ROCK GARDEN QUARTERLY VOLUME 54 NUMBER 4 FALL 1996 COVER: Penstemon rupicola 'Diamond Lake' by Paul Martin of Golden, Colorado All Material Copyright © 1996 North American Rock Garden Society Printed by AgPress, 1531 Yuma Street, Manhattan, Kansas 66501 ROCK GARDEN QUARTERLY BULLETIN OF THE NORTH AMERICAN ROCK GARDEN SOCIETY formerly Bulletin of the American Rock Garden Society VOLUME 54 NUMBER 4 FALL 1996 FEATURES Pinks and Gilliflowers: An Introduction to Dianthus, by Nancy McDonald 267 Small Honesties: Small Fragrant Pinks, by Rand Lee 287 Daphne arbuscula: An Encounter in the Wild, by Joan Means 293 Daphne arbuscula, Its Biology and Distribution, by Peter Turis and Olga Erdelska 296 Daphne arbuscula: Notes on Forms and Hybrids, by Fritz Kummert 301 Growing Five Siskiyou Treasures, by Phyllis Gustafson and Jerry Cobb Colley 303 Siskiyou Lore, by Ramona Osburn 311 Lewisia megarhiza: Forgotten in Mexico and Guatemala, by Burl L. Mostul and Miguel Chazaro 317 Canons of Rock Use: A View from Victoria, by Atholl Sutherland Brown 319 DEPARTMENTS Awards 326 DIANTHUS SYLVESTRIS 266 ROCKGARDEN QUARTERLY VOL. 54(4) PINKS AND GILUFLOWERS: AN INTRODUCTION TO DIANTHUS by Nancy McDonald JL he pinks that inspired my infat• The American Dianthus Society uation with Dianthus are neither alpine In 1991, Rand Lee went looking for nor perennial; they are not fragrant an American Dianthus Society to join. nor even particularly showy. Deptford There was none. Frustrated by the lack pinks (D. armeria) had naturalized in of information about pinks in many the fields around my childhood home, general gardening references and by escaped perhaps from some settler's the relatively few plant choices avail• garden. The tiny, hot pink stars of able on the market at that time, Rand these annual British natives joined wrote a letter to Organic Gardening chicory, Queen Anne's lace, and ox- magazine, mentioning his interest in eye daisies in being flowers we were forming a society. Seven people allowed to pick; their one- to two-foot responded. The first bulletin was an stems provided satisfying lengths for eight-page, stapled newsletter called bouquets. Now, decades later, I still The Gilliflower Times. (The G is soft, as rejoice to see those blazing sparks in in the name Jill. Gilliflower is the old the tall grass of our orchard and even name for a number of scented herba• welcome the occasional specimen into ceous perennials, including pinks, the wilder parts of our garden. stocks, and sweet rocket.) For the first Later in childhood I met sweet two years, Rand himself largely williams (Dianthus barbatus) growing financed the non-profit society, which near an old farmhouse. As a young had 100 members by the end of the adult I encountered the old fragrant second year. By the end of the third cottage pinks and tiny, prickly alpine year, there were 250 members, and buns. Once I had seen them, I could membership has stayed around that not let them go. So when I saw an figure ever since. Dues now cover announcement in National Gardening almost all costs. The Gilliflower Times Magazine that the American Dianthus has doubled in size and contains arti• Society had recently been formed and cles and letters by members, excerpts was seeking members, I sent them a from historic documents, and Rand's check and found I was the eighth per• wonderful Dianthus Encyclopedia, son to join. which covers (usually) one letter of the 267 alphabet per issue. Two round robins The iris bed wasn't much of a suc• travel the country; indeed, one sails cess as an iris garden, and it hasn't around the world to an Australian been much of a success as a dianthus member. New members from all test garden either. I did everything nations are most welcome. wrong that could be done. Knowing that pinks require good drainage and The Northern Test Garden aeration, I did nothing at all to the soil, My husband Ira and I garden in which is certainly free-draining, but is Zone 4b, in far northern Michigan. We also acidic and poor. It grows beautiful wanted to grow more pinks and were moss wherever a plant gets tall enough frustrated to find how little informa• to shade the surface, but the pinks tion there was about cold-hardiness of struggle along with minimal nutrients the various types. In addition, much of and low pH. Pinks in general do not the available information seemed require high alkalinity; neutral soil is incorrect, judging from our own gar• fine for most. However, our native sur• dening experiences. In 1993 we decid• face soil tests 5.5-6.0 pH. Acidic soil, ed to begin systematically testing provided it is well-drained, will not kill species and cultivars of Dianthus in most pinks, but they fail to thrive in it, our gardens, checking both for cold rendering them easy prey to the first hardiness and for optimal soil mixes. disease, frost, or insect that comes The pinks we grew already were along. Amendment with lime or lime• scattered in various garden beds stone gravel is a simple thing, if only around our property, each with its one knows enough to do it. own microclimate and slightly differ• My next mistake was to choose seed ent soil. In order to better compare and mixes such as Thompson and contrast the behavior of the plants, we Morgan's Rockery Mix, rather than decided to build separate beds in just individual species. Many lovely little one area. Two existing garden beds plants have resulted from that and were cannibalized and expanded for other seed mixes, but I haven't the this purpose. They lie side by side faintest notion what they are. I imag• northwest of our house and receive ine they are second-generation plants very nearly full sun. Our native soil is from named cultivars: fine for the gar• essentially sand, with the merest nod den, but useless for testing. In addi• at loam, and extremely acidic. Wild tion, because of the garden's odd blueberries, notorious lovers of acid shape, it's almost impossible to get soil, thrive in an unmown area just a close to individual plants to compare few feet from the dianthus test beds. them with others. And I failed to map The first bed we took over was full my plantings, so when the deer held of bearded irises, and we called it the evening dances (or whatever it is they Iris Bed. We still do, though all but the did) on top of the garden and lost or standard dwarf irises have been destroyed the labels, even those few removed; it seemed too much of grind identifiable species became muddled. to change the name in all my notes This garden is scheduled for renova• and records, so the Iris Bed it shall tion next summer; I shall move the remain. It is a raised bed, the sides pretty pinks to other garden beds formed of very large glacial rocks that where the exact name is immaterial, we dig up everywhere here. In shape and start afresh. it is between a kidney bean and a lop• The second bed, the Zephyr garden, sided triangle. has been much more of a success. It 268 ROCK GARDEN QUARTERLY VOL. 54(4) was named for Zephyr, the god of the 3 Kstrmtria rufaa UtiftSi. West Wind, because it is one of the Broad leafed Sweete Williams. westernmost beds in our mowed area. I later learned that in Greek mytholo• gy, Zephyr was the husband of Iris. He was the rival of Apollo for the love of the beautiful youth Hyacinth or Hyakinthos—which provides a name for the next bed of the test garden. The Zephyr is long and narrow and further divided into seven smaller beds, separated by straw paths. Each smaller bed is raised, with large rocks surrounding it. All pinks are close enough to the paths to be admired, compared, and smelled with ease. Each section is mapped as it is planted. Small plastic labels are buried north• west of each plant; in addition, large zinc labels are set out during the growing season, so the plants are read• very well rotted compost, and one part ily identified by visitors (and us). And, limestone gravel has proven to be best of all, the pinks seem abundantly excellent. The sand and gravel provide happy with the soil mixes we have perfect drainage and aeration; the made for them. limestone provides an antidote to our To ensure that we're comparing acidic soil, and the compost provides apples with apples, we try to grow nutrients and enough water-retention pinks with similar size, habit, and cul• to keep the plants happy even during tural needs together. Thus one section dry spells. Despite the gravel, the beds is devoted to tiny alpine buns; another are full of beneficial earthworms. For contains Dianthus gratianopolitanus and the beds containing the smallest, fussi• its cultivars; another is devoted to est alpines, we add an extra part of heirloom garden pinks, and so on. limestone gravel, making that compo• We're still in the process of refining nent one half of the soil mix. To sup• these divisions. Unfortunately, we've ply further soil conditioning and per• already run out of room in several of fect drainage around the crown of the the sections, so a couple of sections plants, all beds are mulched with a contain a mix of plants. To avoid a layer of limestone gravel. This is par• pest-attracting monoculture, about a ticularly important for the alpine third of the plants grown in the test pinks.