Light and Shadow

As all of my former horticulture students can tell you, photosynthesis is the process of transforming carbon dioxide and water into sugar and oxygen in the presence of light. In plants, mostly. Yes, that’s a simple way of describing a whole lot of complicated biochemical processes, but that’s it in a nutshell. Of course there are horticultural implications arising from all of that elegant botanical metabolism, the most important being where we as gardeners care for a plant in our garden, greenhouse, or living room: full sun? almost dark-closet shade? somewhere in between? I could go on about the significance of photosynthesis to us gardeners, but that’s not what is calling to me as I write this. Instead, I’d like to share some photos and thoughts about light and shadow as elements of garden design.

Let’s begin in a public gardening space: Citygarden, which is described on its website as “an urban sculpture park located in downtown St. Louis.” I visited it while enjoying a Lakeshore Technical College Horticulture Club field trip ‘way back in April 2016. The sun had recently risen and the shadows were strong, making the plantings and numerous sculptures eminently photographable. I stopped to admire this large metal piece, not only for its (to me) flowerlike subject matter but also for the dramatic, ephemeral, and constantly changing shadow-and-light shapes it produced in concert with the ascending sun. If I had returned to this spot even a few minutes later, those protean “forms” would have been different if not completely gone from the landscape. Transience, for good or ill, is unavoidable, whether in a garden or more broadly in one’s life. Which takes us to the next photo . . . .

. . .  of this stone pool at the edge of the splendid Japanese Garden at the Missouri Botanical Garden , photographed a few days after the Citygarden visit. Like the Citygarden photo, there’s not a lot of strident color jumping out here, but note how form (shape) again plays an important role, expressed by physical objects and the interplay of light and shadow. Did you notice the strong rectangular pool first, or did the interplay among the rounded forms of the cherry blossoms, river stones, mouth of the water spout, and light-and-shadow ripple pattern initially catch your eye? I’d say the stone pool simply provides a frame for the far more engaging “picture” it surrounds. How about you? And you realize that the river stones and stone pool were not physically striped, but instead the stripes were constantly changing as the shadows and light moved over them, right? How would this setting appear differently on an overcast day?

Now let’s return to my home town of Sheboygan, Wisconsin, specifically to Bookworm Gardens , one of the crown jewels of this part of the world. Billed as a children’s garden, its appeal is definitely not limited to kids. I took my horticulture students to Bookworm many times, and I return frequently during the May-to-October season. It’s filled with big and little attractions to encourage visitors to interact with its plants, structures, and non-human denizens. While leading an early evening tour at Bookworm this past August, I happened to notice an unusual pattern of light and shadow in a patch of a large-leaved groundcover. Upon closer inspection (translation: getting down on my knees for a better look), I figured out that the cut-out metal label for this planting was producing a backlit light show on the leaves of Bergenia, AKA Pig Squeak. Do you see the “Pig” and the initial fragment of “Squeak” written in light and framed by shadows cast by the label? As in the previous two examples, this little bit of magic would be gone in a few moments as the sun continued to set.

I can’t get enough of strolling through my front garden on warmish summer nights. One of my favorite night spots is this area in front of the steps into the house. The pole-mounted garden lantern, sitting above the top of this picture, projects a pattern of light and shadow through the metal base, adding extra detail to the concrete slabs that make up the walk. Of course the light also brings out the colors of the plants and mulch, but I find the angular light-and-shadow “shape” is the star of this show. In case you’re wondering, that gorgeous little bit of blue below the chartreuse Heuchera Primo ‘Pretty Pistachio’ is Corydalis flexuosa Hillier ‘Porcelain Blue’, which I intend to discuss in detail at a later date. In the meantime I’ll be attempting to come up with the perfect adjective for that shade of blue.

Standing just a few feet to the north of the lantern is the new fence, custom-made last summer from cedar and dreams. There’s an entire photo sequence of the construction of this assertive garden element and its companion to the south waiting to be presented on this website, but let’s look at the light-and-shadow interplay here. I think the sharply contrasting angular “forms” of light and shadow created by the afternoon sun, acutely interacting with the rails and posts, make just as potent a design contribution as the posts and rails themselves. I know you see the piano keyboard-like pattern toward the top, but did you notice the other two rows of light and shadows at the bottom? They aren’t nearly as emphatic as the top row, but they certainly add to the composition. As with all of the other photos presented in this post, I invite you to consider what this picture would look like in the absence of strong light.

I leave you with two garden compositions composed primarily of shadows, both taken in the back garden on the brilliantly sunny, warm afternoon of August 1, 2019. The first consists of the shadows of prairie plants projected onto the concrete walkway that divides the two sections of my little prairie garden.  You’ll need to scroll down to learn the identities of the plants, because I think you should ponder the beauty of both images without the fog of plant nomenclature clouding your sensory perceptions. I don’t have much to say about either photo, other than to invite you to contemplate the design importance of light and shadow in a garden and to encourage you to get lost in your own memories of warm, sunny, pleasant summer days.





Here are the names of the principal shadow-plants in the first picture:

Veronicastrum virginicum (Culver’s root) with pointy leaves widely separated on the stems

Echinacea pallida (pale coneflower), two daisy-like flowerheads

Zigadenus elegans (the inelegantly named mountain death camas), several clusters of smallish fruit.   The correct scientific name for this plant – which I discovered as I was confirming the plant names for this post – is now Anticlea elegans. Now do you understand why I didn’t include the plant names in the description above?

The shadow-plant in the second photo is Senna didymobotrya (the very evocatively and spot-on, aproposly named popcorn plant, the leaves of which beg to be gently stroked to release the fragrance of slightly burnt buttered popcorn). The solid, rounded shadow is produced by the large container required to help this species attain an impressive (6-foot) stature in one season.

I WILL grow coleus this year!




Funny thing, my relationship with coleus. You know, those common, colorful foliage plants that seemingly everybody includes and enjoys in their containers and plantings all season long. Everybody but me during the last few years, that is, because (this has been my excuse for the past few years) it’s just too cold where I live, a mere few blocks from Lake Refrigerator Michigan here in Sheboygan. They have failed to grow in my front yard, and they performed poorly in the little patio garden at Lakeshore Technical Garden, where I once taught. After the plants I was overwintering gave up the ghost in the LTC greenhouse, I too gave up and haven’t grown them since.

So you’re thinking, “Yeah, so? They don’t like you, or maybe it’s true that the cool lakeside summer nights aren’t their thing. Nobody succeeds at growing everything.” Well, plenty of gardeners around here grow coleus – even closer to the Lake, I might add – and well. Why not me? It bugs me, as you probably have already figured out.

You see, there’s something going on here that could be considered the dictionary definition of the word “irony.” I literally wrote the book on coleus, namely Coleus: Rainbow Foliage for Containers and Gardens (Timber Press, 2008). Producing the book was a joint collaboration with my friend Richard Hartlage; I did the words, and he did the photography. Amusing side note: if you detect a subliminal reference to how people often partner up to create Broadway musicals, may I point out that Coleus was produced by Ro(d)gers and Hart(lage)?

Anyway, while making Coleus happen, I got all caught up in growing them in a big way at Atlock Farm in New Jersey, so that Richard could photograph them and I could study and make notes on their characteristics. Richard and I even made a visit to Minnesota to learn at the feet of Vern Ogren, a major figure in the history of coleus in the United States, and we also traveled to the home of Bob Pioselli, a major collector. Along the way I branched out into exploring other ways to promote or simply enjoy coleus, as the following pictures illustrate.


This picture was taken of me while I was serving as American editor for The American Horticultural Society A to Z Encyclopedia of Garden Plants (Dorling Kindersley Publishing, 2006). I was preening what was the most impressive standard (tree-form) coleus specimen ever produced at Atlock Farm. You can see a photo of it, minus yours truly, in the Encyclopedia.







Yes, I had a coleus jigsaw puzzle made from a group photo I took in front of one of the greenhouses at Atlock. It’s still with me, but I haven’t put it together in quite a while.









Sometime after taking this picture of ‘Freckles’ (one of my favorites). . .









. . . I sent off a file of the picture to a company that custom-weaves cotton throws. The bright colors of ‘Freckles’ weren’t reproduced in the throw, but the overall pattern always catches my eye.








Timber Press had mouse pads made as a promotional item for the book, and a few of them remain in my collection, not of mouse pads (does anyone use them these days?) but of coleus stuff.








By now you realize that coleus are a part of me and my history. That’s why I’m trying my hand at making them happy again. This time around I’m going to do a little experimenting: since I’m assuming my past attempts failed because of too-cool weather, I’m going to try to give this year’s plants as much heat as I can provide. The warmest – no, hottest – part of my garden is the concrete slab that adjoins the west house wall, and that is where I’m going to place three good-sized, sturdy-walled, black plastic storage bins. The rays of the sun and the re-radiated heat from the concrete and the black containers will, I hope, provide the warmth that coleus want from me. Of course I’ll need to choose sun-tolerant cultivars, and I’ll keep a close eye on the moisture in the potting mix. With any luck, I’ll also need to routinely supply fertilizer to my lustily growing success stories outside the back door.


In early June the three black bins will be planted with sun-tolerant coleus (and probably a few cannas or other taller growers). The empty space between the leftmost bin and the invisible concrete steps is being set aside to accommodate a large standard Pelargonium ‘Mabel Grey’ (lemon geranium), which will serve as a focal point when looking toward the house from the sidewalk that runs between the prairie planting in the back yard.

With any luck this scheme will work, and there WILL be coleus to enjoy this summer, especially on Saturday, July 13, the day my garden is a stop on the Sheboygan Area Garden Walk.

Stay tuned!