Hostas are currently the number-one selling perennial in the country.
From the family lily (Liliaceae), the genus Hosta is native to Japan, China and Korea. In these countries they are often found in woodlands and near water.
In North America, hostas are found in just about every state with the exception of the southwestern states, where heat and lack of moisture tend to be a problem. Although they do grow in the south as far as Georgia, Tennessee, and Louisiana, they grow best where they can experience a period of cold dormancy, such as in our own Minnesota.
Terminology
There is some debate, but there are roughly 40 species of hosta from which all varieties, cultivars and sports come. Examples of species are H. tokudama, H. sieboldiana and H. montana. A “variety” signifies a distinct group that, while still being a part of the same species, varies slightly, often exclusive to a certain geographical area.
The term “cultivar” means a cultivated variety—a plant that was developed in cultivation, not the wild. An example would be a hybridizer making a specific cross of two plants, each with desirable traits, to obtain one plant with all of those desired traits. (Cultivars names are marked with single quotes, such as ‘Halcyon’.)
A “sport” is a mutation. An example would be a solid green hosta that has a leaf or two that may be streaked or have a yellow edge. That portion is a mutation of the original plant. It was not hybridized—something just happened in nature to cause the mutation.
Made for Shade?
Often labeled a shade-loving plant, hostas are truly more of a shade-liking plant. The definition of sun and shade varies—a lot! A hosta friend of mine once put it this way: the opposite of sun is not shade. The opposite of sun is dark. Nothing grows in the dark. Shade is part dark.
While hostas can do well in shade, they can also do well in a much lighter environment. The amount of light that hostas should receive is dependent upon the climate. In Minnesota, hostas will tolerate more direct sun than those grown in the south.
Basically, hostas prefer the less intense morning light, and an area with bright, dappled sunlight with one to two hours of direct sunlight each day would be an ideal setting. Since hostas don’t like heat (some varieties will want to go heat dormant when temperatures hit the 90s), placing them in shade, and keeping them well watered (1” to 2” per week) helps keep them cooler.
Hostas also love a rich, organic, well-drained soil. Should you feel the need to fertilize, a standard 10-10-10 fertilizer should do the trick; just be sure to stop fertilizing six weeks before frost.
Why We Love Them
But what makes these plants so popular? I believe it is their diversity. We have already learned that they will take some sun or shade. They range in size from an entire plant that fits in a teacup, with leaves the size of a thumbnail, to the most mammoth—‘Sum and Substance’, up to five feet high by nine feet wide, with leaves the size of dinner platters; and every size in between!
Colors range from soothing, calming blues and greens, to more vibrant yellows. There is every one of those colors, each with a different colored margin—some margins are wide, some narrow.
The leaf shape also varies, from lance shaped (narrow), ovate (oval), cordate (heart shaped), round or elliptic. The edges can be smooth, slightly rippled to very rippled, or wavy.
The texture can be smooth or corrugated, which is seersucker-like, pebbly in appearance or dimpled. Some plants come straight out of the ground, rise up high and arch outward like a vase. Some fall gently down, looking like a cascade or fountain. Others hug the ground. Still others are cupped, so when a spring rain comes, the leaves fill with water.
The substance of the leaves also affects the overall appearance of the plant. Some leaves are thin, allowing for a more graceful form. Others, said to have “good substance,” are thicker. Currently, the color of the petiole, or stem, is a popular attribute. Various shades of purple to wine to red are emerging, and efforts are being made to push that color up into the leaf itself. What a change that will bring!
Though they are not known for their flowers, some hostas have beautiful ones indeed, most often in some shade of lavender to purple. The species H. plantaginea has fragrant white flowers. The scent is like gardenia or easter lily, and any hosta that has some fragrance has H. plantaginea in its heritage.
Hosta Care
Hostas are long-lived and easy to care for. Problems of note are that deer and slugs like them. Watering early in the day and avoiding deep layers of mulch will decrease the evidence of slugs.
Another important issue currently drawing attention is Hosta Virus X (HVX) (see below).
One final problem that can happen is foliar nematodes, which are microscopic worms that feed on leaf tissue. They are spread by splashing water. The eggs overwinter in the crown of the plant. Symptoms include yellowing between the veins of the leaves in midsummer, turning brown by late summer. The main solution to this problem is to destroy any infected plants, although some sprays and granular pesticides have proven effective.
As a gardener, your role is to be aware of these issues, purchase plants from reputable dealers, and inform others if you see a suspected problem.
No plant is immune from problems, but we all love to garden, nonetheless. Hostas are great plants that offer a tremendous amount of variety and are hardy and beautiful. There are currently well over 3,000 named varieties, cultivars and sports on the market!
Friends School Plant Sale has selected some of the very best for you to enjoy. I hope you pick up a few at the sale—I’m sure you will not be disappointed!
Recognizing and Fighting Virus X
Though symptoms vary considerably from cultivar to cultivar, they most often appear as raised green spots or a blotchy or mottled appearance on the foliage. In the early stages of infection, only a few spots may be evident, but these inevitably increase in number and size.
There is no known cure. Destroy any infected material. Also, destroy any suspicious material. Sometimes only some leaves on a plant show infection, but the entire plant must be destroyed.
As painful as this is, it is better to get the offending plant out of your garden, than to risk spreading the disease.
The virus is believed to be most easily transferred through cutting tools such as pruning shears or knives. Always clean tools between plants.
The American Hosta Society is funding a research project headed by Dr. Benham E. Lockhart of the University of Minnesota. The project is designed to provide empirical data useful for us as hosta gardeners. This study is intended to clarify methods of transmission and understand the dynamics of HVX spread. It will also investigate the length of time the virus remains infectious on tools, hands, and so on.
The hosta community throughout the world is aware of the disease and is actively partnering to get it under control. Through research projects like this, and continued cooperation between growers and retailers, we are confident we will succeed.