If your hostas stop growing, chances are, they will display a variety of other abnormalities as well. Stunted growth is typically a result of an underlying problem like disease. Regularly examining your plants for discoloration and other visual symptoms is your best bet for preventing any permanent growth damage and the potential need for removal.
Stunted growth, caused by a variety of issues, is typically avoidable through optimal care. Vigorous plants have a greater capacity to elude and recover from problems that lead to injury. Grow hostas in areas that provide full sunlight in the morning and shaded conditions during the afternoon, when possible. Hostas simply will not tolerate extreme shade or all day sunlight. Cultivate hostas in moist, well-drained, slightly acid loam soil high in organic content. Avoid dry, drought like conditions as these can lead to stunted growth. Irrigate with approximately 1 1/2 inches of water weekly.
If your hosta plants are not growing, you are likely dealing with a pest or disease problem. Examine your plants for other signs of disturbance like chewed areas. Meadow mice, also referred to as voles, are common pests of hostas. Meadow mice feed both on the base and roots of hosta plants. Voles are approximately 5 to 8 inches in length, covered in gray-brown to black-brown fur. Expect to see them near your plants any time of day as they are active both when the sun is up and down. Another problem of hosta plants is disease. Viruses like hosta virus X can lead to growth problems as well as the development of odd patterns, tiny spots and leaf distortion.
Voles are not only a problem on hosta plants, but they can climb trees and feed beneath the soil line on a variety of other plants like turnips and lilies. A vole problem will likely not remain isolated to hostas alone and can lead to widespread damage within your garden. In addition to growth problems, vole damage may result in plant death.
Viruses can result in minor cosmetic damage on hostas to severe injury. Unfortunately, control is tricky since there are no tools to cure viral diseases. In addition to stunted growth, your plant will likely remain in a state of decline.
Keep voles away from your hosta plants by first keeping your gardening space free of weeds as they attract pests like voles. Install wire fencing around your garden to keep the voles off of your desired plants. Make the fence a minimum of 12 inches high and approximately 10 inches below ground to keep the voles from digging into your space.
Viral diseases are difficult to deal with since there are no effective chemical controls. However, you have some management options when it comes to keeping your garden free of virus-ridden hostas. Only plant healthy hostas from reliable sources. Keep equipment sanitized to prevent virus transmission from one plant to the next. For already infected plants, your bet option is to remove and destroy the hosta, according to the University of Illinois Extension.