A mainstay of any shade garden in the Midwest, Hostas are grown partly for their flowers but mainly fabulous foliage. To keep that foliage looking great, watch out for these problems.

Fortunately, you are far less likely to run into Hosta Virus X (HVX) today than a decade ago, thanks to Hosta grower’s diligence in eradicating it from commercial trade. No controls exist for HVX, so the destruction of the infected plant is our only recourse.

Are large, irregular tan or brown spots surrounded by dark borders showing up on your Hosta leaves? A fungal disease called Anthracnose is to blame. Whatever you can do to keep the leaves dry will help. Forego overhead watering for drip irrigation or pushing the leaves aside to water just the soil at the plant base. Also, planting for good airflow helps.

Is your Hosta completely defoliated with ragged stems left behind? Deer have been snacking in your yard, and it is one of their favorite foods. Fencing them out provides the best protection, but if that isn’t an option, many nasty smelling deterrents exist. Continually rotate the odors and reapply after rain.

Have you noticed part of the plant wilting and can easily be lifted right out of the ground? Or, has the plant disappeared into a nearby tunnel? Voles are at work in your Hosta bed. Being rodents, traps, and poisons that work on mice will also kill voles. If you prefer to discourage them, try mixing some pea gravel into the soil surrounding the plant.

Are there irregular holes in the leaves along leaf edges or between veins? Do you also notice a slime trail on the leaves? You guessed it. Slugs are the culprits. The preferable solution is maintaining a healthy garden environment where toads and frogs can thrive and feast on the slugs. The other choice is trapping them by a variety of methods. Some gardeners use a damp board set out close to the Hosta. During the day, the slugs shelter in the damp under the board where you can collect them for disposal. Others prefer the beer-in-a-bowl sunk in the ground method. The slugs slide into the liquid and drown. Do not use salt. Repeated use of salt will poison your soil and your Hosta.

Finally, weather and humans can damage your plants. Hail and excessive wind are threats. Remove the damaged leaves if they are unsightly. For severe damage, rejuvenate prune by cutting the Hosta down to the ground. It will grow back but probably won’t be as large the following year. People damage comes from walking on the plants or string trimmers getting too close.
 
For information on Hostas or any other plant, call University of Illinois Extension Master Gardeners of Edgar County at 217-465-8585.

SOURCE: Jan Phipps, Master Gardener, Edgar County
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