Sunday, February 24, 2008

Sea Lavender

What’s still green: Conifers, rose stems, yuccas, rockrose, coral bell, sea pink, sea lavender, snapdragon, Saint John’s wort, yellow evening primrose, Mount Atlas daisy, chrysanthemum, some grasses

What’s gray or gray-green: Salt bush, winterfat, snow-in-summer, some pinks.

What’s red: Cholla, some pinks, small-leaved soapwort, coral and purple beardtongues, purple aster.

What’s blooming inside: Aptenia, zonal geranium, kalanchoë, Christmas cactus.

Animal sightings: Quail near cholla, smaller birds in peach and cherries; both were in scavenging bands rather than larger tribal groupings.

Weather: Snow midweek, rain Friday night, freeze and thaw continued on still frozen ground. 11:18 hours of daylight, if we’re lucky.

Weekly update: The freeze and thaw continues to take its toll. My sea lavenders kept their leaves until the heavy snows in December, when all but a few turned brown. When the snows disappeared and the cold remained the first of January, more died. This past week, all but a few hidden under other plants turned leathery with dessication. This is the third time since I planted these perennials in 2000 that some leaves have remained this long.

Chance has always played an important role in their lives. When I designed my garden, I simply said, I don’t have the instincts needed to plan an herbaceous border, so everything pink will go on the east side of the house, the blues on the west, and the gaudy reds, yellows and oranges in the center.

The size and shape of the beds followed the way a backhoe driver had carved, then leveled land from a hillside. On the east, there was only a foot between a retaining wall and the four feet clearance I wanted for the house. On the west a little more that two feet existed before the ground began sloping away.

Once I made my plans, such as they were, I spent several years compiling an impressive list of plants that wouldn’t grow here. Some things were obvious, like the failure of lupines which apparently won’t tolerate clay. Others, seemed more random: red morning glories, bachelor buttons, and larkspur grew to the east, but the more common blue varieties wouldn’t germinate in the west.

Eventually, some large catmints, a caryopteris, and Russian sage established themselves and I needed something to fill gaps between them that was more predictable than the ever migrating flax. Sea lavenders seemed perfect. The taproot could draw water from the narrow strip near the soaker hose, while the foot high branching flower heads could fill the dry space with tiny blue flowers in late summer.

Now, when I look at the surviving leaves, and the still green, grey or red leaved plants to the east, I wonder if my random acts haven’t revealed some hidden order in nature. Most of the plants that still have leaves fall into a few plant families: the Plumbaginaceae of the sea lavender and sea pinks; the Caryophyllaceae of snow-in-summer, pinks and soapworts; the Scrophulariaceae of the beardtongues and snapdragons, and the Saxifragaceae of the coral bells.

Ever since Darwin, scientists have been trying to detect patterns implied by such chance happenings as the survival of leaves on herbaceous plants in climates like mine. However, botanists have never fully agreed on what that taxonomy should be. In 1891, Otto Kuntze angered many of his German peers when he simply renamed many existing plants to clarify problems he found with Linnaeus’ original scheme. Sea lavender went from Statice latifolia to Limonium latifolium.

In 2003, the Angiosperm Phylogeny Group issued its own definitions based on recent findings in molecular biology, especially the characteristics of two chloroplast genes and another gene that coded ribosomes. They grouped Limoniums with the other plants surviving this winter on the east into the order Caryophyllales, which Mary Campagna and Stephen Downie had already discovered had chloroplast rpl16 genes that lacked the usual intron region associated with the development of RNA and protein.

Dolores Lledó’s team noted all the Caryophyllales were adapted to "extreme environments." Her group believes Limoniums developed about six million years ago when the Straits of Gibralter were opening and closing the Mediterranean and creating saline flats to the east. Sea lavenders, which now are associated with Bulgaria, Romania and parts of the former USSR at the eastern end of the sea, developed chalk glands which eliminated the salt they absorbed from the soil.

Ernst Benary tells growers the seeds still need low soluble salt levels in a slightly acid medium to germinate. However, the company suggests nurseries then grow the seedlings in sandy loam. I have the required loam that supports the plant in winter, but I wonder how a seedling sprouted this summer under a dripping spigot.

It wasn’t just the existence of water. When I had my well tested I discovered that the part of the aquifer which I tapped is still very salty from some ancient sea, with 78 units of sodium. Filters have reduced the count to 12, but salts no doubt collected in the area near my hoses before I acted in another random action that supports an unlikely plant within the constraints on unseen rules of natural causality in an extreme environment.

Campagna, Mary L. and Stephen R. Downie. "The Intron in Chloroplast Gene rpl16 is Missing from the Flowering Plant Families Geraniaceae, Goodeniaceae, and Plumbagaceae," Illinois State Academy of Science Transactions 91:1-11:1998.

Ernst Benary Samenzucht GmbH. "R1680 - Limonium Latifolium, Sea Lavender, Statice," available on-line.

Kuntze, Otto Carl Ernst. Revisio Generum Plantarum, 1891.

Lledó, M. Dolores, Manuel B. Crespo, Michael F. Fay and Mark W. Chase "Molecular phylogenetics of Limonium and related genera (Plumbaginaceae): biogeographical and systematic implications," American Journal of Botany 92:1189-1198:2005.

Photograph: Sea lavender leaves, 24 February 2008.

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