Identifying and Treating Rust Fungus

Rust fungus sunflowerRust fungus appears as a brown rusty coating or spotting on plant leaves and stems, and the spores will be orange-brown raised bumps on the undersides of the plant leaves. If you check your container plants often, you will be able to spot rust early on and treat it before it becomes too serious in your balcony garden.


Rust is a fungus, and usually each species of fungus attacks one single host species. This means that if you find rust spots on one of your container plants, it shouldn’t move to the other types of plants in your apartment garden.

Prevention. Taking good care of your container plants will cut down the likeliness of rust (and other pests and diseases) appearing in your balcony garden. Make sure that plants have adequate air circulation (they’re not too tightly packed with other plants) and that you do not overwater. Rust may still affect your container plants, so always keep an eye out for garden pests and diseases while caring for your plants.

Treatment. If you do find rust, first remove the affected plant leaves. Never compost these leaves; throw them away immediately. Gardeners are encouraged to burn infected plant parts, but apartment gardeners will most likely not be able to do this. Wrap them up tightly in a plastic bag and throw them away.

Anti-fungal sprays are available at your local garden shop. You will most likely need to spray your plants at a time when it is not likely to rain. Continue removing affected plant leaves and using a spray until the rust is gone.

Fungus can live in the air and in potting soil, so the problem may come back. Just be vigilant and know the signs of disease or garden pests. The sooner you treat the problem, the easier it will be to handle. If rust gets a hold of your the plants in your container garden, it can affect the plant’s growth, and production of flowers and fruits.

11 Common Plants Affected by Rust

  1. Beans
  2. Sunflowers
  3. Chrysanthemum flowers
  4. Fuchsia
  5. Garlic
  6. Leeks
  7. Onion
  8. Pelargonium flowers
  9. Roses
  10. Hollyhock flowers
  11. Snapdragon flowers

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