Why Do My Plantain Lilies (Hostas) Look Unhealthy?

Do the leaves have large, ragged holes in them?

Are the leaves small, light brown, papery, scorched or bleached?

Have the stems blackened at the base, leaves are yellow and wilted, plant collapses?

Do the leaves have moist or brown spots on them?

Are the flowers of your plantain lily covered with gray mold?

Do the leaf edges have semicircle eating damages?

Large, ragged holes in the leaves are caused by slugs and snails. Slugs and snails feed on the plant leaves usually at night. To control slugs and snails use diatomaceous earth around your plants. You can also handpick them during the night or use shallow dishes filled with beer as a trap.

These symptoms can indicate a lack of water or too much sun. An easy way to ruin hostas is to let them dry out, even for a little while. Even if they continue to grow, plants will be stunted. Sunburned edges or spots reduce hostas ornamental value significantly and are best avoided through proper selection of planting sites.

Hostas are susceptible to fungal and bacterial Crown rot disease when grown in poorly drained soil. Crown injury and excess moisture during dormancy also increase the chances of infection. Choose well-drained sites. Add organic matter to improve soil drainage. Keep winter mulch away from crowns. Remove and discard infected plants and the surrounding soil.

Your hostas might be suffering from Anthracnose or some other fungal leaf spot. Spots may enlarge rapidly, especially in wet weather. Destroy infected leaves or plants. Spray plants with sulfur to prevent the disease from spreading, especially if the weather is wet. Prevent problems by thinning plants to provide good air circulation.

Likely cause for these symptoms is the fungal disease - Botrytis blight. Other symptoms include brown spots that may appear on leaves and petals that may turn black. You can only prevent Botrytis blight disease by planting in areas with good air circulation. Water plants so leaves can dry up before sunset. Infected plants should be removed. Spray weekly with a copper fungicide until the disease is under control.

Black Vine Weevil (Otiorhynchus sp.) is a large beetle whose adults and larvae feed on hostas. This beetle is not particularly choosy about its dietary plan. Beetles and larvas are very stubborn and occur especially in dry and raw humus-rich soils. Place flowerpots filled with wood wool near falling plants. The beetles will accumulate in the pot and then they can be collected and destroyed. The larvas can be fought most effectively with parasitic nematodes.

If the whole plants have been eaten, most likely culprits are animals like rabbits or deers. Deer may leave only stalks where beautiful hosta foliage once was while rabbits usually prefer nibbling on the young shoots.