Garden Variety: Some shady companions — hostas and coral bells

Check out the selection of shade-tolerant plants at about any garden center in the U.S., and you are sure to find hostas and coral bells. The popularity of hostas in the U.S. goes back to the 1800s, while coral bells (also known by their botanical name heuchera) only gained popularity after major hybridization in the 1990s. Within these two plant groups, there are thousands of varieties from which to choose with a broad range of shapes, sizes, colors and textures.

Most hostas and heucheras are planted for their attractive foliage rather than their flowers. In Kansas, these plants grow best with a mix of sun and shade, although some varieties can tolerate full sun or deep shade. (Most will scorch in hot dry summers even if labeled full sun, though). All hostas and coral bells grow best in well-drained, fertile soil without heavy competition from tree roots.

Old-fashioned hostas were mostly a cluster of green or green and white variegated leaves with wide stems. Newer varieties come in various shades of green, blue-green, yellow, and everything in between those colors. Variegation also ranges considerably. The smallest hostas are suitable for fairy gardens, while the largest rival many small shrubs.

Read labels when selecting hostas to determine mature size and get a better idea of how the mature plant looks. An example of a small hosta is Blue Mouse Ears, which grows to about 6 inches tall with 2-inch diameter blue-green leaves. One of the largest hosta varieties is Empress Wu, which grows to 4 feet tall by 6 feet wide with thick, wavy, medium-green leaves. Golden Tiara, Sum and Substance, Guacamole, and Elegans are common medium-sized varieties.

Coral bells are typically more tolerant of sun than hostas, but less tolerant of heavy soils. They also produce a cluster of leaves just above the ground, but their leaves are held on delicate stems like tree leaves. The color range for coral bells is various shades of purple, red, orange, yellow, and green. Some varieties also have a distinctive silvery-white variegation.

Coral bells have less variation in size than hostas, with most being 12 to 18 inches tall and wide, with flowers held on long stems slightly above that. The dark variety Palace Purple was one of the first to bring coral bells mainstream, and it is still available but rivaled by the silvery-purple Frost, Chocolate Ruffles, Black Taffeta and others. Paris and Peppermint are green and silvery leaved plants, while Marmalade, Paprika, and Peach Crisp offer a range of orange-y shades.

Another variation of coral bells are referred to as heucherellas. They are crosses between heuchera and plants from another genus, tiarella. The only differences you might notice are an increase in the number of options of color variegation and an increase tolerance to shade.

Plant hostas and coral bells in masses to get the greatest effect (with the exception of the very large hostas which may be planted individually as a focal point). Groups of odd numbers are most pleasing to the eye, so select 3, 5, 7, etc. of a variety. Try planting a group of green and white variegated hostas next to a group of deep green ones to really make the variegation pop, or add in other flower species to bring out the yellows and blues.

The popularity and availability of varieties of both types of plants changes often, so the best bet is to go shopping and pick out plants that appeal to you. Local garden centers typically have the best idea of what varieties are the most reliable for this area. Collectors may want to research specific varieties for their collections.

Hostas and coral bells have few pest problems. Avoid planting too deep, overwatering, or over fertilizing. Provide supplemental water when/if plants wilt over extended dry periods.

— Jennifer Smith is a former horticulture extension agent for K-State Research and Extension and horticulturist for Lawrence Parks and Recreation. She is the host of “The Garden Show.”