New Book is Here!

Just received my copies from University of Florida Press!  Cover by my friend, Christina Evans.  If you purchase a copy, I sincerely hope it is helpful in your gardening efforts.  Please let me know.  I enjoyed the writing and photographing part, but the real test is whether it actually helps you all.