PVC Bulletin May 2006






Potomac Valley Chapter

North American Rock Garden Society



Volume 8, Number 3


May  2006



This bulletin is a bimonthly publication of the Potomac Valley Chapter, NARGS

Jim  McKenney, Editor jimmckenney@jimmckenney.com 301-770-1867


Calendar, 2006  


May 20, Green Spring Park, our Plant Sale Merry Bruns, Dixie Hougen and Jim Dronenburg have volunteered to organize this. Now it's up to the rest of us to provide some good plants. Check this website periodically during the upcoming weeks for more details.

May 27, Alice Nicolson, "Alcova", our Plant Exchange

Plant Exchange on Saturday 27 May, at Alice Nicolson's in Arlington. Coffee at 9:30; plant exchange begins at 10 a.m..  We  will bring what is left from the plant sale the week before at Green Spring, and members will, hopefully, bring the usual extras from their gardens. Please do try to label the plants and put your initials on the back of the label, so people who are interested in the plant will know whom to ask about it. As usual, try not to bring invasives, or at least label them as such.. Bring plants, stay for lunch and a board meeting. Bathrooms are being remodeled, so be prepared for a work site!
.Directions as follows:

"Alcova", 3435 S. 8th St., 1 block from Glebe Rd., between Columbia Pike and Arlington Blvd., in Arlington.

Directions. From Alexandria, take Glebe Rd. N to S. 8th St. Go Left on 8th one block, to “Alcova”, the first house on the right beyond the Methodist church. You may park in the church lot or on the street.

From DC: Cross 14th St. Bridge and follow Rt. 395 to Glebe Rd exit; go Right (N) on Glebe and follow above directions. OR, take Roosevelt Bridge and follow Rt. 50 to Glebe Rd. exit; turn Left (S) on Glebe to S. 8th St. or the church parking lot just before, and go Right.

From 66. Follow Rt 66 in to Glebe Rd intersection; go Right (South) on Glebe about 1 mi. to S 8th St or the church parking lot as above.

From MD West; take Beltway to 66 inbound to Arlington; follow directions above.

If these instructions leave you baffled, call or email for more directions - 703-979-5871 or taxonomy@speakeasy.net


June 24, the Botting's in Gaithersburg, Md.,, our summer picnic meeting . Check this web site in mid June for more details.

Next Deadline June 15, 2006


New Members

Welcome to the following new members:

2006 Adams Luci 2006 13130 Copper Brook Way Herndon   VA 20171 703-793-7008

2006 Bradford Betsy 2006 114 W.Alexandria Ave Alexandria   VA 22314 703-549-2289 btsbrdfrd@aol.com

2006 Canale Peggy 2006 2805 Ridge Rd. Alexandria   VA 22302 703-549-6979 pcanale@attglobal.net

2006 Ganley Betty 2006 5206 N. 32nd St Arlington   VA 22207 703-536-1644 elizabeth.ng@verizon.net

2006 Huber Joan E. 2006 1017 Fowler St Falls Church   VA 22046 703-533-9579

2006 Hagan Leslie 2006 419 E. Howell St Alexandria   VA 22301 703-548-4665 73144.560@compuserve.com

2006 Harmon Virginia 2006 610B Thayer Ave Silver Spring   MD 20910          vharmon@aoc.gov

2006 Hyatt Don 2006 1948 Lorraine Ave McLean   VA         22101 703-241-5421  Don@donaldhyatt.com  (?)

2006 Landis Michael 2006 P.O. Box 10187 Alexandria   VA 22310 703-329-1908 mplandis@att.net

2006 Lassiter  Anne 2006 202 High St         Alexandria   VA 22302 703-549-7690  maclas@comcast.net

2006 Monje Sandy 2006 12435 Kemp Mill Rd. Silver Spring   MD 20902 301-625-5951




Weldenia candida, a Mexican alpine in the Washington, DC area


Weldenia candida is an elegant alpine. It also happens to belong to the family of plants, Commelinaceae (dayflowers and spiderworts), that I study professionally. Until now I have considered it ungrowable in our area mainly because of our summer heat. What follows is an account of our recent and past experience with the plant.

In January of this year I was given a plant of Weldenia candida by Terry Partridge. The plant arrived bareroot and dormant. We potted it up and kept it dormant in our basement. Just after I returned from Kew in mid March we remembered that we had not looked at the Weldenia pot in a long time.  Much to our surprise, the plant was not only alive but in active growth, having produced a three inch stem above ground with a chalice-like swelling at its apex.

As soon as we found the Weldenia plant in active growth we moved it outdoors, placed in it a wire, squirrel-proof cage on our deck and started watering it. Growth was slow, especially on warmer days.  Two days ago, on April 18, the plant produced its first flower, which surprised and elated us.

Weldenia candida, the only species in the genus Weldenia, is native to the mountains of central Mexico and Guatemala, occurring up to 14,000ft (4500m) elevation. It produces a rosette of leaves, usually at ground level, with a central boss of 1" wide, brilliant white (rarely pale blue in forma caerulea) flowers that have a very narrow tube up to 2˝" (6.5 cm) long. The vertical stem, from the bottom of which arise numerous tuberous roots, can be up to a foot (30 cm) long and is normally completely subterranean. The stem of our plant is partly above ground perhaps because the plant started growing in the dark and the pot was rather shallow.

In 1976, when I worked at the Field Museum of Natural History, Chicago, we collected Weldenia on a research trip to Mexico. We tried to grow a plant in a greenhouse at the University of Chicago, where I kept my other research plants, but it went into dormancy without flowering and never came back. We attributed the plant's demise to the heat.

Having a flowering plant of  Weldenia just outside our back door is very exciting.  I have already made one observation that I have not seen in the literature.  The flower stayed open for at least 24 hours.  No other Commelinaceae flower would have lasted nearly that long.  I look forward to learning more about this plant.
Can we grow Weldenia here?  From my discussions with Terry I am somewhat optimistic.  He told me that when he grew it in England, he kept it in a pot, and when the plant went dormant, after flowering, he would bring it indoors and not water it again until the following spring.  In our area survival may depend upon whether the plant goes dormant before the summer heat sets in. Time will tell.  Pot culture would seem to be essential here.
A couple of final notes about Weldenia.  Terry says that the plant can be propagated by root cuttings, but it takes a long time.  We are trying.  The ovary in the Weldenia flower is often underground, as in Crocus.  If seeds are set, the pedicel (stalk) of the fruit elongates as the seeds mature, pushing the fruit, a dry capsule, aboveground, where it splits to release the seeds.
Bob Faden
20 April 2006

Here's a link which gives some illustrations of Weldenia candida:




Our Plant Sale at Green Spring

Our chapter will sponsor a sales booth at the annual Spring Garden Day, May 20, at Green Spring Garden Park.  This event has been well attended and has provided our chapter with an opportunity to introduce gardeners to rock gardening and earn money for speakers, by selling member-donated plants.  We need plants to sell.  If plants are not donated, we cannot make money.  Some people fret that they have nothing rare to donate.  Do not worry.  Few of the people we are trying to reach  know rare.  Maybe we think that because we are pulling out the variegated Polygonatum , everyone has it and no one will want it.  Pat yourself on the back for being able to grow a plant well that others need to lighten up a dark corner of their shady garden.  However, it would be a disservice to the gardening community to pot up weedy sedums and difficult-to-eradicate Houttuynia cordata.  Please use botanical names on labels.  I am trying to make a "cheat sheet" for chapter members who will be working at our booth.  I would like to list as many plants as possible so horticultural advice can be given to potential buyers by member-helpers who do not grow the plant.   Please, please, please bring plants.  If you can, let me know what you will be donating so I can add it to the "cheat sheet".  If you cannot bring plants the day of the sale, please call (703.360.3948)or email me (taos11@verizon.net) and arrangements will be made.  We can't make money unless we have plants to sell.  Directions to Green Spring can be found in the link below.  Thanks.                                                                                       D. Hougen


John Lonsdale, March 12,  2006

Marion Jarvie, April 1, 2006


When I was a teenager, my interest in opera really burgeoned. This was back in the late '50s and early '60s, what some of us nostalgically think of as the last, great golden age of opera. One tuned in to hear the Saturday Met broadcast, and the singers - just to name some of the ladies - were the likes of Nilsson, Price, Tebaldi, Callas, Sutherland. It ruined me for life: it's been downhill ever since. What does this have to do with our speakers? Betty had Janis Ruksans scheduled for our March program; Ruksans broke a leg (not in the theatrical sense)  and had to cancel his North American speaking tour. If you were running an opera house, and your star performer cancels at the last minute, what would you do? That's the challenge Betty faced, and the solution was brilliant: John Lonsdale agreed to step in on short notice. Keen as I was to hear Janis Ruksans, it was a pleasure to hear John. This was not his debut performance with our group, and I hope there will be many more. He has a growing and  well deserved reputation as a successful grower of difficult and highly desirable plants. Furthermore, since he gardens only a couple of hundred miles up the road, his comments and experiences have a particular relevance to our local conditions. He treated us to a enviable array of Dicentra, Cyclamen, oncocyclus and juno Iris, Lewisia, Stellera, Daphne, Trillium and others.  John's soft voice combined with his British accent were the source of some merriment in the back rows where we were having trouble hearing him. He had shown a slide of Muscari macrocarpum, very well grown, so well grown that my first impression was that it was a Lachenalia! As he gave the name, it sounded like "microcarpum" to some, and for several minutes the back row crowd twittered sotto voce as some queried microcarpum? and others corrected macrocarpum! like so many high school students furtively swapping answers during  a test. John also brought some plants for sale, plants you're not ever likely to see in the local garden center. The turnout for John's presentation was very light; much of the Mall area was closed off that day for a race and the US Botanic Garden was nearly inaccessible by car except by those not daunted by authority - or was there an official "entrance" to the Mall area that day? Let's hope John comes back soon.


Marion Jarvie gave a well received presentation based on her experiences in her one third of an acre garden in Toronto, Ontario. I once heard it said of a certain author who went on to a distinguished career in international relations that "he got a lot of mileage out of his bachelor's degree" (the point being that he never went on to graduate school). Marion Jarvie certainly gets a lot of mileage out of her one-third acre! Jarvie is a delightful speaker, at times conspiratorial, almost always good naturedly skeptical and humorous. She did a great job of presenting herself - she was only a bit into her talk before I realized how much I liked her. Her garden showed a nice balance between the collector's instincts and good design sensibilities. This was not the garden of the "high alpinist" - it was like our gardens, the garden of a generalist with a nod in the direction of the rock garden. It certainly seems to be a beautifully groomed garden. The suite of plants she presented was drawn from the repertoire of mostly smaller plants, many of them either new to cultivation or to the nursery trade. Her slides gave us a nice mix of close up shots and broad views. The layout of the garden and the careful placement of woody plants of notable foliar effect combine to allow views which seem improbable in such a small garden. There were lots of good lessons here about plant selection, plant culture, plant associations and the overall placement of plants in the garden.                                                                                           Ed





Saturday April 29 dawned bright and clear, an accurate presage of the day ahead for those of us who took the chapter's spring bus trip. Two gardens and a stop at a nursery proved to be a good combination. The nursery was Asiatica, and Barry Yinger put out an irresistible array of gourmet plants which caused this visitor - and most others, too - to forget the diet and stuff up on wondrous delicacies. Eat, drink and be merry, for next month we'll pay the credit card bill. The little box I filled looked so innocent; the bill was stunning! We had two hours for this feeding frenzy; I'll bet that those who sent in their orders beforehand left with even more than they had ordered. Those of us who did not send in our orders were little better off than those hapless souls who go grocery shopping when they are hungry; I didn't see anything which didn't look good. To judge by the overflowing boxes others carried around, there were a lot of hungry shoppers that day. It would have taken nerves of steel to get out of there without dropping a C note; more than one person was heard to rationalize it by saying they were spending the $100 the government is giving us for gas money. At any rate, it was reason enough for me to run back and grab another Asarum. What's that old Latin aphorism? Hortus  longus, vita brevis?

The two gardens we visited made an interesting contrast. On the one hand, the fifty acre Appell estate, Millbourne, offered a handsomely developed site expressed along traditional lines for properties of this importance. The ten acre West-Kline site was a woodland garden set in a natural woodland setting, and other than a minimally obtrusive residence, development in the usual sense was utterly arcane. Different as they were, these two sites had something in common: each was a creek valley, the one largely tamed, the other largely as nature made it. And each had mill associations.  

The bus parked outside the Appell estate, and we walked from the bus approximately three hundred feet up the long driveway to the residence where cookies and a guide brochure with a map of the property awaited us. As we approached the house, it hit me: I suddenly felt that I was "in" a special space. It was the fragrance of the spruces which scented the air and produced a sort of olfactory embrace and welcome. If you have spent any time reading pre-WWII  books which discuss site development for properties of this stature, you felt right at home in this one. Yet the property as it now exists was evidently developed much more recently, beginning as recently as 1985.

 We were on our own, and I had spotted a glowing patch of blue through a break in the spruce screen and headed in that direction. The blue turned out to be Pholx subulata, and it marked the entrance to the Secret Garden. I found a place to sit and proceeded to enjoy my lunch - and was soon joined by several others who had the same idea. This Secret Garden was only one of several amusing conceits in this garden: there is a tower,  a made ruin in the old tradition of garden follies,  part way up the ridge which apparently is one edge of the property.  Across the valley formed by the little creek, on a high spot, is a small stone chapel whose site provides another broad view of the site. The tower was open for those willing to climb the ridge and the stairs. The door to the tower and another door to a lower level in the tower (a dungeon?) were both worth close examination, handsomely wrought as they were of iron and wood.

Near the residence a small space was intensely developed and planted: this is the King Edward's Garden.  A small statue if the eponymous king overlooks this long narrow space, at the time filled with tulips and other late spring color. The statue of the king faces an opposite wall with two verdigris medallions: we puzzled over these, but were finally able to make out the names of Washington and Franklin on these. An espalier Viburnum on the connecting wall was just coming into bloom with huge globes of greenish white sterile flowers. Just above the level of the King's Garden is a well-done square of pleached limes (lindens) which define another charming sitting area.

The watercourse which runs through the lowest level of the garden is dammed at the upper level to form a small lake with a boat house. The shape and mass of the low boathouse is mirrored on shore by a comparably sized mass of Japanese butterbur. On one side of this watercourse is a long (several hundred feet long) straight walk lined with, among other things, thousands of Virginia bluebells. These were at their peak during our visit.

The slope opposite the house boasts a fine conservatory with attendant changing rooms for the nearby pool. A sunk garden is being developed nearby. The upper parts of the slope have extensive rhododendron plantings. A section of walk here has a broad curb of Hedera colchica. A very lovely walk lined with two broad blue-spangled bands of periwinkle (I wouldn't want the job of weeding those, but they were undeniably charming) takes the walker on to areas planted with roses and peonies and other traditional flowers.

Gardens often seem to fall into one of two opposites: indifferent plants beautifully maintained or plants of great intrinsic interest indifferently maintained. The Appell estate succeeded in providing plenty of beautifully maintained plants, some of them of intrinsic interest. A pergola on one side of what is called  Flora's Garden was draped with the white-splashed foliage of Actinidia kolomikta. In Flora's Garden itself, a broad ground cover of Mazus reptans provided a bright patch of color. A low flight of stone steps was bordered by what at first glance seemed to be ivy; on closer examination the ivy revealed itself to be the ivy-leaved cyclamen, Cyclamen hederifolium. It was certainly earning its name, and absolutely no apologies need be made for the job it was doing. A pinetum was spread out over the top of one ridge near the Chapel. Low rock walls draped in Saponaria ocymoides and Campanula made me wish for a chance to visit the garden again later in the season.

Two down and one to go. For the West-Kline garden the bus again parked on the street and we walked in. These brief strolls in give one the chance to readjust to the new surroundings. Here again we were in a small creek valley, the property extending roughly from ridge line to ridge line and thus providing a wonderful sense of seclusion in this long narrow site. What look like natural rock outcroppings were in fact carefully built of imported local stone.

We broke up into two groups, West taking one and Kline taking the other. As long as the groups were close together, some of us jumped back and forth from group to group as particularly interesting plants came up for discussion. Wide groups of Phlox subulata bloomed in the soft light, and here and there we stopped to spar over the identity of a tuft of foliage. A low artificial bog provided some of the first hot plant sightings: a clump of Helonias bullata caught my eye, and there was a something else unfamiliar. This turned out to be the Veratrum-relative Stenanthium gramineum . It would be worth a return trip later in the year to see this one in bloom. This bog area was separated from the main path by a substantial trough with, among other things, a lovely pale yellow Rhododendron keiskei hybrid. Morris explained the function of this trough: it was there to keep people from backing their cars into the bog! By now major plant ADD had kicked in, and it was hard to stay in line so-to -speak. Some bright green broad foliage caught my eye: Veratrum nigrum doing really well, and apparently only six years old from seed sown in-situ.

In other parts of the garden, unfamiliar little leaves poking up prompted some queries: these turned out to be Mertensia sibirica. On a dry wall, some rosettes of green turned out to be those of Ramonda myconi; up the hill a bit, in a dry wall more  dark green savoyed foliage turned out to be that of Ramonda-relative Haberlea rhodopensis (or was it H. ferdinandi-coburgi?). This same wall had nice plants of Camptosorus rhizophyllus, the walking fern. The walk up to the house was bordered by troughs here and there. It was a pleasure to puzzle over the contents. Earlier in the visit, downhill so-to-speak, some of us had been discussing the dwarf rock garden iris, among them Iris minutoaurea. There in one of the troughs was a fine fat clump of this little yellow iris. Higher up the hill, the excitement grew: a softly luminous patch of blue turned out to be Anemone nemorosa. A tiny spot of red emerged as Trillium pusillum. Pachysandra stylosa came in for some discussion, perhaps because several of us had obtained plants earlier in the day during the nursery stop. A wet spot on the hillside hosted a plant of Lysichiton camtschatcensis.

And then there were the Glaucidium palmatum. Big clumps here, scattered self-sown seedlings there, white ones, some almost murrey - just as we got over the excitement and envy of seeing one group, another would appear as if to mock us. These Glaucidium prompted numerous hushed confessions of spousal deception in the form of credit card abuse and other recitations of regret and dismay. How many of us had tried and failed? How much had we spent? And here they were, popping up left and right like weeds in the moss.

Running along much of the length of the garden is a long open space which parallels the creek: this is what remains of the old township road. That much is known for sure; there is speculation that the road may have pre-Revolutionary War origins or even have been an old Indian track, perhaps an Indian track following a deer path (it's hard here to resist a bit of reductio ad absurdum: should we continue the speculation back to the days when our antediluvian ancestors hauled themselves up out of the creek, perhaps this very creek...). At the downstream end of the property there is an opening in the woods; the moss covered ground is sprinkled with violets and Panax trifolius and volunteer seedling Veratrum viride. This opening in the woods looks so natural that it comes as a shock to learn that the site was once a dump, literally a dump. After the dump was cleaned out, West and Kline used the site for camping during weekend visits before the house was built. Back in those days they were weekend refugees from busy lives in Baltimore. Now that world they left behind comes to them.                                                          Ed


 Use this link to bring up the   IMAGE PAGE  which has images from the Robin and from our bus tour.