It's not just a question of the plant's beauty, but also its performance where you are growing it.
Nothing is handsomer, in a two- or three-foot-tall way, than the blue grass Helictotrichon. I gave it a place of honor at the side of the main fish pool and for several years it was splendid, but then it went back -- the shade increased just enough to discourage it. On one side the clump of Hemerocallis citrina waxed great and on the other side some Japanese anemones started flourishing, and the competition was resented by the blue grass. It is now gone.
Back by the garage I had another ornamental grass, the striped Miscanthus sinensis variegatus, which rose to 10 feet with its longitudinally white-marked leaves. One spring I dug it up and moved the main clump four feet back of its original site, against a garage wall. It has not really flourished since. It now grows to six feet and no longer flops on a path (the reason for moving it), but the base of the garage wall is drier than its original spot and the grass resents this.
It is important to remember when you plant something against a wall that the site is probably more dry than you think. Extra watering, especially the first year, may be in order. And even when the plant is fully established, it may miss the wetter conditions of the open border and, like the striped grass, restrain itself. Of course, this may be all to the good.
You might wonder what to do when a favorite plant weakens or dies. You can replace it, obviously, but in the case of my blue grass there would be no point in that, since it failed through competition from other plants near it and from a slight increase in shade. I shall do nothing, but let the daylily and anemone fight for the space.
On another side of the pool there is a strip three feet wide and 12 feet long running against the raised side of the pool. There are some wild native swamp irises in a clump, and for a while there were some foxgloves and bunch primroses. They all got tired -- they need renewing by seed or division every year or two.
It was an ideal site for the yellow moneywort, except the moneywort did not know it and refused to grow. Some eau-de-cologne mint wandered over from its home 20 feet away, and some wild buttercups with their varnished yellow flowers have appeared. A lovely weed, except that after blooming it dies away and the ground is bare in the summer.
What could be grown in such a space, dampish and half-shady, between brick pavement and the concrete wall of the pool? Well, if I moved the wild irises out (Iris versicolor from a local swamp) and dug in a barrow full of leaf mold and some peat moss and let it all settle down nicely, I could grow Kirengeshoma palmata. This is a perennial posing as a small shrub, growing three feet or so, with leaves like a Norway maple's, and hanging yellow bell or trumpet flowers in October. I have never seen a photograph of it that would make anybody desire it. And yet I never heard of any gardener who, seeing it in the flesh, did not want it.
It's not the leaves and it's not the flowers -- it's the way the plant is put together with such refinement and freshness. Well, it could replace the wild irises. Then there is a raised brick step that should be kept clear of plants, though sometimes cymbidiums in their pots are stood there for the summer over my dead body. Beyond, the narrow planting strip continues. I shall certainly keep the clump of merry-bells (Uvularia grandiflora), one of the prettiest of our woodland plants. It shoots up in the spring with foot-high stems decked with leaves like a solomon's seal and a set of hanging pale-yellow bell flowers at the top. It blooms in April, then dies down. It will not stand competition from other plants jammed up against it.
All the same, I am considering several plants for this strip. The virulently poisonous veratrums are all desirable, including our native V. viride. They boast pleated, broadly lance-shaped leaves in spring, and possibly no other garden plant rivals them in beauty then. Unfortunately, slugs like them even better than hosta leaves and the veratrums can soon look ratty with holes in them. And as the spring and summer progress, the leaves can look more and more weary. When fully established after a few years they send up a flower stalk to four or five feet, packed with tiny flowers that are insignificant, but because of the masses of them along branched stalks they are conspicuous.
Especially desirable is V. nigrum, with flowers that look almost black.
The plant is extremely hard to find (Wayside Gardens, Hodges, S.C. 29695, catalogue $1, has it for $8 each) and you have to weigh its slow growth, often ratty appearance in summer, against its singular beauty of leaf in spring.
Some of the smallest astilbes would also do in this spot, especially A. chinensis pumila, which reaches two feet in height, with feathery magenta plumes of flower in summer for some weeks. The color will not suit those who dislike magenta, but the foliage is divided like a coarse fern.
If you wanted to be reckless, you could try the taller A. taquetti superba, which reaches five feet with great feathery magenta plumes. I once noticed it in a Maryland suburban garden blooming with daylilies and coveted it. I have heard this plant called Spirea superba. For general purposes, for most gardeners, probably the commoner Lythrum 'Morden's Pink' will serve as well to provide the small blast of magenta desired (by me, at least) with daylilies.
The plant formerly known as Megasaea and now Bergenia is the one with cabbage-like evergreen leaves and (sometimes) magenta flowers of no great consequence in the spring. You grow it for the foliage. It is especially handsome against stone, and since it sits right on the ground like a cabbage, you want to give it a forward position.
I used to grow the esteemed variety called 'Ballawley Hybrid,' which loathed the dry shady spot near a box bush that I chose for it, having seen it doing nicely in England in such a site. Here I think it can stand a bit richer living and more water.
A chief point of today's remarks is that there is never any shortage of wonderful plants to try, even if a favorite plant in the garden dies. There will never be time or space enough to explore the riches of garden plants. I have no connection with Wayside, or any other nursery, and pay for plants like everybody else, and complain loudly when I get poor plants by mail, as I sometimes do. But what a delight to see Wayside stocking the veratrum and some rodgersias and the less common astilbes and so on. In the past I have mentioned these plants to them and maybe enough of us have done so that now they sell them. It is much easier than ordering them from England.