Ithaca Journal Article: Hostas For Your Garden

Hostas For Your Garden
By Mary Hirshfeld

Have you been thinking about growing hostas in your garden? These natives of Japan, China, and Korea have a long history as cherished garden plants in Japan. They are now developing a similar history here!

Hostas were slow to make their way into European gardens. The first two species--the still-popular, sweet-scented August lily (H. plantaginea), and the dark purple-flowered H. ventricosa, arrived in the late 1790s. But the real European interest in hostas began in the 1820s after Philipp von Siebold, a physician working for the Dutch East India Company in Nagasaki, brought a cache of hostas back to the Netherlands. Von Siebold was an avid horticulturist and spent his spare time seeking out horticultural specimens for his Nagasaki garden. He managed to amass a collection of over 5,000 plants, some collected only as dried herbarium specimens and some maintained as live plants that he took with him when he was expelled from Japan. Among them were the statuesque blue-leaved Hosta sieboldiana, the narrow-leaved H. 'Lancifolia' and the white-striped H. 'Undulata'. Originally categorized as species, both 'Lancifolia' and 'Undulata' are now considered cultivars, since populations have never been found in the wild. Perhaps they originated as mutations of a wild plant, or as a result of garden hybridization.

Interest in hostas as garden plants languished until a new influx of plants became available from Japan in the 1950s. The 1960s were years of increasing interest in hybridization, and exploration of the tremendous diversity in leaf color and form that the genus offers. The critical discovery was that variegation can only be passed on by the maternal(pod) parent-- so crosses using a variegated paternal (pollen) parent would not achieve the desired results of a range of new variegated patterns to further refine.

Hostas are divided into categories based primarily on leaf color: green, blue, gold, and variegated. They are also categorized by size: mammoth, large, medium, and small. This system streamlines the selection process, allowing gardeners to easily select plants for a specific color combination, site, or use. Examples of hostas from each of these categories can be found at Plantations throughout the groundcover collection, Comstock Knoll, and the Deans Garden (a shady garden tucked behind Warren Hall, north of the Ag Quad).

The green group may initially sound like a pretty dull group, but there are some striking plants in this category. 'Lakeside Black Satin', as its name implies, produces glossy black-green leaves on a medium-sized plant. In a different size category, 'Leather Sheen' is a small eye-catching hosta with bright green leaves that look as though they'd been recently waxed and buffed to a high sheen. 'Komodo Dragon' offers rather plain, wavy-margined green leaves but what makes the plant unusual is its mammoth size-three feet tall and six feet wide! Like many plants of enormous stature, 'Dragon' is a slow grower and Plantations' young specimen is still working its way towards its full size potential.

The blue and gold groups offer a number of durable landscape and specimen-quality cultivars. Both colors will tolerate quite a bit of sun, the gold becoming brighter, and the blues more green as sun intensity increases. Hosta sieboldiana is a parent of many of the large-statured blues and provides its offspring with powder blue leaves with an interesting puckered textured. However, it also has rather poorly shaped pale flowers held on stubby spikes, which detract from rather than add to the plant's beauty. Many gardeners simply cut the flower stems off before they have fully developed to maintain the visual integrity of the sumptuous clump of blue leaves. Large blues of specimen quality include 'Big Daddy', with its cupped, very puckered blue bright blue leaves; and 'Blue Umbrellas', which forms a huge clump of rounded leaves held high on long petioles, like small umbrellas. 'Blue Cadet', essentially a smaller, grayer version of 'Big Daddy', makes an excellent showy groundcover.

My favorite gold hosta is 'Sum and Substance' a mammoth with thick golden leaves that tolerates full sun with no ill effects. At the other end of the spectrum is 'Gold Edger' a very useful groundcover that is rhizomatous, spreading by underground stems to quickly form dense weed-proof colonies of bright, foot-tall yellow-gold leaves.

Because of its size and complexity, the variegated group is further subdivided into more specific categories. The variegated margin group has a green leaf center with a lighter colored margin. The variegated center or medio-variegated group has just the reverse: a pale center with a darker margin. And the irregularly variegated group has a dark leaf background punctuated by stripes, streaks, dots, blotches, or other asymmetric markings. The different variegated groups have received the most attention lately from hosta breeders, and many stunning plants have recently become available at reasonable prices.

Growing plants in this group does require some patience. With the exception of the variegated margin group, patterns may require several years to stabilize, and young plants do not display patterns of variegation typical of a mature four- or five-year- old clump. 'Francee' is an excellent variegated margin cultivar with rich green puckered leaves edged cleanly in white. 'Fringe Benefit' offers a soft green center with a rich yellow margin. And 'Great Expectations' is one of the best in the variegated center group, with an irregular yellow center darkening towards the margin to green. It is a large plant and an incredibly slow grower that has taken six years to reach its potential in the Deans Garden--but it was worth waiting for. The irregularly variegated group has some real oddities. Like the variegated center group, they can be unstable, producing atypical leaves until they reach maturity. 'Spilt Milk' is a good example of this category, with blue leaves splashed and stitched with white, as if a glass of milk had been flung over the leaf.

Another interesting direction in recent hosta breeding is the selection of plants with large, well-shaped, fragrant flowers. True, hostas have not traditionally been thought of as choice flowering plants. But today, careful selection can bring fragrance and even hummingbirds to your garden in August. The August lily (Hosta plantaginea) is a wonderful species that, along with a clump of lilacs, often graces the foundation plantings of older homes. As a parent, it provides its offspring with both fragrance and large flower size. 'Royal Standard' was one of the first of this group and remains one of the best for ease of cultivation, speed of growth, and durability. A mass planting of 'Royal Standard' comprises part of the steep northwest-facing slope on Comstock Knoll, delighting visitors with its spires of crystalline white flowers and heady perfume. 'Gold Standard' sports yellow leaves edged in green and similar white flowers, although it isn't as floriferous or vigorous as its parent. 'Fragrant Bouquet' offers apple-green leaves with a pale yellow margin and white flowers. One of its offspring, 'So Sweet', is a smaller version, whose flowers carry faint purple stripes. Then there is an exotic double-flowered selection of the August lily, called H. plantaginea 'Aphrodite'. Plan a visit to the cool, shady groundcover and rhododendron collections on a hot August afternoon. Your efforts will be rewarded with the sweet sights and fragrances of H. 'Honeybells', 'Summer Fragrance, and 'Sweet Susan'-hostas that have truly earned their names!