Hostas are staples in shade gardens worldwide. Known for their versatility, durability, and tremendous variety, these hardy perennials bring color and interest to landscapes with minimal effort. Both beginners and experienced gardeners can appreciate these plants.
Description | Care & Growing Conditions | Use in the Garden | Species & Cultivars | Propagation | Potential Problems | More Information
Description
Hostas are highly collectible and offer endless choices for the shade garden. In some areas, they are referred to as plantain lily or funkia, but today, nearly all gardeners know them by their genus name, Hosta. Plants are clump-forming perennials creating a mound of leaves, with some cultivars being extremely compact and others more open, bushy, and occasionally upright. Hostas are known for their colorful, large, heart-shaped leaves ranging in size from less than an inch to 12+ inches, depending on cultivar. Leaves can have a wavy texture, smooth margins, or even be twisted. Leaf texture is often shiny and smooth, but can be puckered or covered in a powdery bloom (called pruinose).
While they are grown primarily for their leaves, attractive racemes of lavender, purple, or white flowers rise above the foliage in June and July. Gardeners are sometimes conflicted by hosta flowers. They can be beautiful, occasionally fragrant, and even attract pollinators and hummingbirds. However, they can sometimes distract from the foliage, which for many gardeners is the "main event." If not desired, flowers can simply be pruned out at the base when they appear without causing any damage to the plant.
Sizes
The American Hosta Society classifies hostas by leaf size in square inches (leaf length×leaf width).
- Miniature Leaved <6 square inches
- Small Leaved 6 to <30 square inches
- Medium Leaved 30 to <64 square inches
- Large Leaved 64 to < 120 square inches
- Giant Leaved 120 or greater square inches
Colors
Hostas are also classified by leaf color and variegation. All colors are available in a wide variety of leaf sizes, shapes, and textures. Leaves can be green, blue, yellow, or chartreuse, and many cultivars feature variegated margins in yellow, white, chartreuse, green, blue, and many shades in between. Leaves can also be streaked or mottled and some cultivars will have contrasting petioles (leaf stalks) in reds or purples.
Care & Growing Conditions
All hostas grow best in full to part shade, although sun tolerance can vary by leaf color. Blue hostas generally require heavy shade to retain their blue color and prevent fading. Green varieties thrive in partial to full shade but sometimes tolerate full sun if provided adequate moisture. Most of the yellow and gold-leafed hosta varieties develop their best leaf color in partial sun (approximately 4 to 6 hours). In partial to heavy shade, leaf color is often yellow-green. Varieties with large amounts of variegation should be planted in shade to prevent leaves from burning.
Plants prefer moist well well-drained soils, but tolerate dry conditions once established. While they may tolerate dry conditions, plants are happiest when not allowed to get overly dry. Irrigate when soil conditions are dry, and remember that gardens under trees are likely to dry out sooner because of root competition from the trees. Provide a layer of organic mulch, such as shredded bark, leaf mold, or shredded leaves to reduce weeds and conserve soil moisture.
Most Iowa soils provide adequate fertility for hostas, especially if organic matter is layered on as mulch on a regular basis. Plants can be fertilized using a general, all-purpose fertilizer in spring as leaves emerge. Apply at the rate recommended on the packaging.
Flowers appear in spring and summer. Spent blooms should be removed to improve appearance and prevent them from going to seed. For the gardener who does not like flowers, they can be removed before bloom with no adverse effects on the overall health of the plant.
Use in the Garden
Hostas are the dominant plant in the typical Midwestern shade garden. The variety in size, color, and leaf pattern makes even hosta-only plantings interesting. The large coarse foliage pairs nicely with the fine foliage of other shade perennials like astilbe, goat's beard, and ferns.
Because their large leaves emerge a bit later in the spring, they are great companions for spring-blooming bulbs, like tulips, daffodils, hyacinth, snowdrops, squill, grape hyacinth, ornamental onions, and others. The bulbs emerge and flower, and the leaves of the hosta expand later in spring to help mask the dying foliage. Hostas also pair nicely with many woodland natives like columbine, Dutchman's breeches, Virginia bluebells, bloodroot, and woodland phlox, as hostas allow these natives to shine in spring, and then their large leaves can fill in the bare spots left behind by the ephemeral species.
Because they are so popular and tough, they are sometimes planted in areas where they cannot thrive. This includes full sun and overly dry locations. Often, they can tolerate these conditions when provided supplemental irrigation, but commonly leaves develop brown edges, bleached areas, and an overall ragged appearance later in the growing season.
Species & Cultivars
Hostas are highly collectible and offer endless choices for the shade garden. There are hundreds of different cultivars in different colors, sizes, shapes, and textures, providing a wide variety of plants to choose from.
Leaves can be green, blue, yellow, or chartreuse, and many cultivars feature variegated margins in yellow, white, chartreuse, green, blue, and many shades in between. Leaves can also be streaked or mottled, and some cultivars will have contrasting petioles (leaf stalks) in reds or purples. Depending on cultivar, sizes range from a few inches tall to over 3 feet. Leaves can be smooth, puckered, wavy, or covered in a dusty powder (pruinose).
All this diversity makes for a lot of plants to collect. Learn more about some of the species and cultivars to look for the next time you are in the garden center in this article: Hosta Types and Cultivars for Iowa.
Propagation
Division
For home gardeners, propagation by division is best. By dividing plants, you are assured that the leaf patterns and colors are preserved in the propagules. Dig up the entire clump as soon as the leaves begin to emerge. (The emerging leaves are bullet-shaped and are often referred to as “points” or “noses.”) Carefully divide the clump into sections with a sharp knife or spade. Each section should have at least 2 or 3 points (leaves) and a good portion of the crown and root system. Replant immediately.
While spring is the best time to divide hostas, plants can be divided anytime from spring to late summer. Hostas divided in late summer should be mulched with several inches of straw, pine needles, or other materials in late fall. Mulching helps prevent repeated freezing and thawing of the soil during the winter months that could heave late summer divisions up out of the soil and damage or destroy them.
These strongly clump-forming perennials grow larger each year, and eventually, the center will begin to die out. When dividing, be sure to remove and discard the dead center of the plant. Frequent division (every 5 to 7 years, or more!) helps keep plants healthy and an attractive size. Plus, it gives you plants to share and grow your garden!
Learn more in this article: How to Divide and Transplant Perennials.
Seed
If you want to dig your toe into developing new cultivars, plants must be crossed and grown from seed. Collect the seed as soon as it ripens from the pods that develop on the flower stalks. Store the seed and sow outdoors 6 to 8 weeks before the last frost in spring. Seeds germinate in 15 to 90 days. You can get a head start on growing plants by sowing the seed immediately after collecting in pots indoors. Plants will reach flowering size in three years.
Tissue Culture
While not done by the home gardener, nurseries and greenhouses often propagate hostas using tissue culture. This method of propagation requires special equipment and sterile environments and produces genetic clones from small amounts of plant material. This is a far more efficient way to get clones than division, which requires years for plants to get large enough to divide.
Potential Problems
Hostas are popular shade garden perennials. Their attractive foliage, endless diversity of shape and size, tolerance of shady areas, minimal maintenance needs, and relatively few pest and disease problems are what make them so popular. While they are tough, easy-to-grow plants, they are not free of problems. Several diseases and pests can reduce plant vigor and aesthetic value.
Learn more in this article: Pests and Diseases of Hosta.
More Information
- Growing Hostas (PDF)
- Perennials for Shady Areas
- Perennials for Shady Areas (PDF)
- Perennials for Shade (PDF)
- Groundcovers for Shade
Photo credits: 1: Aaron Steil; 2: Aaron Steil; 3: Aaron Steil; 4: Aaron Steil; 5: Aaron Steil; 6: Aaron Steil; 7: Aaron Steil; 8: Aaron Steil; 9: Aaron Steil; 10: Aaron Steil; 11: Laura Jesse