A Xeric Garden

A dwarf agave with rosettes less than 12 inches wide toughs it out in pure Florida sand. My guess is that it is one of the many forms of Agave potatorum. The genus Agave is native to the New World from the southern United States to South America but it reaches its greatest diversity in Mexico.

I have been watching the endeavors of a local gardener with keen interest. Apparently having grown weary of tending a lawn, this gardener removed all grass from a small front yard and is growing tough desert plants. Although markedly different from the typical pseudo-tropical south Florida garden, it shares with such gardens the presence of plants from far-flung regions of the world and a lack of any native plants.

Euphorbia tirucalli is native to Madagascar and is characterized by a highly toxic and caustic sap. It has also been linked with Burkitt's lymphoma, a typically rare cancer that tends to be associated with regions where Euphorbia tirucalli is extensively used as a hedge plant. The pictured plant is a cultivar with brightly colored new growth called 'Sticks on Fire.'

An Opuntia species with a growth habit similar to the native semaphore cactus (Opuntia corallicola); however, the native semaphore cactus is markedly spiny and tends to have pads of a lighter green color.

The so-called Madagascar palm is not a palm at all. It is Pachypodium lamerei, a spiny-stemmed succulent from Madagascar in the oleander family (Apocynaceae). It should be handled with care since the spines are extremely sharp and can cause severe injuries or infections if they happen to impale the knuckles or joints of the fingers.

This aloe is very similar to Aloe arborescens from Africa; however, the rosettes are much smaller than that species. I am guessing that perhaps it is a small-growing hybrid of Aloe arborescens.

Images and text © 2012 Rufino Osorio

Asclepias curtissii

Curtiss's milkweed is a state-listed endangered species with specialized habitat requirements. It is found almost exclusively in scrub habitats where it tends to favor areas of pure sand with very little vegetation. It is remarkable in that it is one of the few plants that readily colonizes areas of pure sand at the edges of stable blowouts.

Geologically, a blowout is a depression in a sandy habitat caused by strong winds. Blowouts get their start when some disturbance, such as fire, extended drought, off-road vehicles, or human or animal foot traffic, results in the loss of protective vegetation. Sometimes, a positive feedback cycle forms where the blowout causes plants to die along its periphery, this makes the blowout bigger, and this in turn causes more plants to die, resulting in an ever expanding area of pure sand devoid of any vegetation.

Curtiss's milkweed occurs as a native plant only in the State of Florida. Within the state, it has a wide range and has been recorded in many counties from Clay County in the north to Broward and Collier counties in the south; however, it is endangered in spite of its wide distribution because of its exacting habitat requirements and habitat loss.

 

© 2010 Rufino Osorio.

Funastrum clausum

Funastrum clausum is a vigorous vine with long stems capable of climbing to great lengths. It is commonly known as white twine-vine or white milkweed-vine and is usually associated with wet areas such as ditches, pond margins, and the edges of mangroves and swamps. The plant is tolerant of disturbance and is occasionally found in overgrown thickets in old empty lots and along railroad tracks. It has a variety of horticultural uses and can be grown in a moist, sunny area wherever a vigorous, freely flowering vine is desired. It is also highly recommended for insect and butterfly gardens since the sweetly fragrant flowers attract a wide variety of insects and the foliage is eaten by the caterpillars of monarch, queen, and soldier butterflies.

Funastrum clausum is native to Florida and Texas in the United States. Outside of the United States, it occurs throughout a very wide area from Mexico to Argentina, as well as in the Caribbean.

Until recently, this plant was known as Sarcostemma clausum and it is still found under that name in many publications and web sites.

© 2010 Rufino Osorio.