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What is rust? This fungus affects a wide range of woody and herbaceous plants. Even though it rarely kills plants, it reduces a plant's health, vigor, and flower production.

How to Identify Rust

  • Look for yellow or white spots forming on the upper leaves of a plant.
  • Orange or yellow spots or streaks appear on the undersides of the leaves.
  • Within these spots that form are spores.
  • Usually leaf distortion and defoliation occur.

How to Control Rust

  • Remove all infected parts and destroy them. For bramble fruits, remove and destroy all the infected plants and replant the area with resistant varieties.
  • Clean away all debris in between plants to prevent rust from spreading.
  • Avoid splashing water onto the leaves, as this can help spread rust.


  • Dust your plants with sulfur early in the season to prevent infection or to keep mild infections from spreading.
  • Space your plants properly to encourage good air circulation.
  • Avoid wetting the leaves when watering plants.
  • There are many effective rust fungicides you can try. Ask your local nursery for which products you should use.


I have several hydrangeas

By Deb Jordan

I have several hydrangeas that were planted by the previous home owners. I live in NC. In late August when moved in, all the blooms were dead and dried and most of the leaves had rust spots. It is now November and the plants are developing nice green new growth at the end of the branches. However, almost all of the old leaves have many rust spots and are pale green. I would love to prune the plants way back to remove all the rust and start new healthy growth. Can I do this? When? How short? Will they bloom next year? Is there anything I should do to kill and avoid further rust? Thank you so much for your advice.

Hi Deb, Please go to the page

By Almanac Staff

Hi Deb,

Please go to the page below and scroll down to see some pictures of "rust" on hydragea leaves and some advice on how to take care of it.

Depending on what type of hydrangea you have you can prune in the fall or in the spring. If you don't know the variety and prune now you may not get any blooms next summer.

For pruning advice got to our hydrangea page at

Just planted a Hortensia

By Carole Clark

Just planted a Hortensia hydrangea early this summer. Had only 1 bloom on it, but a few of the leaves started to turn brown on the edges. Now all the leaves are doing this, brown w/tiny white spots. What can I do?

Hi, Carole: This could be any

By Almanac Staff

Hi, Carole: This could be any number of things, or even a combination, but it sounds like powdery mildew is a good place to start. Go to "Gardening" above and click on "Pests and Diseases Library." Find "Powdery Mildew" and follow the instructions there. While you're there, check out other diseases and see if any of the photos more closely resemble what is happening to your plant. In general, though, clean off or remove the bad leaves, make sure your plant has good air circulation, don't overwater (although brown edges without the white spots might mean underwatering), and put down a thin layer of mulch below the plant to cover up any residual nasties that may be lying in the soil and potentially become harmfully airborne again.

Last year was given 5 plants

By Grannyxfive

Last year was given 5 plants from 5 different sources. I noticed spots so I removed all the leaves. They are filling out nicely now again. However 3 days ago noticed every leaf on both stalks on 1 plant have all drooped including new growth. One other plant has some drooping leaves as well but the rest are fine. I water in the evenings & have sprayed the plants with soap/H20 solution 2 times as I'm seeing spots again. Suggestions? Tampa, FL

  Rust thrives in wet

By Almanac Staff


Rust thrives in wet conditions, so do not overwater your plants. Also, make sure that you have good air circulation around the plants.

We suggest that you spray the plants with organic neem oil, found in most garden centers.

I have a plumeria plant and I

By Ron Keller

I have a plumeria plant and I live in Orlando, Fl. I am loosing my leaves to rust. In the article above, It states that I should remove the leaves and destroy them. I am new to caring for plants so forgive my dumb questions. Do I just strip the plant of all it's leaves? It's a small plant, it has about 15 leaves on it. Anytime I pull a leaf off, it oozes a milky white that normal? Will stripping off all the leaves kill the plant or will it grow new ones fast? My apologies for my ignorance. Thanks for the help,


Hi Ron, Carefully remove the

By Almanac Staff

Hi Ron,

Carefully remove the infected leaves and throw them out with the trash. Instead of pulling the leaves off use clippers or scissors. Rust is common in the fall months. Normally the plant will go dormant and  will drop all its leaves for several weeks in the winter. When new leaves emerge in the spring the rust is usually gone.


What about on your lawn? I

By Roberto

What about on your lawn? I have rust on my lawn does anybody have any ideas.

Hi, Roberto, One of the main

By Almanac Staff

Hi, Roberto, One of the main reasons that rust develops is a low amount of nitrogen in the soil. Fertilize with a good organic fertilizer high in nitrogen to strengthen the lawn. Mowing the grass a little shorter and removing the clippings, plus watering in the morning will also help. --TOFA

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