Sunday, August 17, 2008

Purple Ice Plant

What’s blooming in the area: Tea and miniature roses, winterfat, datura, bindweed, trumpet creeper, honeysuckle, silver lace vine, purple phlox, bouncing Bess, datura, Heavenly Blue and ivy-leaf morning glories, bigleaf globemallow, white sweet clover, velvetweed, yellow and white evening primrose, scarlet beeblossom, silverleaf nightshade, goats head, toothed spurge, portulaca, stickleaf, pigweed, zinnia, goldenrod, wild lettuce, horseweed, goats beard, Hopi tea, gumweed, spiny and hairy golden aster, tahokia daisy, farmers, garden and native sunflowers, cocklebur, sand bur, corn, sideoats grama, redtop, barn grass. Chickens let out in several hay fields after they were cut.

What’s blooming in my garden, looking north: Golden spur columbine, coral beardtongue, hartweig, squash, chocolate flower, fern-leaf yarrow, blanket flower, coreopsis, anthemis, black-eyed Susan, Mexican hat, perky Sue, chrysanthemum, yellow cosmos.

Looking east: Floribunda rose, hosta, large-leaf soapwort, pinks, coral bells, ipomopsis, California poppy, garlic chives, hollyhock, winecup, sidalcea, pink speedwell, pink salvia, pink evening primrose, Jupiter’s beard, sweet alyssum from seed, cutleaf coneflower; buds on sedum.

Looking south: Rose of Sharon, rugosa and Blaze roses, tamarix, Illinois bundle flower, Sensation cosmos.

Looking west: Caryopteris, buddleia, Russian sage, catmint, blue salvia, perennial four o’clock, flax, David phlox, leadplant, purple ice plant, white spurge, sea lavender, purple coneflower, Monch aster.

Bedding plants: Snapdragon, sweet alyssum, moss rose, Dahlberg daisy, French marigold, gazania, tomato.

Inside: Aptenia, zonal geranium, bougainvillea.

Animal sightings: Hummingbird, ants, grasshopper

Weather: Clouds hung around at night keeping early morning temperatures a bit warmer; dew Monday, rain pocked drive Thursday, hard rain before dawn Saturday and again last night; 14:05 hours of daylight today.

Weekly update: My yard has spots filled with souvenirs from failed experiments based on faulty analogies. One is that succulents are like camels: since they store water, they don’t need much. I have an impressive list of sedums, sempervivums, and ice plants that proved that wrong.

Liberty Hyde Bailey knew better in 1930 when he said succulent only meant the green parts were thick and fleshy, nothing more. Indeed, he suggested, it was a mistake to think the roots could do without water for any length of time. The thick leaves might be an adaptation to an arid climate, but those environments have rainy seasons when these plants grow and expect water.

Still, I wasn’t the first. Early in the twentieth century, railroads planted various ice plants to stabilize the edges of track beds, including yellow-flowered Carpobrotus edulis and magenta-flowered Carpobrutus chilensis. Both naturalized in Mediterranean areas of California, even interbred, to cover banks with bright daisy-shaped flowers whose parentage is too mixed to identify.

James Raulston, raised in Oklahoma wheat lands still recovering from the dust bowl, saw chilensis, or some similar Aizoaceae, blooming in southern California in 1971, when he was about 31. Later, he photographed another ice plant, an unidentified purple Delosperma, in Wisely Gardens, Surrey, in 1984.

When the great migrations from the rust belt to the south and southwest began in the 1970's, they coincided with a drought that forced cities like Denver to restrict sprinkler use in 1977 and consider how it could survive with river allocation agreements written back when local economies were agricultural. The city’s water board began promoting xeriscaping in 1978.

Raulston moved to North Carolina State where he looked for non-native species that could grow efficiently in this country. He gave potted cuttings to nurserymen who attended his short courses, including the yellow-flowered Delosperma nubigenum in 1986. Four years later he promoted the magenta-petaled Delosperma cooperi with warnings that standard greenhouse practices like daily watering and constant fertilization weren’t as useful as benign neglect.

The next year, 1991, Santa Fe imposed water restrictions that forced greenhouse owners to make water-wise choices for themselves, if not their customers. Purple ice plant was in my first Santa Fe Greenhouse catalog in 1993. By 1997, when I bought my first cuttings, the ground cover first sent to Surrey by Thomas Cooper from modern day Lesotho in 1861 was being offered by all the major mail order suppliers.

Those first plants bought in August didn’t survive the winter, probably because they went from greenhouse conditions to hot New Mexico and weren’t able to develop good roots. I tried three more the following spring under a peach, where little seems to grow. They limped along after the cold winter of 2000 and disappeared the following year.

By then I’d planted three more cooperi under a Russian sage where they got extra water whenever hose washers needed replacing. In their native range, with wet summers and dry winters, they’re evergreen. Here the narrow, triangular leaves stay green here until November, then die to the ground leaving a maze of white, woody stalks.

They don’t much like standing water in winter, and were slow to emerge this spring. When new growth did appear in mid-May, several weeks later than usual, the thick stems were deep within the shrub and have shown little inclination to spread in the face of constant winds. The glistening flower petals have also been narrower. I don’t know if they can make it through the coming winter.

The lure of a completely new succulent that blooms from late morning to dusk all summer was too big a temptation for any of us. In Farmington, Daniel Smeal included cooperi in his xeric demonstration garden, and found it couldn’t survive when irrigation levels fell below 50% of transpiration. In El Paso, Genhua Niu and Denise Rodriguez hoped the perennial would do well with recycled water and found it lost body mass. Back at Raulston’s university, a graduate student, Amy Moran, tested plants for greenroofs and found purple ice plant one of the few to fail.

I suspect they all could tell their own version of the camel, the succulent, and the eye of a needle.

Baily, Liberty Hyde and Ethel Zoe Bailey. Hortus, 1930.

Moran, Amy, Bill Hunt and Greg Jennings. "A North Carolina Field Study to Evaluate Greenroof Runoff Quantity, Runoff Quality, and Plant Growth," Greening Rooftops for Sustainable Communities Conference, 2004.
Niu, Genhua and Denise S. Rodriguez. "Relative Salt Tolerance of Selected Herbaceous Perennials and Groundcovers," Scientia Horticulturae 110:352-358:2006.

Raulston, James Chester. "J. C. Raulston's Slide Collection," available on-line.

_____. "Plants Distributed To Nurserymen - 1990 NCAN Summer Short Course," Friends of the Arboretum Newsletter (22)1991.

Smeal, Daniel, M. M. West, M. K. O'Neill, and R. N. Arnold. "A Differentially-Irrigated, Xeric Plant Demonstration Garden in Northwestern New Mexico," International Irrigation Show and Technical Conference, 2007.

Photograph: Purple ice plant under Russia sage, 13 August 2008.

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