The plants are all out there, in mail-order and local nurseries. All it takes is some advance study of perennials and their blooming times, judicious and timely mail-ordering (I know it’s hard to think September when you’re writing orders in January, but do it anyway), and visits to local nurseries at regular intervals to see what’s available.

So many garden enthusiasts rush round to the local nurseries on that First Day of Spring and assume that after that the nurseries disappear until the First Day of Spring of the next year. Wrong! They’re putting out plants, week by week, right through the season. And remember, when the last pack of marigolds has been sold, they have a lot more time to answer your questions about perennials.

In my September garden, the plants designed to bloom late provide some of the strongest elements, for many of them are relatively large, and some have commanding and dramatic presence. Something else they bring to the late garden is a freshness and a newness that enliven a scene that has by now become familiar. This is what creates the excitement in a perennial flower garden, the sense that there is always more to come and that every day will bring change.

If you couldn’t name any other flowers that typify autumn in the garden, I’m sure you could come up with “aster.” As a child, I knew these in England (where I would have liked them better if they hadn’t signaled the beginning of the school year). We called all of them Michaelmas daisies (pronounced mickle-muss), for they were the flowers that bloomed at the time of St. Michael’s Mass, the end of the third quarter of the year. In this country, they are listed as New England asters (Aster novae-angliae) and New York asters (A. novi-belgi).

Asters are marvelous flowers because no one of their rich and glowing colors is incompatible with another. I think of them as stained-glass colors, an association with harvest festivals in the local church, where they were massed against the altar rail.

In size, these asters range from twelve-inch dwarfs to towering five- and six-footers. Back in fashion now, and recognized for the beauties they are, they were at one time thought of as commonplace and undesirable. Well, beauty lies in the eye of the beholder, and the beholders of that time were dazzled by the novelty of the newly imported exotics of the Victorian era. Unappreciated in their native land, these North American asters were snatched up by British plant hunters, who took them back to England and hybridized them.

I have three particularly good performers in my garden. Aster novae-angliae ‘Alma Potschke’, has a glowing rose-red flower, blooming from August to the end of September. Aster novi-belgi ‘Eventide’, is a September bloomer of deep purple with a yellow center. Aster novae-angliae ‘Harrington’s Pink’, the tallest and latest of all, is a magnet for butterflies and bees well into October.

Japanese anemone pairs well with asters. One of the hardier ones, Anemone vitifolia ‘Robustissima’, holds its silvery pink flowers in an airy candelabrum that shows to advantage against the denser flowers and leaves of the aster ‘Eventide’. Just because I’m anxious to have late color doesn’t mean I want to put up with miserable-looking foliage all summer, so I really appreciate the handsome grapelike leaves of these anemones. They take their time appearing in spring, and they’re a bit wayward about where they emerge, but whenever and wherever they do, they’re always welcome in my garden.

The most elegant of all the Japanese anemones is a pure white that rejoices in the lovely name of ‘Honorine Jobert’. It’s a little harder to bring through severe winters and will sometimes bloom so late that an early frost nips the petals and turns them brown. But what other flowers have this delicacy and sheen to them, and where else can you find such glistening white and such silvered pink at this late date? I marvel when I pass them, and I’m grateful.

There are some thrilling dark blues in the September garden. One of them, with hooded, almost sinister, flowers (and which is, in fact, extremely poisonous in all its parts), is Aconitum carmichaelii, the purplish blue monkshood. The flowers are so dark that they photograph poorly; as an ideal companion offering a background that shows it up, I have the tall aster ‘Harrington’s Pink’, with the Japanese anemone ‘Honorine Jobert’ beside it.

A lovely deep “true” blue is provided by Salvia grandiflora pitcheri. The tubular, lipped flowers are borne on two- to three-foot stems, which either flop about aimlessly or collapse on the ground. I can’t bear to see such wands staked, so I plant this salvia close to, almost on top of, a Japanese anemone and draw the long stems up through the anemone foliage. The silvery pink and rich blue make a lovely combination.

I’ve noticed visitors stop and stare, then finger one of the blue flowers and try to trace it down to see where it comes from. The basal foliage is wretched, and, in my opinion, just as well hidden. In my own defense, I must say that it doesn’t seem to suffer from being smothered down there among the leaves of more robust plants.

Salvia is a big genus. From the southern and western United States and Mexico come many salvias that are wonderful in fall. I know, because I’ve seen them in gardens in Zone 6 and southward. Not in mine, alas.

There’s nothing like purple for richness in the late garden. The native joe-pye weed (Eupatorium purpureum) is a common sight in the wild, and there is now a German cultivar named ‘Gateway’ that is part of a favorite trio in my garden. ‘Gateway’ has purple flower heads, but even more attractive are its purple stems. Next to this is a six-foot Angelica gigas, a most dramatic plant with huge alliumlike domes of purple, starry flowers and, again, purple stems. To the front of these is a white baneberry (Actaea pachypoda), a native you’ve probably seen on walks in the woods. For much of the year it’s not an eye-catcher, but in fall—with clusters of dead-white berries and a purple-black dot at the tip of each—it justifies its popular name, doll’s-eyes.

Grown in the half shade against a birch wood, what a trio these plants make! As if the color were not enough, in a certain light their purple stems almost disappear and the flowers seem to float, lending an air of mystery to the autumn scene.

There are two late-blooming plants whose bright color might be welcome among these somber purples. Physostegia ‘Vivid’ is a cultivar of the familiar native, obedient plant, or false dragonhead, but ‘Vivid’ blooms considerably later, in a vibrant rose pink, so aptly described in its name. Chelone obliqua, the most ornamental of the turtleheads, offers bright rose purple flowers. Both plants do well in moderate shade, though they can take full sun as long as there is sufficient moisture.

If there is one color that is abundant (some might say relentless) at the end of summer, it is yellow. A lot of this color comes from flowers that are so much a part of this time of year that they are either taken for granted and barely noticed, or scorned and dismissed as boring. Perhaps it is true that familiarity breeds contempt.

In the past, I was not very charitable in my opinion of goldenrod, or the ubiquitous ‘Golden Glow’. I think there’s a good reason for that. I associated goldenrod with the bedraggled plants I used to see growing on London bomb sites during World War II—it was not a cheery sight. Similarly, ‘Golden Glow’, neither golden nor glowing, but barely surviving in sour soil at the foot of some area steps, did nothing to lift my spirits. But both of them look wonderful in the clearer, sunnier North American autumn. Why not? This is their own, their native land.

When I first came across ‘Golden Glow’, I didn’t recognize it. I was out looking for flowers to brighten the dim interior of an old barn that was to be the scene of a wedding party. With one day to go to the wedding and panic setting in, I was driving along a back road, when against an old shed I saw this wonder, a huge bush of brilliant yellow flowers. When I went to the nearby farmhouse and asked the owner if I could have some, she was more than generous. “What, that old yellow daisy?” she said, “have it all, before it takes the shed down with it.”

I filled a milk churn, barrels, and even old sap buckets with these golden flowers, and the interior of the barn came to life. Clipping some of the flowers to six-inch stems, I filled enough jelly jars for the length of all the trestle tables. ‘Golden Glow’ had to be our candles, for a naked flame was out of the question in that dry barn.

Hybridizers have been at work on both these golden beauties (you see, I’m quite converted), developing plants of more manageable size, better suited to today’s gardens. I have a most becoming little goldenrod in my garden, Solidago ‘Golden Fleece’. It grows to a mound no more than two feet tall and two feet across with compact, bright yellow flowers, attractive broad leaves, and none of the legginess associated with the taller, old goldenrods.

I looked up ‘Golden Glow’, and found it under Rudbeckia laciniata ‘Horten-sia’, where it was described as invasive and largely replaced in gardens by the superior Rudbeckia nitida ‘Goldquelle’. Of course! That must be the plant I’ve enjoyed every September for years. It’s growing next to an amethyst sea holly whose prickly, metallic flower heads show to great advantage against ‘Goldquelle’s’ shaggy yellow heads.

I’m sure there are countless gardens in late summer full of sunflowers, sneeze­ weed, tickseed, gloriosa daisies, golden marguerites, and bright yellow chrysanthe­mums. It must be a jolly sight, but I can well believe it might pall after a year or two. It’s not just that so many of the late summer flowers are yellow, but that they tend to be daisies or daisy look-alikes. Most are fibrous-rooted, fast-growing, and large at maturity, and the yellow they sport is frequently assertive.

I hang around nurseries and garden centers quite a bit, and I’m fascinated by some of the things I hear. A common question in late summer is: “Do you have anything that’s not a yellow daisy?” Well, of course they do, and plenty of them.

We’ve already considered some purples and blues. If you like bold combina­tions, just imagine what a purple aster such as ‘Eventide’ or the dark blue monks­hood could do for gloriosa daisies or any of the family of black-eyed Susans.

If these combinations are a little too much for you, you can turn with relief to the interesting whites of late summer. There is one plant I have grown for many years and which I now regard as the unsung hero of the late garden. It comes through drought, wet, and wind.

Let me introduce you to Boltonia asteroides ‘Snowbank’, a cultivar of a plant native to the eastern and central. United States. ‘Snowbank’ grows into a bush from three to five feet tall, studded with small daisylike flowers in fall. I’m a fan of this plant, as you can tell. In the first place, its gray-green leaves are a gentle presence in the border all summer long; and second, it never needs staking.

‘Snowbank’ is so strong, indeed, that it often serves to hold up the weaker brethren. I’ve seen it after a storm standing like a rock, with plants fallen into it from all sides. There is a pink form, too, Boltonia ‘Pink Beauty’, recently made available; it is lovely, blooming a little earlier than ‘Snowbank’, but don’t look to it for strength, because it is a lax grower and needs support.

Spires of flowers can give a lift to any border, and white spires are particularly dramatic in fall. Snakeroot, or bugbane (Cimicifuga racemosa), is a native that blooms in early to midsummer, but for really late bloom, Cimicifuga simplex ‘The Pearl’ is the snakeroot to have. Blooming in October, ‘The Pearl’, like the white Japanese anemone, runs the risk of damage from early frost, but it’s so lovely that I’m prepared to take that risk. It has given me glistening, bottlebrush flowers for five years out of seven, and in the other two, I simply cut off the frosted brown spikes and enjoyed the foliage.

For more white, there’s Artemisia lactiflora that begins to bloom in August. This one is not what we expect of artemisias. It is grown for its flowers and has undistinguished dark green leaves. The airy sprays of greenish white flowers at a height of four to five feet are attractive toward the back of the border and contrast effectively with more substantial flower forms such as asters and heleniums.

So much for the tall whites, but there are whites for the front of the border, too. I count on garlic chives (Allium tuberosum) for a refreshing white in August. The leaves are straplike, in a bright green that’s pleasing all through the summer. The flowers are scintillating balls of white, but before that there are the buds, and what buds! I think the beauty of some buds exceeds anything the open flowers have to offer.

These slim, sharply pointed, tightly wrapped promises are just translucent enough to suggest how intricately the florets must be folded and crumpled inside. The buds don’t all open at once, so there will be both buds and flowers on the plant at the same time. After more than a month of flowers, the seed heads on their strong stems remain a handsome feature in the border, though some garden­ers dread the proliferation of seedlings.

For the front edge of the flower, bed there is a low-growing white daisy (Chyrsanthemum weyrichii), whose thick lustrous leaves almost qualify it as a ground cover. It must be grown in full sun to flower. Don’t make the mistake I did with this latest of all fall bloomers. It was in sun when I planted it in May but by late August it was in shade most of the day, and of course needed another six weeks of sun to bring on the flowers. Once moved to a spot that guaranteed sun, it bloomed in mid-October for two years out of three. I admit this is stretching late-season blooms to the limit, but I love to see those white daisies, some of them fading to pink, among the brilliant fallen leaves.

Seeing what an ornament the wild clematis was, clambering over bushes and through the grass around the pond, I planted a sweet autumn clematis (Clematis paniculata) to cover some old posts in the garden. It certainly did what it was supposed to; every year for years it covered itself with sweet-smelling, starry flowers in October. Later its name was changed by edict, so I did The Right Thing. After all, I told myself, I have students in the garden every summer and I have to show them I know what’s what. So I pulled out the by-now almost illegible old label and put in a spanking new one. “Clematis maximowicziana,” it said. That winter, the poor thing died. Too much for it, I suppose. Grow it without a label; you’ll love it.

I count the pond’s edge planted with white iris as part of my garden, but there is a wildness there that can surprise and delight me. One September, wild clematis with quaint names—virgin’s bower, traveler’s joy, old man’s beard—trailed out from the surrounding woodland to the edge of the pond. Magically, the deep blue flowers of bottle gentian appeared at the same time. There they were—a colony of Gentiana andrewsii, little blue bottles in a sea of clematis stars, the water giving the picture back in reflection. Now there was a pure gift—no strings attached. But I could take inspiration from it, and I did. I planted a late monkshood of the same mysterious blue at the base of my autumn clematis.

I’m writing about gentians and monkshood here, in a section on white flowers, because I cannot think of any flower in isolation; I visualize each as part of a small garden scene and, if one is a newcomer to my garden, in a scene I must create. This is where my happiness in gardening lies.

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