How can I help my hosta plants that have black spots on the leaves?

Miriam Holmes
by Miriam Holmes

My hostas are Beautiful! But black spots are coming up on the leaves. I need a home remedy πŸ™πŸΎ

  5 answers
  • Lynn Sorrell Lynn Sorrell on Jul 18, 2019

    fungal disease --- https://extension.psu.edu/hosta-diseases Fungal diseases in particular are a huge problem for mid-summer gardens where hot and humid weather is common. Fungal diseases love the constant moist air, little rain or sun, and cool nights of summer. Annoyingly, once one plant becomes infected, you’re likely to see the problem spread if you don’t take action.

    If you know your garden is prone to certain garden diseases, like powdery mildew or black spot, or if you suspect a fungal disease is attacking your favorite plants, there are a number of products available, both conventional and organic that you can use for prevention. I like copper fungicides like Espoma Earth-Tone or Bonide Liquid Copper Fungicide. Some organic gardeners also report good luck with Neem Oil (which is both an insecticide and fungicide), or Serenade Garden Disease Control.

    Before you fork over your life savings for the latest fungicides or organic microbial treatments, be sure you are doing the most to first prevent moldy conditions in your garden:

    – Use a layer of mulch to keep your your ground covered and your leaves away from the soil where most fungal diseases hang out.

    – Thin out, divide, or prune back crowded plants so that they get good air flow and a little bit of sunlight.

    – Water and feed your plants to keep them healthy. Plants that are stressed for water or nutrients are more susceptible to common garden diseases.

    – Try to water deeply at the base of your plants. Avoid watering in late afternoon or evenings!

    – Disinfect your pruners with a bleach or a vinegar formula so that you don’t spread microbes from diseased plants to healthy plants.

    – Don’t compost diseased plant materials that you have cut back or cleared away. Most home compost piles won’t be hot enough to kill off infectious organisms. Bag that stuff and send it to the town dump or town composting operation. If you have nowhere to send the diseased plants, some people recommend burying the diseased plant materials in a part of your yard away from vegetable or flower gardens.

    – Plant resistant varieties of flowers and vegetables. There are many newer introductions of flowering plants and vegetable seeds that have been bred to resist common garden diseases. Ask your local garden center about these varieties.

  • Miriam Holmes Miriam Holmes on Jul 18, 2019

    Thank You πŸ™πŸΎ πŸ€—


  • Dolores Gill Dolores Gill on Jul 19, 2019

    neem oil

  • Cindy Cindy on Jul 20, 2019

    Hi Mirinam. It sounds like your Hostas have fungus. I recommend using Neem Oil. You can buy it on Amazon for approx. $20.