Although it has been said that the imitation of nature is the most difficult of the arts, there is much to be gained from the attempt. Indeed, it is from nature that most good garden designers receive their creative inspiration. Careful observations of how plants arrange themselves in the natural world, and how they change with the seasons, stir designers to interpret such vignettes in abstract or realistic presentations that we call gardens.
If one looks closely, there is beauty to be found everywhere, even in the most banal of scenes. One can find inspiration in the verticality of reeds piercing the rippled surface of a pond, or in the interplay of light and shadow on plants growing at the edge of woods; even the desert-like existence of a gravelly bank reveals textures and patterns that appeal.
Although my attention is sometimes captured by a meadowy field of flowers, I am more often moved by the colors of leaves against a blue sky, in much the same way as when viewing a stained glass window illuminated by sunshine. When similarly backlit, leaves reveal that they are not all the same shade of green. There are deep greens, blue- greens, gray -greens, yellow -greens, and every shade in between, not to mention plants with reddish or wine-colored leaves. Such variation of leaf color is what adds beauty to a natural landscape, and to a garden as well. Of course, flowers usually enhance the scene as well, but they are ephemeral, to be ravished briefly before they pass. Leaves endure for months, if not longer.
Were all leaves the same shade of green, a garden would be less interesting, and would depend more upon varying shapes, sizes, and textures to stimulate the viewer. Lacking those differences, the scene would have little appeal. Think of a lush, weed-free lawn, which is, after all, a garden composed of millions of plants: it may be lovely for a moment, but quickly becomes boring, and one's view is carried to its surroundings for visual relief.
Varying shades of green enliven a landscape, by enhancing each other. Dark greens make light greens even brighter, and blue-greens bluer. It is tempting to think that these are healthy shades of green, since yellow leaves are often associated with ill health or lack of fertility. For this reason many gardeners have an aversion to yellow leaved plants. But by observing nature, we can see that some leaves are indeed yellow-green when in good health. In spring, the new growth of grass as well as other foliage is often pale green. In the full richness of summer, a maturing meadow has a lot of yellow leaves, which stand out against the bluish-green of pines. I particularly enjoy passing by salt marshes at the ocean on sunny August days, and seeing the very pale green leaves of the marsh grass against the deep blue of the sky or the gray-green of the water. In fall, yellow leaves are all around, and in winter, have you noticed how some pines on roadsides become almost golden?
When choosing plants to fill your garden, it is important to imagine plants in a garden context: a tall, thin plant may look too narrow examined at the nursery, or when viewed in a book, but imagine what it would look like in a garden, with spreading plants nearby for contrast. The differences in form are accentuated in each other's presence. Similarly, a plant with yellowish leaves may appear in need of nutrients if you have a bias toward deep green foliage, but be daring, and try putting that plant next to other shades of green. The resulting contrast confers a luminous quality on the yellow-greens, and thereby creates more interest.
There are many plants whose leaves are lighter than the norm, whatever the norm is. Many of them are variegated with yellow, creamy or white leaf portions, which I am especially fond of, but variegated plants are for another article. Most plants with entirely yellow leaves are brightest early in the season, and become closer to green as the season progresses. Some of my favorite yellow-leaved shrubs are the golden barberry (Berberis thunbergii 'Aurea', or 'Bonanza Gold'), golden elderberry (Sambucus canadensis 'Aurea' or 'Sutherlandii'). A wild new spirea with buttery foliage from spring through fall is Spirea thunbergii 'Mellow Yellow', which bears tiny white flowers in spring. For trees, try the rare but choice golden black locust (Robinia pseudacacia 'Frisia'), or the similarly textured golden honey locust (Gleditsia triacanthos 'Sunburst').
There are innumerable dwarf conifers that have yellow or golden needles. Perhaps most well known are the false cypresses (Chamaecyparis species.), represented notably by the yellow thread-leaved false cypress (Chamaecyparis pisifera 'Gold Spangle' is one of many forms). Also easy to find are golden junipers (Juniperus species.), such as the gold-tipped Pfitzer juniper. Less common, but very choice, are the golden forms of our native pasture juniper, such as the bullet-shaped Gold Cone (Juniperus communis 'Gold Cone'), and the golden mutation of the prostrate Bar Harbor juniper called Mother Lode (Juniperus horizontalis 'Mother Lode'). Golden pines (Pinus species.), firs (Abies species.) and spruces (Picea species.) are rarer still, but available.
There are many perennials whose leaves are anything from light green to golden as well. Many hostas have been selected for their rich yellow foliage, which brighten up a shady area. There are gold-leaved forms of sedges (Carex elata 'Bowles Golden', among others) which also are best for shade, and grasses which prefer sun that have yellowish leaves, such as autumn moor grass (Sesleria autumnalis), and especially the new golden form of fescue (Festuca glauca), called 'Golden Toupee'. Bellflowers (Campanula species), Speedwells (Veronica species) and other popular perennials also appear in yellow-leaved forms.
A couple of tender perennials used as annuals in our climate that have been popular lately are such plants as the Coleus, more often found with reddish foliage but there are pure yellow forms as well; sweet potato (Ipomoea batatas 'Marguerite'), with chartreuse foliage, and the yellow form of licorice plant (Helichrysum petiolarum 'Limelight'). The latter two make excellent plants for hanging baskets and other container plantings.
When using yellow-leaved plants in the garden, a little goes a long way. Just as too much of the same shade of green is dull, too much yellow can be overpowering. Try to work in different shades of green, including deep greens which act as a foil to the lighter shades, and a bit of yellow, which will make your garden appear richer, mellow, and pleasing to the eye. If you aren't sure how to find the right balance, consult a garden designer. Or, seek inspiration from all around you and see how nature so easily achieves what we all strive for. And then be daring. Go for the gold.
The previous article originally appeared in the Hollis Times, Hollis, NH.