Friday, May 2, 2008

Adelphi Front Bed With Iris, Penstemon, Coreopis auriculata nana, Germander, Sporobolus et alia

It does look good in this picture! Many of us have had, some regularly, the experience of looking at pictures of our gardens and knowing that they suggest a garden much nicer than the actuality. As though we were defrauding with photography. Well, yes and no. I know that if you had been standing with me when I took that picture, you would have seen a patchy asphalt street in the foreground. And lots of cars. And the sketchy turf surrounding the pictured island bed, and weeds in other beds. But still the plants in the picture were beautiful.

I use my garden, and others, as mnemonic devices, useful tools when I am designing and need to be able to call plants to mind quickly. Among the beauties here are several that are quite functional in the landscape. Iris pallida Aurea-variegata, the variegated iris center foreground, is a useful accent in a small mixed planting as it is here. Or, if you add two more of the same plant and position them in other beds in a pleasing triangle, they can help unify a small area, like my (or your?) front yard. Like many monocots, it has an architectural structure that visually isolates it (even without the variegation) from the more random growth of the dicots, i.e. the Germander to it's left, the Penstemon in front of it, and the Coreopsis behind it. Variegated Iris used to be fairly uncommon, but now are available inexpensively at both box stores and mainstream nurseries. Other variegated forms you see fairly regularly are Iris pseudacorus Variegata and Iris pallida Variegata.

To the left of the Iris is Germander,Teucrium chamaedrys, an evergreen sub-shrub. Of course I love sub-shrubs so I am predisposed to favor this plant, but any honest person would have to admit that its useful and beautiful. Like the other evergreen herbs, it is happiest in hot, well-drained soil, and full sun. No wonder this one is so happy, rooted in sand in a sunny bed beside a blacktop road! It doesn't grow much over a foot high and the evergreen leaves provide structure and interest in the winter. Much of the summer it is covered with rosy pink flowers that look like they belong on a plant in the mint family, which, of course, this is.

Everyone wants to grow herbs but everyone doesn't have a sunny sandy bed. A different place you may have that wiould serve these plants well is a SE or SW or W facing strip, against your house, overhung by your roof line. The herbs appreciate the hot reflected light, even more if it is beside a driveway, and the overhang helps keep the soil dry during wet periods. Lacking either of these areas, try a container in full sun (at least 6 hours).

The beautiful grass on the right is a native plant Sporobolus heterolepis, Prairie dropseed. Its characteristic rounded form and narrow, dark green blades make this distinctive grass a great garden plant. It tolerates a wide range of soils, clearly happy on sand. It is drought resistant in full sun, and though it browns in the winter, it retains enough of a presence to use as mass plantings in highly trafficked, highly visible areas. I have heard that Native Americans ground the seeds for "flour." I have watched the birds eat them in the winter.

Thursday, May 1, 2008

Its about the light. Its always about the light.

Except it isn't really; sometimes its about the smell and sometimes its even about the touch but thats not common. Once in a blue moon its about the sound, like wind in bamboo, or the rattling of Baptisia seed pods. Of course with fruits and vegetables and herbs (and lots of other stuff with George) its about taste, but I still keep coming back to the light. My favorite light is early morning sun. I like to face the sun but not have it in my eyes; then it lights up the plant you are looking at. If there's dew, like in this picture, the drops refract the rays like prisms. Early light is soft and forgiving and the plants themselves often look better in the morning. Usually they are hydrated, turgid, recovered from whatever sun stress impacted them the day before.

Still, it isn't just the time of day and the quality of the light. The direction makes a huge difference. Look at a clump of dewy grass with the sun obliquely behind it, it glows. Then walk to the other side, that is, past the plant towards the sun, and look back at the same plant. No magic. Well maybe its still a beautiful plant but its halo is gone. No glow from transmitted light. Just the plant itself and I don't mean to belittle any plant, but we all like to be seen in our best light.

Which brings me to my next point, "don't smoke crack." Oh wait, thats an obscure reference to an Adam Sandler movie (Waterboy) that I ought to be ashamed to have watched, except for that one quote....Really my next point is that we have the luxury in our own gardens of taking maximum advantage of our light. As a designer, I make every attempt to position plants to maximize their appearance in relation to the sun, but if you are there 365 days a year you will understand the subtle nuances of your particular lighting better than I can and make those significant minor adjustments. There are so many variables; the path of the sun changes throughout the year and so the angle of the sun changes. In the winter when the sun is low in the sky, the shadows it creates emphasize textures. Sharp shadows forcibly delineate bark furrows, masonry surfaces, moss, even fallen leaves. The ambient color of light changes; in summer green foliage makes green light. The cloud types that the sun shines through change all the time but the thin cirrus haze is sort of particular to winter. Deciduous shade comes and goes with the seasons. And on and on. I imagine it is possible to spend a lifetime in a small garden and not exhaust all the possibilities.

If you are really interested in making your garden its best, spend time in it. You have to see it morning, mid-morning, noon.... and on to dark every day of the year. And in sun and rain and mist and snow and ice storms. You can introduce elements into your garden to maximize its beauty in an ice storm! I don't know if I have ever been in a garden that had reached the level of completeness where that was a reasonable goal to strive for but you know, there is that belt of states running E/W: North Carolina/Tennessee/Arkansas where they always seem to have ice storms...That's silly maybe, but the point is that while it may be a luxury to be able to spend time in your garden, its also a responsibility.

( on the picture)

Wednesday, April 30, 2008

1000' of Nylon Cord and Some Used Plastic

You never know when you're going to need large quantities of used plastic. This afternoon; George (fellow gardener in Conifers and Dogwoods), Joan, and I covered the Fern Valley pond with plastic. I wasn't sure we could do it but darn it, look at the picture! To celebrate May Day (just kidding) gypsy moth caterpillars are being targeted and selected wooded areas at the Arboretum are being sprayed with Dimilin, an insect growth regulator. We covered our pond to protect the aquatic larvae of dragonflies, damselflies, and other good insects. Beech Spring Pond, the largest pond at the Arboretum will not be sprayed, but since the Fern Valley Pond is so small and overhung by trees it will be significantly hit by the chemical.

I am not an unquestioning supporter of the use of chemicals, but the gypsy moth population has obviously been rising steadily for several years. In Fern Valley, we ring some of our most susceptible trees with burlap bands and "harvest" the caterpillars that hide there during the days. We record the numbers per tree per day and this provides an informal method of assessing relative levels from year to year. We knew things were getting bad and when a more systematic analysis suggested that the risk level had been exceeded by an order of magnitude, the decision was made to spray. The chemical of choice, Dimilin interferes with chitin synthesis, preventing insect larvae from growing and so resulting in their death. All studies have shown that there are no negative effects on humans or other higher animals. The frogs and turtles are safe!

Personally I am glad to see this spray happen. In Fern Valley and around the Arboretum, Oaks, trees of choice for gypsy moths, have clearly suffered over the last two years and the number of egg cases last year was frightening. It is likely that a significant side effect of this spray will be that cankerworms, those tiny green or yellow inchworms that drop on you in the woods all summer, will be hit hard too. I have watched the numbers of these increase for at least 10 years. With no scientific or experimental confirmation, it appears that the increase is linear rather than cyclic, and related to decreases in the population of warblers and vireos. Unfortunately these decreases are documented. I remember when cankerworms were not a serious issue but now, every year they seem to be more and more a problem; I hope a significant hit this time of year can bump them back to acceptable levels.

This sure is beautiful, and life sure is complicated

I got to the Arboretum just after 6:00 this morning so I went some places I don't always go. This is the Camellia section of the Asian Collections. The sun is rising over the Anacostia River which is at the bottom of the slope that begins at the back of this picture. The beautiful blue flowers drifting through the middle of the picture are Hyacinthoides hispanica, Spanish Bluebells. This is a geophyte in the lily family native to the Iberian Penninsula..

This picture illustrates why the question of native and non-native is so complicated. Undeniably, we are looking at a beautiful plant that you and I have every right to grow in our gardens. The fact is though, that it moves steadily and inexorably into wild areas adjacent to gardens. Is this bad? I think so but I don't know for sure. If it is bad why is it bad? I don't know. Wouldn't the world be prettier with more of these bulbs in more woods? Clearly, but would it be a better place? Wow! It is difficult to picture this tiny plant overturning a native ecosystem, but the world is a complicated place; remember Homer and the donut (the butterfly effect). The ecosystems that we inherited are the result of millions of years of complex co-evolution. Their structures are incomprehensibly complex and interdependencies are critical. When we pollute them we destroy them degree by degree. It is a one-way street, a street I, personally, don't think we want to continue down. There may come a time in the distant or not so distant future when our descendants look back and wonder how we could have been so short-sighted or so selfish as to allow so much to disappear.

There aren't always good substitutes for beautiful non-native plants, but in this case we could achieve an equally stunning effect by using Phacelia, Mertensia, or Phlox divaricata. If your back garden abuts a tributary of say, Rock Creek Park, and you still feel a compelling need for this plant, consider using it in the front garden and watching it. Don't let it get out back!

Tuesday, April 29, 2008

Dramatic Native Vine...Lonicera sempervirens

There are any number of spectacularly beautiful native plants but for some reason there is a tendency on the part of their advocates (myself included) to be a bit defensive faced with 1000+ years of selection of Peonies, Rhododendrons, Camellias, Roses, etc. We have lady's slipper orchids, and trilliums, and our own Rhododendron spp., and hepaticas and a plethora of stunningly beautiful flowers but still sometimes, to be confronted by hundreds of blooming Tea Roses, German iris, Asian Rhododendron cvs., and Chinese Wisterias all at the same time it is a bit overwhelming.

Anyway, this is a native species, the Coral or Trumpet Honeysuckle, that doesn't have to take a back seat to any exotic cultivar. Plus it is inexpensive, easy, flowers heavily in April or May, depending on where you live, and sporadically the rest of the season. It is the quintessential hummingbird flower; the tubular corolla, the color, and nectaries too. I have always (well for 35 years anyway) grown this species. It is native from Connecticut south to Florida and west to Texas. It clambers through shrubs and trees to ~20'. In the bed adjacent to the Fern Valley parking lot, on the far side, the plant in the picture climbs to over 15'. There is a yellow variety, Sulphurea, that grows equally well; at the bottom of the Fern Valley Road, we have a nice plant sprawling through a Fragrant Sumac, Rhus aromatica. The sumac flower heads are yellow themselves and the two plants make an interesting composition in early May. While it doesn't have a fragrance like Japanese Honeysuckle, it doesn't overpower native vegetation by the acre either.

Coral Honeysuckle is one of a handful of plants that I kept in Florida through the massive de/relandscaping. It tolerates those very dry conditions (it did finally rain .22" after 3 weeks yesterday!), and is equally happy here with more rainfall. This honeysuckle is widely available and inexpensive; for less than $20 you can likely get a flowering plant now. Plant it in any soil where it can climb into the sun and it will be happy forever.

Monday, April 28, 2008

April Showers bring April Flowers

After two years of off and on drought conditions we have had plenty of rain this spring. More than 2" fell on the 20th and 21st; one week later we're looking at another 2+ inches. More than we really need, but right now, when the leaves are expanding, is a good time for it. Growth is explosive. Walking through Fern Valley, branches, many laden with flowers, invade the paths. If we didn't prune regularly, the paths would soon be impassable.

The rain is good for newly planted grass; spring isn't the preferred season to plant grass in the Washington area (fall is) but if you went for it this year, you hit the jackpot. Likewise, if you planted trees, shrubs, or perennials this past fall you are still on Mother Nature's Dime as far as watering is concerned. Thats why fall planting is safest. The most problematic season for newly planted plants is summer so if you plant in the fall your plants have 6 months or more to grow roots and establish themselves before it gets hot and dry. If you go to the Nursery on a nice day in May, summer might start the next week and if not will surely appear within a month and a half. It doesn't mean you can't plant in spring; you will just have to pay more attention to watering needs,

In this photo Rhododendron periclymenoides, the Pinxterbloom Azalea in the foreground is one of hundreds in Fern Valley. This is the commonest azaleas in the Piedmont of Maryland and Virginia. It is an easy plant to grow, handling deciduous shade, a variety of soil conditions, and various moisture levels.

Sunday, April 27, 2008

It says "Nursery" but it is really a Box Store

They do sell a lot of plants though. I have to admit I was there this weekend. The landscape crew needs 3 Compact Japanese Hollies to match an existing planting. They were not to be had at Behnke's or Homestead so.... I got three 3 gallon plants at the pictured emporium, for only $12 each. They were very overwatered but I expect that that happened at this site and since they had likely only been there a day or two or three, they could dry out and recover.

The retail Nursery business is an interesting phenomenon now. The big box stores, like this one, use the buying power generated by their giant sales to drive their wholesaler's pricing down. They don't take great care of plants, but since their stock turns over so quickly it doesn't matter. You can get some good deals if you buy before their maintenance regimen has a chance to damage the material. Having said this though, to be fair I have to observe that the box stores are raising their prices. "Specialty annuals" for 3-4 dollars a 4" pot is not bad but not great either. Its about what most Nurseries charge. $15,00 for a 2 gallon deciduous azalea ('Gibraltar) is good, but $60.00 for Pinus flexilis Vanderwolf's Pyaramid in a 3 gallon pot is what real nurseries charge. They're still a good place to find a bargain if you know your plants and understand whether a particular plant is healthy or not.

I worked at the FONA plant sale at the Arboretum on Friday and went back Saturday. It was so crowded I just drove on by. I got some great stuff on Friday though; Crinum x procerum 'Sangria', Hosta Mouse ears', a dwarf Aqueligia canadensis, Sisyrinchium ? 'Suwanee' (maybe a new species) and a few other odds and ends. FONA also sells used books; they are alway good but this year they had the bulk of two incredible personal libraries. The books were wonderful but the experience of buying them was bittersweet.

On Saturday I planted. The plants came from everywhere. Some were hanging around after being brough back from Florida, some from FONA, a few hanging around from the Lahr sale, some were dormant in the basement, one from Behnkes. Wow. I didn't know I had this much space.