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Rust - Plant Disease Library - Saferbrand


It’s not the same rust that you see on metal. There are over 5000 known species of rust found on plants. They are fungi that travel through the air to settle on a host plant.


Some of the common symptoms of rust include defoliation, stunted growth or branch dieback.





So... What is Rust?

It’s not the same rust that you see on metal. There are over 5000 known species of rust found on plants. They are fungi that travel through the air to settle on a host plant.






Rust is typically brownish-yellow to bright orange spots that form on leaves. The spots are filled with a powdery substance.  This substance contains the spores that will spread to other plants if not treated.





Symptoms of Rust

Plants that have rust growth will not directly die from this type of fungi, but it can contribute the decline of the plant.


Some of the common symptoms include defoliation, stunted growth or branch dieback. Leaving your plant exposed to rust will surely infect other plants since rust is easily spread through the air.





Plants That Are Susceptible to Rust

There are over 7800 known species of rust that affect plants and different species affect different types of plants. As a general rule, most plants can be affected by rust and the best course of action is at first sight, treat your plant with a product such as Safer® Brand Garden Fungicide so you can eliminate the rust and prevent widespread dispersion.





Natural & Organic Controls


Sulfur or Copper fungicides, such as Safer® Brand Garden Fungicide, will help prevent rust from getting worse and help you control future outbreaks.


Garden Fungicide to help prevent rust


Sulfur or Copper fungicides change the pH balance of the plant, creating an environment where Rust and other fungal blights cannot thrive.


Generally, most organic solutions help with disease control because when the soil is healthy, (and not full of harmful chemicals) there is a never-ending battle between the good microbes and the pathogens and the microbes often win.


Carefully read and follow all instructions on the product packaging for safe and effective results. It is recommended with any pesticide to test plants for sensitivity to the product. Spray a small section of the plant in an inconspicuous area and wait 24 hours before full coverage.


IMPORTANT:  Do not use products containing Neem Oil within 14 days of applying these fungicides. The mix of both products can greatly increase risk of phototoxicity (burning) to your plant.



Spray the fungicide when you notice the symptoms of Rust and then again as needed in 7-10 day increments. As a general rule, much like watering, do not use these products in the peak of the day or when temperatures exceed 90 degrees F to avoid wilting or browning of the leaves.


Fungicides can also be used as a preventative measure against fungal infections because the fungicide changes the pH of the plant and creates an environment that is not conducive to disease growth. Treatment once a month is recommended but in heavy rain seasons, treat every 7-10 days for best results.


Why Chose a Natural Solution?

Using organic solutions in your garden is an important step in controlling diseases such as rust.


Some organic ingredients like the patented seaweed extract in our Safer® Brand fungicide products actively increase a plant’s resistance to disease because it is a root growth stimulator, controlling many types of plant pathogens through increased biological activity. This is what many gardening experts refer to when they talk about the natural defenses of a plant and it is similar to antibodies in a human immune system.


Treating an infected plant with an organic fungicide is treating a symptom of the bigger problem. Keeping the living organism in the soil protected by using organic products is not only good for the global environment; it also helps protect your plants from further outbreaks and other issues like insects.





Limit Rust Outbreaks With These Garden Tips


Make sure the soil around your plant is properly drained.  Without proper drainage, your planting area can be a ripe breeding ground for disease organisms.




Adding organic materials through composting will generate beneficial microorganism activity which fights away disease and other garden problems.



Keep leaves as dry as possible. Water plants at the base instead of the leaves. Rust thrives in wet conditions.


Remove all diseased leaves or branches throughout the season and once again before winter. Remove all diseased leaves and canes from the plant and surrounding areas.


Images courtesy of Oklahoma State University and Forestry.
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Safer®Brand brings you a variety of effective plant disease control products that are gentler on the environment! Most of them proudly display the OMRI Listed® organic seal and comply for use in organic gardening!


organic gardening products with the OMRI listed seal