Saturday, April 18, 2009

Plumbago europaea: a good plant from the Azerbaijan trip




This is one of the plants that Stephan Lura collected in Azerbaijan last fall. It's flowering nicely in the greenhouse now but according to the literature is hardy to USDA Zone 6. Since it was collected from an area with hot and humid summers and cold winters, it ought to love the east coast at least as far north as Philadelphia. This seems to me to be a plant that could be of some horticultural value. Apparently P. europaea has been in cultivation in Europe for some period of time. I see it described as a purple mound of fragrant flowers late in the season. And its tough. Sounds good.

Stefan reports that he has germinated, if I remember correctly, over 80 of somewhere around 100 taxa collected: a good percentage by anyone's measure. A number of these plants are interesting because they represent rare wild collections of common plants, many herbs, that have been in cultivation "forever." That's a great thing and quite exciting to a very few people. It seems to me however, that there are a few taxa, the Plumbago among them, that may be of more widespread interest.

The region that this trip collected in has been a glacial refugium, an area to which southward creeping glaciers have "pushed" northern plants. As the glaciers receded northward topographic isolation (by seas and mountains) has "trapped" large numbers of taxa. Because the area is isolated, over time evolution has produced a large percentage of endemics: an interesting flora and one we want to investigate. This trip was a good start. We're trying to create gardens that require fewer "inputs", i.e. water, fertilizer, pesticide, and general coddling. This flora from a "tough climate" could yield some useful plants.

Viola pedata 'Eco Artist Palette'....Wow

The cultivar section of Fern Valley has acquired some cool plants this year. This one isn't out yet, but it won't be long. This is a selection of Viola pedata, the Birds-foot Violet made by yet another Georgia super-horticulturist, Don Jacobs.

Viola pedata is a variable species; in the trade it is commonly seed grown so if you shop for it you certainly ought to see the plant in flower. Some are distinctly and brilliantly bi-colored, others, though still beautiful, are much less striking. This one (not seed grown) is over the top! Because it's asexually propagated, any plant named 'Eco Artist Palette' should look like this. I dont know this particular cultivar, but some somatic mutations are not completely stable and there can be variability in a group of plants that are "genetically identical." This looks like that type of variation, but again, I don't know this cultivar!

One of those plants that is particular about where it grows, the Bird's-foot Violet prefers to live in a well drained area in full sun. I remember being amazed years ago seeing them happily growing on the margins of a dry dirt road in West Virginia. They seem so delicate! Be careful about overindulging them. I have a clump in my front bed (pure sand and full sun) that I never water and it has been getting bigger and bigger for years.

Rosa primula: the first rose to bloom in China Valley this year

There are buds on quite a few roses already, but this is the first one to actually flower; Donald Wyman observes, in the 1986 edition of Wyman's Gardening Encyclopedia, that it was the first rose to bloom at the Arnold Arboretum among a collection of more than 100 species. Rosa primula is commonly called the Incense Rose because of its fragrant foliage. I don't note a strong fragrance here, but the flowers are pleasantly, though lightly scented. The foliage is attractive and clean (of course it's early!), growth is strong, and there are many buds and many flowers. It's easy to find; it is growing at the top of the bed just a few feet below the road above China Valley.

Honestly this is not a rose I know particularly well; Stefan Lura, who was an ASRT in China Valley before he moved to the position of Botanist in the Plants Records Office, planted a good number of Chinese Roses in the collection. most uncommon, some downright obscure. I can hardly wait to see the rest.

Thursday, April 16, 2009

Stylophorum diphyllum: Wood Poppy...ambitious self-seeder colonizes Fern Valley

Wood Poppies are cheerful and deer-resistant, two good qualities. Members of the Papaveraceae, the Poppy Family, they contain some interesting and potent chemicals that color their sap yellow, and which deer don't enjoy consuming. Easily grown, the seeds from one plant often produce enough offspring to eventually naturalize throughout an entire garden...in a good way. They like semi-shady areas with good soil and adequate moisture, but will adapt to less favorable situations, peforming at a slightly less spectacular level. During the summer they normally cease flowering, but extended rainy periods can induce a new period of bloom.

Deutzia ningpoensis: new leaves

Hey, this is a hand-help photograph taken with a $300 camera. How in the world can I see cells, nuclei, and vacuoles? Optics have come a long way since my first camera! This is a nice shrub, a Deutzia, still...nice. Branches arch attractively. The flowers are white. It received the RHS "Award of Garden Merit" in 2004.

Syringa spp. cvs. xs....It smells good this week at the Arboretum


Lilacs: if they're not you're favorite plant, I bet they're in the top ten!

Curiously this is the same day, April 16, that I posted the Lilac collection at the Arboretum last year. I didn't do it by intent, I just noticed the date when I was cutting and pasting, i.e. plagiarizing, myself. I'm not lazy, I just did such a good job the first time it seems a shame to waste it. Anyway this part is new. Like the cherry fields, the lilac nursery contains both the plants acquired to provide germplasm for the breeding program, as well as some of the plants produced by that program. There are a couple of acres of lilacs across the road from the Capitol Columns parking lot and continuing down the hill. You can't miss them.

While visitors aren't actively encouraged, the area is open and if you don't pick the flowers, and obey all the other rules you are welcome to walk through. Certainly feel free to inhale. (One of the most important rules is no parking on the grass. It may seem counter-intuitive, but park on the road to the side!) This is a collection you ought to see at least once! Most of the old-fashioned cultivars prefer to grow farther north than here; our summer heat, humidity and heavy soils combine to create an inhospitable situation. I feel like I have a good grasp of how most things horticultural work, and I can't explain the existence of these plants; there is no other equivalent collection this far south. (Having spent a year thinking about this problem, I suspect that the "tough love" policy of Susan Greeley, their caretaker, as regards water goes a long way to explaining why these plants are as happy as they are. They expect to be dry in the summer and Sue cooperates.)

Wednesday, April 15, 2009

We got a good bit of rain on Wednesday...the plants like the rain and I like the muted colors



I just drove around the Arboretum on the way home and photographed from inside the car. It was drier that way! I wonder why the Birch on the left is so much more advanced that the two to the left of it?

I guess the Bluestem is not so muted, but its a wonderful accent all winter and it's still looks great. It's a warm season grass, so it's just ignoring all this rain and waiting for soil temperatures to rise. The smallish tree in the background is Quercus virginiana the Live Oak; while they are evergreen farther south, this individual generally drops all its leaves some time during the winter.

Tuesday, April 14, 2009

Aquilegia flabellata nana-Yezoense: an easy re-seeding (redundant?) Columbine

There's something endearing about this dwarf Columbine; its shortened spurs produce a clunky flower lacking the sinuous grace that defines so many of its relatives...still its cheerfully appealing. I had Aquilegia flabellata nana alba, the white form, for years in my garden where it reseeded, true to color, interestingly but not invasively. At some point the seedlings became all blue and white, but I found I liked them better. Eventually, as happens with reseeding species, a year came when they didn't come back at all. Its good to see them at work! They're flowering right at the front of the Asian Collection this week.

Trochodendron aralioides: I knew I liked this plant

I admired the dehiscent syncarpelous fruit of this plant this past winter; look! the buds, actually the bracts enclosing the buds, are pretty spectacular too. I knew I wasn't shallow enough to fall for a one-season plant. This individual is in the Asian Collections at the USNA; it'll still be nice this weekend, a very cool plant. It's obtainable from a few places, none, so far as I know, local. Forestfarm, on the west coast, lists two sizes in their online catalog. They carry an extremely wide range of usual and less-usual plants. I have never had any problem with them, save the fact that shipping is fairly high (but, I assume, fair). They're a good resource through which you can often obtain the obscure plants featured in garden magazines.

Sunday, April 12, 2009

Dyschoriste oblongifolia looks great in Florida despite cold winter and no rain


The Florida garden shrunk considerably over the winter. Neighbors who spent the winter said it was the coldest they could remember....of course, like myself, they're old. Still it was a cold and a dry winter. A few plants died outright; many more died back to their roots. The problem with root-hardy shrubs in Central Florida is that the rains don't come until June so a lot of regrowth doesn't happen in spring. Sure there were small tufts of foliage where the Firebush had been, and the Duranta, and the Lantanas, and the Strelitzias, but most of the regrowth wont happen for another few months.

Some things made it through unscathed; the Simpson's Stopper is an incredible plant, Psychotria nervosa is budded and beautiful, Salvia greggii cultivars were cheerfully attracting butterflies as were the Southern Butterfly Weeds. But Agaves burned by 20-odd degree cold!!??!! They'll be back.

Epimedium lishihchenii...the Epimediums are flowering now: these leaves will be spectacular long after the flowers have gone!

Shortia galacifolia...this is the one we transplanted. It is waiting patiently for the seedlings from the collecting trip

There are still Shortias flowering in Fern Valley! The garden is supposed to reopen this week so everyone will be able to see them.