Sunday, December 26, 2021

Sea Lavender

The first time I saw sea lavender, Argusia gnaphalodes, was somewhere in the Caribbean, possibly Grand Cayman, or Aruba, over 30 years ago. The beauty of its green-gray whorls of silky soft leaves so impressed me that I pinched off a tiny piece and showed it to the agricultural customs agent at Miami International Airport. He identified it for me, and explained that it once had been common along Florida east coast beaches, but was becoming increasingly rare due to development. (Environmental laws give Florida's wetland plants some protection. But some of the most rare and vulnerable native species require high and dry land, precisely the sites most coveted by developers, and often come out the losers).

Argusia gnaphalodes - Tip of Stem


After moving back to Florida in 1990, I began looking for the plant - in vain. So far my sources disagree on whether the plant occcurs naturally on the state's sw coast. Next year I will be stalking local state park and public beaches in search of it. Otherwise, it is native to Florida's east coast north to Brevard County, the Keys, West Indies, Yucatan Peninsula, and the Caribbean coast of central America and Venezuela. 

 Finally, about 2 years ago, I discovered a row of scraggly and generally unimpressive pots of Argusia at the All Native Plant Nursery in Fort Myers*, and pounced. Over the last 2 years it has become a handsome, fully-leafed out shrub about 3-and-a-half feet tall and wide. Barring calamity, it will keep spreading, though perhaps at a slower pace.



Argusia gnaphalodes  - Front View


I planted it in March, several months before the advent of the rainy season. I watered it well for the first week or so, until it seemed to be doing fine on its own, and since then I have neglected it completely, even though it is growing in one of the most difficult areas of our yard - a south-westerly slope of pure sand and brutal daylong sunshine. The summer rains no doubt were crucial to its establishment. 

In fact, gardeners living farther inland, where drainage is not so severe, and salt-laden wind not so common, might have trouble cultivating sea lavender, because it cannot take saturated or highly organic soils. It might also be subject to mildews and molds further inland, where there is less wind - speculation on my part, but possible.

(I have found transplanting native plants during the fall risky. I don't think the plants are programmed to grow in the absence of sustained rain, and stay in a semi-dormant state either until they die or the summer returns. No amount of watering seems to compensate for regular, saturating showers).

Like many plants in the Borage Family, Argusia gnaphalodes is extremely hairy everywhere except the petals and fruits. A dense covering of flattened hairs protects the succulent leaves from dehydration, too much sun and salt. It also gives them the silky softness of a puppy's ear. The leaves reflect silver in bright light, so much so that it's easy to overexpose photographs. In lower light, the plant can appear quite blue. 



Older Flowers - Low Light

Arg-The Latin root of the genus name, Argusia, refers to bright or silver light. The species name derives from a superficial resemblance to a genus of weedy winter annuals in the Aster Family, Gnaphalium.  

The leaves, flat, slightly succulent, and a little spatula-shaped, alternate around the stem, and terminate in a dense whorl. They are about 3-4 inches long and one-quarter inch wide. As the stem elongates, lower leaves die, but don't fall off immediately. Eventually the bottom third of the plant will show these bare stems. The habit may not be to everybody's taste, but I think it makes the plant more interesting. Pendant stems can root, which makes Argusia an important dune-stabilizing plant. 



Backside of Plant - One Stem Starting to Droop

The flowers are formed in a tightly wound cyme, which straightens as the blooms mature. 5 petals, somewhat crinkled, are united at the base. Young flowers are white, with the centers turning pink-maroon as they age. They are said to be mildly fragrant, but so far I haven't been able to catch that. 



Young Flowers


Fruits start out yellow-green, and turn brown or black as they ripen. I haven't seen any ripe fruits yet, so I suspect something eats them before I notice,




Immature Fruits


One of the main reasons this gorgeous plant isn't grown more is that basically nobody knows about it, which is a shame, because for coastal landscapes, it's unbeatable. 



See my blog post, All Native Plant Nursery, April 9, 2020.